Dissertations / Theses on the topic 'Metal-cutting tools'
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Darwish, S. M. H. "Adhesive bonding of metal cutting tools." Thesis, University of Birmingham, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.488941.
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The aim of this work is to develop techniques and to optimize the process of bonding of cemented carbide metal cutting inserts. This replaces the common methods of clamping or brazing. The first stage was to-survey and test structural adhesives to select the most promising adhesive for metal cutting applications. This resulted in a choice of toughened epoxy heat cured adhesive. A comparison between bonded and brazed joints, from the damping capacity point of view was made. In this comparison adhesive bonding resulted in, a higher damping capacity when compared with brazing. The bond line thickness proved to be significant in increasing the damping capacity of the bonded joints. A comparison was carried out between the heat flow through bonded and brazed tools, and demonstrated pronounced heat insulation in the bonded tool, which depended mainly both on the thermal conductivity of the adhesive material and the thickness of the bonded layer. The effectiveness of the bond line thickness, from the points of view of thermal conductivity and developed thermal stresses was investigated. This showed that the thinner the bond line the better is the performance of the bonded joint. The effect of coolant on the temperature of the bond line as well as the tool tip was also investigated. Mixing metallic powder with the adhesive material in order to increase the thermal conductivity of bonded tools was investigated. A new apparatus for measuring low thermal conductivity is proposed. Extensive cutting tests were carried out in order to assess the performance of bonded tools with and without coolant, reground tools and bonded tools having copper powder mixed with the adhesive. The assessment of cutting performance when using bonded tools compared with brazed tools showed that not only a better surface finish could be obtained with bonded tools but also far less tool flank wear
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Haron, Che Hassan Che. "Machining of titanium alloys with coated and uncoated carbide tools." Thesis, Coventry University, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.262998.
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Sripathi, Prajwal Swamy Payton Lewis Nathaniel. "Investigation into the effects of tool geometry and metal working fluids on tool forces and tool surfaces during orthogonal tube turning of aluminum 6061 alloy." Auburn, Ala., 2009. http://hdl.handle.net/10415/1963.
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Vagnorius, Žydrunas. "Reliability of metal cutting tools: : Stochastic tool life modelling and optimization of tool replacement time." Doctoral thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for produksjons- og kvalitetsteknikk, 2010. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-11293.
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This PhD thesis is based on six articles and proposes new approaches for modelling of the life of cutting tools and for determining the optimal tool replacement time. These issues are very closely related and play a critical role in machining economics. Replacing a tool too early means wasting of its potential and leads to high costs and reduced productivity. Late replacement poses a risk of wear-out and other types of tool failures, which can damage the component being produced and can cause expensive equipment downtimes. Therefore a lot of work has been done to develop models for predicting the life of a tool and to optimize its replacement time. Probably the best known of them is the Taylor’s tool life equation. Developed in 1906 Taylor’s equation expresses the tool life in terms of the cutting speed. Despite being over a century old, this model is still widely used in practice. However, Taylor’s equation has a few drawbacks. For example, it ignores the effect of other, though less important, process parameters such as the depth of cut and the feed. To walk around this issue several extensions of Taylor’s equation have been proposed and are discussed in this thesis. Nevertheless all these models share another common flaw. They assume that tool life is deterministic, i.e., that given the process parameters the exact time to wear-out can be calculated. Unfortunately, in real machining processes there are a lot of sources of variation that affect the rate of tool wear and influence its life. As a result, deterministic models rarely give accurate estimates and are only valid as approximations. To improve tool life predictions and assist process planners in choosing the optimal replacement time this PhD thesis proposes new methods. The underlying assumption is that tool life is a stochastic quantity and follows a certain probability distribution. With this in mind the reliability function is derived. Based on the physical analysis of machining processes it is assumed that a tool can fail due to the three main causes: (i) wear, (ii) internal defects and (iii) external stresses. Tool wear depends on a number of factors, including the characteristics of the tool itself, such as its material, geometry and coating, properties of the workpiece material, cutting parameters, rigidity of the machine tool and the efficiency of the cooling process. This last factor is particularly important as most of the tool wear mechanisms depend on temperature. Therefore in this PhD thesis a lot of attention is given to high pressure cooling, which is an effective way to reduce the temperature in the cutting zone. Internal defects are micro voids and cracks that develop inside the tool material during its manufacturing process or as a result of inappropriate handling. They act as stress concentrators and lead to shorter than normal tool life. External stresses are severe overloads that cause immediate tool failure regardless of its quality. They are random in nature and may originate from machine operator errors, failure of supporting equipment or some other external sources. Considering all three failure modes total tool reliability function is found. It is assumed that in a given batch a certain percentage of tools are “bad”, i.e., they contain internal defects, while the rest are “good”. The life of the normal tools is modelled by a two-parameter Weibull distribution. Failures due to internal defects are also accounted for by the Weibull distribution, but with different parameters. Then the life of a tool chosen at random is predicted by the mixture model. In addition, tools of both types can fail due to external stresses, the occurrence of which is model by a homogeneous Poisson process. The derived tool reliability function is used to determine the replacement time. Two models are proposed for this purpose. The first one is called the minimum acceptable reliability approach. The idea is to select such a replacement period that the reliability of the tool during it would not fall below a certain minimum level. We show that, when the reliability function is known, this can be done by using a simple graphical procedure. The second model is based on the age replacement policy, which attempts to balance the costs of preventive and failure provoked tool changes. To solve this optimization problem the total time on test (TTT) transform of the reliability function is introduced, and a method for estimating it form the experimental data is proposed. Then, as in case of the first model, the replacement time is found by employing a simple graphical procedure. For the above approach to be used in practice the expected costs of preventive and failure provoked replacements need to be known. It is shown that the former one can be determined by applying traditional formulas found in machining economics handbooks. The penalty cost, on the other hand, is not so well defined, and no good estimation models are available. Therefore, a new, probability tree-based approach is developed in this thesis. The relevance and the applicability of the proposed models is tested in a few experimental and case studies described in the appended articles. In Article 1 reliability of machining systems as a whole is investigated, and the stochastic nature of the processes involved is clearly shown. In Article 2 it is demonstrated that a two-parameter Weibull distribution can be used to model the tool life, and a simple replacement model based on the reliability function is proposed. In Article 3 a more generic tool life model is developed, but a two-parameter Weibull distribution is still found to be a good approximation. The replacement time is than found by employing an optimization procedure based on the age replacement policy. In Article 4 an approach for estimating the penalty cost, which is a key input to the age replacement model, is developed. Finally in Articles 5 and 6 it is shown that high pressure cooling can help to extend the tool life and possibly to reduce its variation, which is the main reason why probabilistic models are needed. Based on this experimental work and case studies the thesis concludes that stochastic approaches for tool life modelling and for determination of replacement time are relevant and applicable in practice. Therefore further work needs to be done to extend the use of these methods beyond the set-ups and conditions tested throughout the research described in this PhD thesis.
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Qian, Zhen-Qing. "An investigation into entry and exit failure of metal cutting tools." Thesis, University of Newcastle Upon Tyne, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.241345.
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Park, Young-Bin. "Sheet metal forming using rapid prototyped tooling." Diss., Georgia Institute of Technology, 2003. http://hdl.handle.net/1853/18361.
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Aiso, Toshiharu. "Workpiece steels protecting cutting tools from wear : A study of the effects of alloying elements on material transfer and coating damage mechanisms." Doctoral thesis, Uppsala universitet, Tillämpad materialvetenskap, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-306190.
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The vision of this thesis is to improve the machinability of workpiece steels. Workpiece material frequently transfers to the cutting tools during machining, and the transfer layers then forming on the tools may give both good and bad effects on machining performance and tool life. The objective of this work is to understand the effects of alloying element additions to workpiece steels on material transfer and the roles of the formed transfer layers on friction characteristics and wear of tools. To isolate and study the influence of the individual alloying elements, model steels are specifically designed. These steels include one reference with C as the only alloying element and others alloyed also with single additions or combined additions of 1 mass% Si, Mn, Cr and Al. The experiments are performed using both a sliding test, simulating the material transfer in milling, and a turning test. In a sliding contact, the mode of transfer is strongly dependent on the normal load and sliding speed. Material transfer initiates extremely fast, in less than 0.025 s, and characteristic transfer layers develop during the first few seconds. The different steel compositions result in the formation of different types of oxides in the transfer layers. At the workpiece/tool interface where the conditions involve high temperature, high pressure and low oxygen supply, easily oxidized alloying elements in the steel are preferentially transferred, enriched and form a stable oxide on the tool surface. The degree of enrichment of the alloying elements in the oxides is strongly related to their tendencies to become oxidized. The difference in melting temperature of the oxides, and thus the tendency to soften during sliding, explains the difference in the resulting friction coefficient. The widest differences in friction coefficients are found between the Si and Al additions. A Si containing oxide shows the lowest friction and an Al containing oxide the highest. The damage mechanism of coated tools is chiefly influenced by the form and shear strength of the transferred material. Absence of transfer layer or non-continuous transferred material leads to continuous wear of the coating. Contrastingly, continuous transfer layers protect it from wear. However, transfer layers with very high shear strength result in high friction heat and a large amount of steel transfer. This leads to rapid coating cracking or adhesive wear.
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Graver, Thomas William. "Determination of cutting-tool inventory levels in a flexible manufacturing system." Thesis, Georgia Institute of Technology, 1987. http://hdl.handle.net/1853/30775.
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Garzon, Inti Elias. "Optimisation for product and process improvement : investigation of Taguchi tools and genetic algorithms." Thesis, University of Newcastle Upon Tyne, 2000. http://hdl.handle.net/10443/471.
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Despite criticisms of its methodology, the Taguchi philosophy for quality improvement is generally applauded. Though originally intended to primarily achieve its results "off line", during the product design phase and before manufacturing, it has frequently also been deployed to solve problems "on line". Taguchi identifies the crucial design phases as "system design" and "parameter design", and his statistically-based tools are directed at the latter. The general objective of this investigation is to study two contrasting approaches to product and process optimisation, ie Genetic Algorithms, which may be appropriate to both "system design" and "parameter design" phases, with Taguchi and related statistical tools which may be appropriate to the "parameter design" phase. The literature review concentrates on the up and downsides of Taguchi Methods, focusing on the philosophy and methodologies. Its statistical content, particularly related to the use of Signal-To-Noise ratios and saturated fractional factorial designs, have widely reported deficiencies. In order to evaluate and, if necessary, overcome these deficiencies, a combination of Taguchi and non- Taguchi tools are brought into an experimentation strategy to determine robust methodologies that contribute to enhanced product performance. The approach is motivated from a design for quality standpoint and is directed principally at improving performance. The approach is illustrated using three case studies in surface finish from metal cutting and simulation systems optimisation. These case studies involve a variety of experiments different in nature, from real physical experiments to computer-based ones, and tackling a wide range of different problems such as: surface finish in milling and turning machining (metal cutting), optimum travel time and traffic junction control (transport traffic simulator) and out-of-balanceforce problem (optimisation of simple Genetic Algorithms). The study of Taguchi tools is an extension of previous work by Taher (1995). Some of his investigations are extended, principally the reliability of Taguchi saturated fractional factorial arrays, the need for factor/level analysis, criticisms of the Taguchi Signal-to-Noise ratios and the use of sequential experimentation. In addition to these, attention is focussed on the use of repetitions within the Taguchi methodology, the use of transformations or Generalised linear Models and the possibility of using robust statistics. The adoption of a sequential experimentation approach leads to a successful use of predefined Taguchi arrays influenced by user knowledge of confounding and interaction effects on main factors. From a global viewpoint, Factor/Level analysis is highly recommended. It is also determined that the reliability of results is highly affected by the use of Signal-to-Noise ratios, and alternative dispersion control tools are strongly advised. Taguchi's robust design methodologies are of value but require integration with other design and quality assurance methodologies, such as Concurrent Engineering and Quality Function Deployment. The optimisation of a simple Genetic Algorithm (for the out-of-balanceforce problem) is used as one test case for the investigation of Taguchi tools. However, this investigation is itself of interest for the general use of genetic algorithms as it addresses issues such as appropriate population size and choices for crossover and mutation modes and probabilities. Many previous investigations of these have only been of the "one factor at a time" type.
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Medaska, Michael Kenneth. "The measurement of temperatures and forces in a turning operation with cutting fluid." Thesis, Georgia Institute of Technology, 1998. http://hdl.handle.net/1853/15983.
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Becze, Charles Edward Elbestawi M. A. "A thermo-mechanical force model for machining hardened steel /." *McMaster only, 2002.
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Choy, Hang-shan, and 蔡恆生. "Tool path trajectory analysis and machining strategy for corneringcut." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2003. http://hub.hku.hk/bib/B31244117.
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Кутовий, Микола Павлович, Николай Павлович Кутовой, and Mykola Pavlovych Kutovyi. "Сучасний металорізальний збірний інструмент." Thesis, Видавництво СумДУ, 2007. http://essuir.sumdu.edu.ua/handle/123456789/19262.
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Руденко, Олександр Борисович, Александр Борисович Руденко, Oleksandr Borysovych Rudenko, К. С. Кісиленко, Ю. В. Клименко, І. Л. Якименко, М. В. Лиштван, and І. В. Чубун. "Створення бази електронних видань галузевих каталогів металорізальних верстатів." Thesis, Видавництво СумДУ, 2011. http://essuir.sumdu.edu.ua/handle/123456789/7455.
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Останніми роками на кафедрі технології машинобудування, верстатів та інструментів створено велику кількість електронних копій навчально-довідкової літератури для дисциплін, які викладаються (підручники; довідники; класифікатори; загальномашинобудівні, загальномашинобудівні укрупнені та міжгалузеві укрупнені нормативи часу), що дає можливість більш зручного використання навчально-довідкової літератури студентами (особливо студентами заочної форми навчання, в тому числі в позабазових структурних підрозділах).
Вже давно з'явилося бажання перевести в електронний вигляд галузеві каталоги металорізальних верстатів, що сприяло б полегшенню пошуку студентами необхідної інформації при виконанні курсових (дипломних) проектів (робіт). Метою даної роботи є створення бази електронних видань галузевих каталогів металорізальних верстатів та побудова пошукової системи використання цих каталогів на базі класифікації по коду ОКП.
При цитуванні документа, використовуйте посилання http://essuir.sumdu.edu.ua/handle/123456789/7455
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Stjernstoft, Tero. "Machining of Some Difficult-to-Cut Materials with Rotary Cutting Tools." Doctoral thesis, KTH, Production Engineering, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3693.
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Automobile and aero industries have an increasing interestin materials with improved mechanical properties. However, manyof these new materials are classified as difficult-to-cut withconventional tools. It is obvious that tools, cutting processesand cutting models has to be devel-oped parallel to materialsscience. In this thesis rotary cutting tools are tested as analternative toexpensive diamond or cubic bore nitridetools.
Metal matrix composites mostly consist of a light metalalloy (such as aluminium or titanium) reinforced with hard andabrasive ceramic parti-cles or fibres. On machining, thereinforcement results in a high rate of tool wear. This is themain problem for the machining of MMCs. Many factors affect thelife length of a tool, i.e. matrix alloy, type, size andfraction of the reinforcement, heat treatment, cuttingconditions and tool properties.
In tests, the Al-SiC MMC formed a deformation layer duringmilling, probably affected by lack of cooling. The dominatingfactor for tool life was the cutting speed. Water jet or CO2cooling of turning did not provide dramatic increase in toollife. With PCD, cutting speeds up to 2000 m/min were usedwithout machining problems and BUE formation. Tool flank wearwas abrasive and crater wear created an "orange-peel type" wearsurface. PCD inserts did not show the typical increase in flankwear rate at the end of its lifetime.
The use of self-propelled rotary tools seems to be apromising way to increase tool life. No BUE was formed on therotary tool at high cutting data. The measurements indicatethat the rotary tool creates twice as good surface as PCDtools. The longest tool life was gained with an inclinationangle of 10 degrees. Tool costs per component will beapproximately the same, but rotary cutting tool allows higherfeeds and therefore a higher production rate and thus a lowerproduction cost.
The rotary cutting operation might have a potential toincrease productiv-ity in bar peeling. The lack of BUE withrotary cutting gives hope on higher tool life. The test resultsshow that tool wear was 27% lower with rotary cutting tools.Increase of cutting speed from 22 to 44 m/min did not affectcutting forces. This indicates that the cutting speed canincrease without significant change in tool wear rate.
Issues related to rotary cutting like cutting models,cutting processes, standards, tools and models have beendiscussed. A tool wear model with kinetic energy has beendiscussed.
KEYWORDS:Difficult-to-Cut material, Metal MatrixComposite (MMC), Machining, Machinability, Rotary Cutting Tool,Acoustic Emission
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Joshi, Kunal J. "OPTIMIZATION OF CUTTING CONDITIONS FOR SUSTAINABLE MACHINING OF SINTERED POWDER METAL STEELS USING PCBN AND CARBIDE TOOLS." UKnowledge, 2006. http://uknowledge.uky.edu/gradschool_theses/379.
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Powder metals are becoming a popular choice in the automotive and other manufacturing industries because of their ability to meet wide ranging product functional requirements without compromising the performance of the product. They offer various advantages, including weight reduction, near net-shape processing capability, and their ability to be sintered to achieve desired properties in the end-product. However, in order to satisfy the product design requirements during manufacturing, they need to be machined to the required tolerances. Machining of powder metals is quite different to machining of traditional metals because of their specific properties, including porosity. This thesis work deals with the finish machining of powder metal steels in automotive applications, for increased tool-life/reduced tool-wear. Tool-life is affected by a variety of factors such as tool grade selection, tool coating, cutting conditions and tool geometry including cutting edge geometry. This work involves optimization of cutting conditions for plunge cutting and boring operations of automotive powder metal components using PCBN and carbide tools. The cycle time of the process introduces an additional constraint for the optimization model along with the tool-wear criterion. Optimized cutting conditions are achieved for maximum tool-life.
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Machado, Marcio Alexandre Gonçalves 1974. "Reaproveitamento de bedames intercambiáveis." [s.n.], 2013. http://repositorio.unicamp.br/jspui/handle/REPOSIP/264572.
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Orientador: Amauri HassuiDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica
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Resumo: Sabe-se que atualmente a competitividade das empresas é fator de sobrevivência. Assim, a busca por redução de custo é um constante desafio. Um aspecto dentro dos processos de fabricação que atua diretamente nesse tocante é o desenvolvimento de melhores ferramentas de corte. Este trabalho trata da reafiação de ferramentas de corte denominadas bedame, que possuem custo mais elevado que as demais ferramentas. O material usinado foi o ferro fundido nodular, que possui propriedades mecânicas características e consumir menor energia em sua fusão. Nos processos de usinagem são utilizadas as mesmas ferramentas para os ferros fundidos nodulares e cinzentos, porém o primeiro é um material dúctil, diferente do segundo que é frágil. Isso implica em um comportamento diferente na usinagem, mostrando que cabe neste caso uma melhor adequação das ferramentas de corte. Após a utilização de bedames novos, estes foram reafiados em quatro modelos diferentes. Posteriormente foram testados quatro tipos de revestimento PVD. Na sequência avaliou-se também a influência da velocidade de corte, avanço e concentração do fluido de corte. O critério adotado para a determinação do fim da vida dos bedames foi à qualidade da face usinada. Os ensaios foram feitos em sequência, sendo que o passo seguinte utilizava apenas os melhores resultados do passo anterior. Os resultados indicaram que bedames com ângulo de saída positivo, revestidos com AlTiN, usinando com menores velocidades de corte e avanço e com maior concentração de óleo no fluido de corte, apresentaram vida mais longa. Por outro lado, o mesmo bedame, só que revestido com TiCN e operando nas mesmas condições, apresentou a melhor relação custo benefício dentre os bedames reafiados. Concluiu-se assim que é viável economicamente a reafiação dos bedames
Abstract: It is known nowadays that the companies' competitiveness is a survival factor. So, the search for cost reduction is a constant challenge. One aspect of the manufacturing processes that act directly in this aspect is the development of better cutting tools. This work is about cutting tools to part materials named parting tools that has higher costs than the other cutting tools. The machined material was the nodular cast iron that has specific mechanical characteristics and demands less energy in its melting. In the machining processes it is usually used the same cutting tools to machine nodular and grey cast iron, but the first is ductile different from the second that is fragile. This implies in a different machining behavior, showing that is possible in this case a better adequation of the cutting tools. After using the new parting tools, they were resharpened in four different models. After that were tried four different PVD coatings. In the sequence it was also evaluated the influence of the cutting speed, the feed and cutting fluid concentration. The criteria adopted to determine the end of the parting tool life was the quality of the machined surface. The tests were carried out in sequence in such a way that the next step used just the best results of the former step. The results indicated that parting tool with positive rake angle, coated with AlTiN, operating in lower cutting speeds and feeds and with higher cutting fluid concentration, presented longer tool life. On the other hand, the same parting tool, but coated with TiCN and operating at the same cutting conditions, presented a better cost benefit relation among the resharpened cutting tools. It can be concluded that is economically feasible the parting tools resharpening
Mestrado
Materiais e Processos de Fabricação
Mestre em Engenharia Mecânica
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Xiong, Guangxi. "A study of tool wear measurement by using image processing system : a thesis." Scholarly Commons, 2001. https://scholarlycommons.pacific.edu/uop_etds/858.
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Xiong, Guangxi. "A study of tool wear measurement by using image processing system." Scholarly Commons, 2013. https://scholarlycommons.pacific.edu/uop_etds/858.
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Arroyo, Osorio Jose Manuel. "Investigação sobr o uso da texturização a laser na preparação da superficie a ser recoberta em ferramentas de metal duro para fresamento." [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/264151.
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Orientador: Anselmo Eduardo DinizTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica
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Resumo: A usinagem é um dos processos de fabricação fundamentais da indústria contemporânea sendo o metal duro recoberto o material mais utilizado na fabricação das ferramentas de corte. A manufatura deste tipo de ferramentas inclui o processamento da superfície do substrato, previamente à deposição do recobrimento, com o objetivo de obter uma elevada resistência de aderência na interface substrato-recobrimento. O método mais difundido com este propósito e o jateamento do substrato com micropartículas de alumina que, embora amplamente utilizado e efetivo, gera poluição, risco à saúde do operador, consome muitos recursos de tempo e mão de obra e apresenta dificuldade no controle da rugosidade. Por outro lado a texturização a laser é uma tecnologia de engenharia de superfície baseada num laser pulsado que modifica a superfície do material através de fusão, evaporação, sublimação e subsequente solidificação. Nesta tese foi explorada a efetividade da texturização a laser como método alternativo ao jateamento na preparação pré-recobrimento da superfície do substrato. Este processo não apresenta poluição, permite o processamento seletivo de áreas especificas da ferramenta e, sendo automatizável, potencialmente utiliza menos recursos de tempo e mão de obra. As ferramentas selecionadas para experimentar foram duas classes de metal duro com recobrimento composto de TiCN+Al2O3+TiN depositado pelo processo MT-CVD, e, na preparação pré-recobrimento da superfície dos substratos experimentais foi utilizado um laser CuHBr pulsado. De acordo com a dinâmica do processo laser utilizado, é possível controlar a rugosidade do substrato e produzir uma grande diversidade de topografias e estruturas de superfície através da variação da intensidade e/ou da quantidade de pulsos do laser. Também foi verificado que o processamento com laser produz sempre transformações do WC, presente no substrato do metal duro, em novas fases não estequiométricas com menor teor de C. Por tentativa e erro, foram determinados dois conjuntos de parâmetros laser que produziram a melhor resistência de aderência avaliada através de ensaios de indentação: 02 pulsos, 410 MW·cm-2 e 64 pulsos, 239 MW. cm-2. Em ensaios de corte, tipo fresamento de topo a seco de aço molde P20 com ferramentas toroidais, foi comparado o desempenho de arestas microjateadas (comerciais) contra arestas texturizadas a laser (experimentais) encontrando uma vida média igual para ambos os tipos de arestas. Na análise detalhada dos mecanismos de desgaste foram encontradas em todas as arestas evidências de difusão, attrition, abrasão, deformação, delaminação, trincas e um mecanismo secundário, chamado desgaste por microfusão do material da aresta. Não houve diferenças notáveis entre as arestas comerciais e as experimentais que fossem atribuíveis ao processo de preparação da superfície do substrato para a deposição do recobrimento
Abstract: Machining is one of the fundamental manufacturing processes of contemporary industry and coated cemented carbide is the most used cutting tool material. Manufacturing of this kind of tools includes the substrate surface processing previously to coating deposition in order to achieve high adhesion resistance in the substrate-coating interface. The most spread out method with this intention is the substrate blasting with alumina micro-particles, which, although so widely used and effective, generates pollution, operator health risks, consumes considerable time and labor resources and presents roughness control difficulty. In the other hand, laser texturing is a surface engineering technology based on a pulsed laser which modifies the material surface through melting, evaporation, sublimation and subsequent solidification. This thesis aims to explore the laser texturing effectiveness as an alternative method for substrate surface pre-coating preparation. This process does not generate pollution, allows selective tool areas for processing and, being automated, it potentially requires less time and labor resources. The tools selected for the experiments were two kinds of coated cemented carbide with a composed TiCN+Al2O3+TiN MT-CVD coating and for the experimental substrate surface pre-coating preparation, a pulsed CuHBr laser was used. With the laser process dynamics used, it is possible to control the substrate roughness and to produce a great diversity of surface topographies and structures by adjusting the intensity and/or the amount of laser pulses. Also, it was verified that the laser processing always produces WC (present in the substrate) transformations in new non- stoichiometric phases with less C content. By trial and error method, two laser parameters sets were determined which produced the best adhesion resistance as evaluated through indentation tests: 02 pulses, 410 MW·cm-2 and 64 pulses, 239 MW·cm-2. In dry face milling cutting tests of mould P20 steel with toroidal tools, it was compared the performance of micro-blasted tools (commercial) against laser textured (experimental) ones finding an equal average life for both tool types. Detailed wear mechanisms analysis showed evidences in all the cutting edges of diffusion, attrition, abrasion, deformation, delamination, cracks and a secondary mechanism, called micro-melting wear of the material of the edge. There were no remarkable wear differences between the commercial edges and the experimental ones which could be attributable to the substrate surface pre-coating preparation process
Doutorado
Materiais e Processos de Fabricação
Doutor em Engenharia Mecânica
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Vom, Braucke Troy S., and tvombraucke@swin edu au. "Establishment of a database for tool life performance." Swinburne University of Technology, 2004. http://adt.lib.swin.edu.au./public/adt-VSWT20050914.085324.
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The cutting tool industry has evolved over the last half century to the point where an increasing range and complexity of cutting tools are available for metal machining. This highlighted a need to provide an intelligent, user-friendly system of tool selection and recommendation that can also provide predictive economic performance data for engineers and end-users alike. Such an 'expert system' was developed for a local manufacturer of cutting tools in the form of a relational database to be accessed over the Internet.
A number of performance predictive models were reviewed for various machining processes, however they did not encompass the wide range of variables encountered in metal machining, thus adaptation of these existing models for an expert system was reasoned to be economically prohibitive at this time. Interrogation of published expert systems from cutting tool manufacturers, showed the knowledge-engineered principle to be a common approach to transferring economic and technological information to an end-user. The key advantage being the flexibility to allow further improvements as new knowledge is gained. As such, a relational database was built upon the knowledge-engineered principle, based on skilled craft oriented knowledge to establish an expert system for selection and performance assessment of cutting tools.
An investigation into tapping of austenitic stainless steels was undertaken to develop part of a larger expert system. The expert system was then interrogated in this specific area in order to challenge by experiment, the skilled craft oriented knowledge in this area. The experimental results were incorporated into the database where appropriate, providing a user-friendly working expert system for intelligent cutting tool selection, recommendation and performance data.
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Matsumoto, Hidekasu. "Uma contribuição ao estudo do processo de torneamento de aços endurecidos." [s.n.], 1998. http://repositorio.unicamp.br/jspui/handle/REPOSIP/264206.
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Orientador: Anselmo Eduardo DinizTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica
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Resumo: Neste trabalho procurou-se estudar a viabilidade de se tornear aços no estado endurecido utilizando máquinas de projeto mecânico convencional (sem mancais hidrostáticos e com um certo desgaste) comandadas numericamente, com a finalidade substituir as operações de retificação. Para tanto, usinou-se dois tipos de corpos de prova, de aço ABNT 52100 temperado e revenido com dureza média de 60 HRc (Rockwell C), com ferramentas de corte de PCBN (65% de CBN) e cerâmica mista ('Al IND. 2¿ 'O IND. 3¿ + TiC) encontradas no mercado. Monitorou-se os ensaios via corrente do motor principal e emissão acústica, com a finalidade de determinar o momento da substituição da ferramenta de corte. Após a análise dos resultados, chegou-se às seguintes conclusões: a) é possível substituir as operações de retificação por torneamento com máquina de projeto mecânico convencional, uma vez que se obteve qualidade IT5 e rugosidade menor que Ra = 0,6 'mu¿m, com vidas das ferramentas suficientemente longas para determinadas aplicações; b) os métodos de análise dos sinais de emissão acústica e corrente do motor utilizados, não se mostraram adequados para indicar o momento da troca da ferramenta; c) em geral, a ferramenta cerâmica apresentou vida média maior que a ferramenta de PCBN, porém com uma dispersão também maior
Abstract: The main goal of this work is to study the feasibility of turning hardened steels using a lathe with a conventional mechanical design (without hydrostatic bearings), aiming to replace grinding operations. For this purpose, two kinds of quenched and tempered 52100 steel workpieces were machined, with average hardness of 60 HRc, using PCBN (65% of CBN) and mixed ceramic ('Al IND 2¿¿O IND. 3¿ + TiC) tools. Both the electrical current of the main motor and the acoustic emission were monitored, aiming to automatically establish the moment to replace the tool. After the result analyses, the following conclusions were drawn: a) it is possible to replace grinding operations by turning with a conventional mechanical design lathe, since the workpiece quality obtained was within IT5 and the surface roughness was below Ra = 0.6 ' 'mu¿m, with tool life long enough for this kind of applications; b) the tool life monitoring through acoustic emission and electrical current of the main motor did not show to be suitable to establish the moment to replace the tool; c) in general, mixed ceramic tool had longer average toollife than PCBN tool, but presented larger scatter
Doutorado
Materiais e Processos de Fabricação
Doutor em Engenharia Mecânica
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Pivetta, Carlos Sergio. "Uma contribuição ao estudo do fresamento de aço endurecido com fresa de topo esferico." [s.n.], 2005. http://repositorio.unicamp.br/jspui/handle/REPOSIP/265603.
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Orientador: Anselmo Eduardo DinizDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica
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Resumo: O fresamento de cavidades de moldes e matrizes em material endurecido usando ferramenta de topo esférico tem limitações em termos de profundidades das cavidades, da taxa de remoção de cavaco e da vida da ferramenta. Algumas operações de fresamento em cavidades profundas não podem ser realizadas, devido à necessidade de se ter ferramenta com alto balanço, o que gera vibração e, em conseqüência, danos à rugosidade da peça e à vida da ferramenta. Outro ponto ainda não totalmente compreendido é a influência da rugosidade deixada na peça pela operação anterior, na rugosidade da operação de acabamento, já que, devido às baixas profundidades utilizadas nesta operação, a rugosidade da operação anterior pode influenciar a profundidade real removida. O principal objetivo deste trabalho é verificar a influência da relação comprimento/diâmetro da ferramenta (balanço), da rugosidade da operação anterior e da velocidade de corte na rugosidade da peça e na vida da ferramenta de fresamento em acabamento. Para isto foram realizados ensaios de fresamento em aço endurecido AISI D2 (58 HRC) com ferramenta de ponta esférica de metal duro recoberto, variando-se os citados parâmetros de influência. Dentre as conclusões deste trabalho, pode-se destacar: nem a rugosidade da operação anterior, nem o balanço da ferramenta influenciaram a rugosidade da peça, pelo menos nos níveis utilizados neste trabalho; com balanço da ferramenta pequeno, consegue-se baixos valores de desgaste e, com isso, longa vida da ferramenta, mas quando se utiliza conjuntamente balanço da ferramenta e velocidades de corte altas, a vida da ferramenta é bastante reduzida
Abstract: The milling of molds and dies cavities carried out on hardened steel using ball end mill presents limitations in terms of cavity depth, metal removal rates and tool life. Some milling operations on deep cavities are not possible due to the require of long tool overhang, what generates vibrations and, consequently, resulted in poor surface roughness and short tool life. Other point which is not totally understood up to the present is the influence of the surface roughness obtained in the previous operation on the results of finishing operation because on finishing operations, the actual depth of cut is not much larger than the height of roughness left on the surface by the previous operation. The main objective of this work is to verify the influence of the ratio tool overhang/ tool diameter, the roughness of the previous operation and cutting speed on the tool wear in finishing operations. Besides, it also intends to verify the influence of tool wear on the tool vibration, measured through the real time tool deflection. Milling experiments on AISI D2 hardened steel (58 HRC) were carried out using coated (TiNAl) carbide ball end mills with the input variables already mentioned. The main conclusions of this experiments, for the used conditions, were: the previous surface roughness neither the tool overhang have influence on the resulting surface roughness; when the tool overhang was the lowest one, cutting speed did not influence so much tool wear, but when the highest tool overhang was used, cutting speed presented a strong influence on tool wear
Mestrado
Materiais e Processos de Fabricação
Mestre em Engenharia Mecânica
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Lara, Adriano Perpétuo de. "Análise das vibrações no processo de torneamento interno da liga de alumínio 6351-T6." Universidade Tecnológica Federal do Paraná, 2017. http://repositorio.utfpr.edu.br/jspui/handle/1/2984.
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Este trabalho tem como objetivo analisar as vibrações no processo de torneamento interno utilizando um porta ferramentas com a relação comprimento/diâmetro alta. Ferramentas com alto comprimento em balanço são susceptíveis a ocorrência de vibrações regenerativas durante a usinagem, alterando a estabilidade dinâmica do processo e gerando um acabamento superficial indesejado. Testes realizados para a obtenção de dados foram feitos utilizando equipamentos de medição como microfone e plataforma para medição das forças. A proposta foi de analisar a influência de parâmetros de usinagem como rotação e profundidade de corte na estabilidade dinâmica do processo de torneamento interno da liga de alumínio 6351-T6. Para isso utilizou-se os dados gerados na elaboração de uma carta de estabilidade do processo. Simultaneamente efetuou-se as simulações no software Matlab utilizando um modelo pré-estabelecido e comparando com os resultados experimentais obtidos. Para a análise dos dados coletados pelo microfone utilizou-se uma placa de aquisição de sinais, um microcomputador e um software para análise, o ITA-Toolbox. Baixas velocidades de corte propiciam maiores profundidades de corte limite devido ao efeito de amortecimento. Os resultados mostraram que este fenômeno começa a ser significativo quando a relação entre a frequência de vibração e a frequência de rotação é de aproximadamente 30 e aumenta consideravelmente para uma relação de 60. Os resultados também mostraram que para profundidades de corte abaixo do raio de ponta da ferramenta tem-se cortes instáveis porém de acordo com os modelos existentes na literatura, para um valor suficientemente abaixo da profundidade de corte o processo é sempre estável.This work aims to analyze the vibrations in the boring process using a tool holder with high overhang. Tools with high overhang are susceptible to the occurrence of regenerative vibrations during machining, altering the dynamic stability of the process and generating an undesired surface finish. Tests performed to obtain data were made using measuring equipment such as microphone and platform for measuring forces. The proposal was to analyze the influence of machining parameters such as cutting speed and depth of cut in the dynamic stability of the aluminium alloy 6351-T6 boring process. For this purpose, the data generated in the process stability chart was used. Simulations were performed in the Matlab software using a previous model and compared with the experimental results. For the analysis of the data collected were used a microphone, a signal acquisition board, a microcomputer and a software for analysis, the ITA-Toolbox .In the end, the results showed that the depth of cut and the cutting speed have great influence on the vibration and on the stability of the boring process. Low cutting speeds provide greater cut depth of cut due to the damping effect. The results showed that this phenomenon begins to be significant when the relation between the frequency of vibration and the frequency of rotation is of approximately 30 and increases considerably to a ratio of 60. The results also showed that for depths of cut below the tool nose radius has unstable cuts but according to the models in the literature, for a value sufficiently below the depth of cut the process is always stable.
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Панасюк, А. Г., and A. G. Panasyuk. "Совершенствование технологического процесса обработки корпусной детали высокой сложности «Корпус» с элементами исследования средств технологического обеспечения операций в условиях автоматизированного производства : магистерская диссертация." Master's thesis, б. и, 2020. http://hdl.handle.net/10995/86600.
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The master's thesis consists of three parts: technological, design and research. In the technological part, the improvement of the technological process for the manufacture of basic parts in modern conditions using automated production is considered. In the design part, the development of a mechanized mounting and clamping device for a vertically milling operation and a control and measuring device for a control operation are carried out. In the research part, optimization of cutting conditions for milling a flat surface of the body with milling cutters of various diameters of domestic and foreign manufacturers is given. This part contains a comparison of the milling resistance, determination of the number of workpieces and a comparison of the cost of cutting tools of two manufacturers. The necessary set of design and technological documentation has been formed.Магистерская диссертация состоит из трех частей: технологической, конструкторской и научно-исследовательской. В технологической части рассматривается совершенствование технологического процесса на изготовление корпусной детали в современных условиях с использованием автоматизированного производства. В конструкторской части производится разработка механизированного установочно-зажимного приспособления на вертикально-фрезерную операцию и контрольно-измерительного приспособления на контрольную операцию. В научно-исследовательской части приведена оптимизация режимов резания для фрезерования плоской поверхности корпуса фрезами различного диаметра отечественного и зарубежного производителей. Данная часть содержит сравнение стойкости фрез, определение количества обрабатываемых деталей и сравнение стоимости режущих инструментов двух производителей. Сформирован необходимый комплект конструкторской и технологической документации.
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Santana, Moises Izaias de. "Influência da preparação das arestas de corte de brocas helicoidais no processo de furação." Universidade Tecnológica Federal do Paraná, 2015. http://repositorio.utfpr.edu.br/jspui/handle/1/1419.
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A preparação das arestas de corte é um processo que tem chamado a atenção na indústria de fabricação e recondicionamento de ferramentas em função dos benefícios que tem trazido especialmente na vida útil da ferramenta. Este processo dá um grande diferencial competitivo àqueles que detém o conhecimento de como aplicá-lo e por isso é mantido como um segredo industrial. No que se refere a brocas helicoidais a escassez de informações é ainda maior, em função da alta complexidade da ferramenta e do processo. O presente trabalho traz os resultados da influência da preparação das arestas de corte (alteração da microgeometria) de brocas helicoidais no processo de furação do aço SAE 4144M temperado e revenido com 38 HRC. O processo manual de escovamento foi utilizado para preparar as ferramentas com arestas arredondadas e o processo manual de limagem para as ferramentas com arestas chanfradas. Foram medidas várias características das peças usinadas tais como: diâmetro, circularidade, desvio de posição, rugosidade dos furos obtidos, dureza, microdureza dos corpos-de-prova, força de avanço e torque do processo de furação, avaliação do tipo e forma dos cavacos gerados no processo. Os resultados mostraram que o processo de preparação de arestas aumenta a resistência da ferramenta ao desgaste e consequentemente aumenta sensivelmente sua vida, especialmente as de arestas arredondadas. Além disso, exerce influência na integridade superficial do furo obtido (circularidade e rugosidade) e na microdureza da região próxima à parede do furo obtido. Não houve diferença significativa no torque entre as geometrias analisadas, porém a força de avanço foi menor para a ferramenta apenas afiada sem preparação de aresta.The cutting edge preparation is a process which has drawn attention from the tool’s manufacturing and refurbishing industry due to specialization to its benefits specially to tool useful life. This process results in a major competitive advantage to those who have the knowledge of its application and, for this reason, it is kept as a trade secret. As far as the twist drills are concerned, the scarcity of information is even greater, due to the high complexity of the tool and process itself. This dissertation presents the results of the influence of the preparation of the twist drills cutting edges microgeometry alteration in steel drilling process SAE 4144M quenched and tempered steel with 38 HRC. The manual brushing process was used to prepare tools with rounded edges and manual filing process was used to prepare tools with chamfered edges. Several features from the machined parts were measured, such as diameter, roundness, position deviation, roughness of the obtained holes, hardness and microhardness of specimens, feed force and torque of the drilling process, assessment of type and shape of the chips from the process. The results showed that the edges preparation process increases the wear resistance of the tool and thereby increases its useful life significantly, especially for tools with rounded edges. In addition, it influences the surface integrity of the obtained hole (circularity and roughness) and the hardness of the region near the wall of the obtained hole. There was no significant difference in torque between the analyzed geometries, however the thrust force was lower for the sharpened tool without any edge preparation.
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Крупа, Володимир Васильович. "Металорізальні інструменти з асиметричним розміщенням лез для оброблення глибоких отворів циліндрів." Thesis, Тернопільський національний технічний університет ім. Івана Пулюя, 2015. http://elartu.tntu.edu.ua/handle/123456789/5656.
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Робота виконана на кафедрі конструювання верстатів, інструментів та машин Тернопільського національного технічного університету імені Івана Пулюя Міністерства освіти і науки України. Захист відбудеться 03 липня 2015 р. об 11 годині на засіданні спеціалізованої вченої ради К 58.052.03 у Тернопільському національному технічному університеті імені Івана Пулюя за адресою: 46001, м. Тернопіль, вул. Руська, 56, корп. 2, ауд. 79. З дисертацією можна ознайомитись у науково-технічній бібліотеці Тернопільського національного технічного університету імені Івана Пулюя за адресою: 46001, м. Тернопіль, вул. Руська, 56.Крупа В. В. Металорізальні інструменти з асиметричним розміщенням лез для оброблення глибоких отворів циліндрів. – На правах рукопису. Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.03.01 – процеси механічної обробки, верстати та інструменти. – Тернопільський національний технічний університет імені Івана Пулюя. – Тернопіль, 2015. Розроблені геометрично-математичні та ймовірністно-математичні моделі, які уточнюють вплив кутів в плані, радіусів вершин різальних елементів і подачі на параметр висоти нерівностей профілю обробленої поверхні за десятьма точками. Запропоновано принципи конструкторського виконання і на їх основі розроблено конструкції інструментів з асиметричним розміщенням лез, а саме: три- й чотирирізцеві розточувальні головки та спеціальні чотиризубі зенкери. Особливостями цих інструментів є науково-обґрунтовані значення центральних кутів, які визначають розміщення по колу різальних елементів, та їх оптимізовані й кореговані кути в плані, що забезпечують підвищену продуктивність оброблення при заданій шорсткості обробленої поверхні. Отримано емпіричні залежності, які визначають вплив глибини різання та подачі на осьову силу та крутний момент при обробленні цими інструментами. Здійснено оцінювання впливу подачі на параметр Ra. Запропоновано методику визначення економічної ефективності, яка базується на підвищеній продуктивності оброблення запропонованими інструментами порівняно з обробленням традиційними БМІ.
Крупа В. В. Металлорежущие инструменты с ассиметричным расположением лезвий для обработки глубоких отверстий цилиндров. – На правах рукописи. Диссертация на соискание ученой степени кандидата технических наук по специальности 05.03.01 – процессы механической обработки, станки и инструменты. – Тернопольский национальный технический университет имени Ивана Пулюя. – Тернополь, 2015. Разработаны геометрическо-математические и вероятностно-математические модели, уточняющие влияние углов в плане, радиусов вершин режущих элементов и подачи на параметр высоты неровностей профиля обработанной поверхности по десяти точкам. Предложены принципы конструкторского исполнения и на их основании разработаны конструкции инструментов с асимметричным расположением лезвий, а именно: трех- и четырехрезцовые расточные головки и специальные четырехзубые зенкеры. Особенностями этих инструментов являются научно обоснованные значения центральных углов, определяющих размещение по кругу режущих элементов, и их оптимизированные и корректированные углы в плане, обеспечивающие повышенную производительность обработки при заданной шероховатости обработанной поверхности. Получены эмпирические зависимости, определяющие влияние глубины резания и подачи на осевую силу и крутящий момент при обработке этими инструментами. Осуществлена оценка влияния подачи на параметр Ra. Предложена методика определения экономической эффективности, основанная на повышенной производительности обработки предложенными инструментами по сравнению с традиционными.
Krupa V.V. Metal-cutting tools with asymmetric location of cutters for machining of cylinder deep holes. – Manuscript Dissertation is submitted for the scientific degree of Candidate of Sciences (Engineering) in specialism 05.03.01 – machining processes, machine tools and tools. – Ternopil Ivan Puliuj National Technical University, Ternopil, 2015. The work deals with the development of new principles of multi-cutters design of metal cutting tools with the asymmetric location of cutters, that is, three- and four cutters boring heads and special four-tooth countersinks in order to increase the efficiency of the cylinder deep holes machining by the versatile (multipurpose) screw-cutting lathes (VSCL) and horizontal boring machines. Geometric-mathematic models, which specify the effect of cutting edge angles, cutting element edges radius and the profile roughness height feed according to ten points, have been developed. Basing on the experimentally testified feed stochasticity on the VSCL, which are subject to the normal distribution law, as well as the geometric-mathematic models of the profile roughness height parameters of the method of its estimation has been proposed. Basing on the geometric-mathematic and probability-mathematic models the principles of the construction design of multi-cutters metal cutting tools (MMT) with the asymmetric location of cutters, that is, three- and four-cutters boring heads, which operate in simultaneous distribution of tolerance and feed mode, in which one rough and two or three finishing cutters correspondingly are used, have been developed, as well as special four-tooth countersinks with the pair-asymmetric location of cutters operating according to the feed distribution scheme. General construction characteristic of the proposed MMT is the corrected guting edge angles on the cutting elements. Dependences for finding their technological (feed and cutting depth on every of cutting elements and the feed on revolving) and design (central angles of mutual location of cutting elements corrected angles) parameters, have been proposed. For four-cutters boring heads the model of the angles value optimization has been presented, providing the maximum efficiency of machining. The options of these MMT designs have been presented, which had been applied at the joint venture «Kamianets-Podilskautoagregat». The analysis of the available methods of investigation has been carried out as well as the estimation of the power characteristics of the machining process and the roughness of the machined surface deep holes. Experimental equipment for testing the power characteristics of the MMT deep holes machining has been developed, special chuck in particular, for fixing thin-walled blank – hollow cylinders with deep holes, special dynamo-metric device, and the available device for testing on the screw-cutting lathe of 1M63-type, has been improved. The method of experimental determination of the power characteristics of the MMT deep holes machining with the asymmetric location of cutters taking advantage of the theory of the experiment planning, has been developed. Taking into account the feeds stochasticity, the empiric dependencies for average values of the axis force and the torque, as well as their maximal values have been obtained. It was found that while machining by the countersinks with the pair-asymmetric location of cutters the axis force is by 15.2% greater and the torque by 22.6% smaller as compared with those in conventional tools. As a result of estimation of the feed effect on the Ra parameter it was found, that the optimal feed for countersinks with the pair-asymmetric location of cutters is the feed s=0.35 mm/rev. The method for finding the economic effectiveness of machining the cylinder deep holes surfaces taking advantage of the proposed engineering solutions, obtained due to the increase of the machining efficiency providing the given values Ra, has been developed. Key words: multicutters metal-cutting tools, asymmetric cutters location, countersink, boring head, cutting edge angles, cutter, feed, cutting depth, roughness.
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Ghadimzadeh, Seyed Reza. "Machining of hypereutectic aluminium-silicon alloy." Thesis, Coventry University, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.281726.
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Reeswinkel, Thomas [Verfasser]. "Self-lubricious tool coatings for ecological metal cutting / Thomas Reeswinkel." Aachen : Shaker, 2012. http://d-nb.info/1069046663/34.
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Erkers, Louise. "Chemical Interactions between tool and Aluminium alloys in metal cutting." Thesis, KTH, Materialvetenskap, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-291358.
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Aluminium applications in automotive will increase by 25 % over the next decade, mainly driven by the electrification and the reduction of fuel consumption. This diploma work aims to increase the understanding of the chemical interactions between aluminium alloys and typical tool systems in metal cutting. First the temperature at the tool-chip interface was estimated by FEM simulations, using the software AdvantEdge. Thereafter the chemical interaction of the tool-chip interface was calculated at the simulated temperature using the Thermo-Calc software. The thermodynamic data and descriptions of the multicomponent systems used where found in the literature, assessed by other authors, but critically reviewed for the use in this work. The results of the FEM simulations indicate that the temperature for machining aluminium with PCD and cemented carbide is between 60-80 % of the melting temperature of Al7wt %Si alloy. The calculations of the chemical interaction in turn results in that several hard precipitates can stick to or transform on the surface of the workpiece or tool-chip interface, for example SiC, Al4C3 and evidently diamond from the tool. This work concluded that more predictive modelling is needed to refine the results and the results from this work needs to be confirmed with experiments. The results show that the modelling can predict the reaction phases at the tool-chip interface, this can be used as input for the tool wear mechanisms during development of tooling solutions.Aluminium användningen inom fordonsindustrin förväntas öka med 25 % under det närmsta decenniet, främst på grund av elektrifiering men också för att för att minska bränsleförbrukning. Målet med detta examensarbete är till att öka förståelsen för de kemiska interaktionerna mellan aluminiumlegeringar och typiska verktygssystem vid metallskärning, framförallt vid bearbetning av aluminiumlegeringar innehållande kisel med ett TiN-belagt PCD-verktyg och icke-belagda verktyg. Detta gjordes genom prediktiva FEM-simuleringar av temperatur, med hjälp av mjukvaran AdvantEdge. Parallellt med detta skapades databaser för simulering av den kemiska interaktionen mellan skär och bearbetningsmaterial i programvaran Thermo-Calc. De termodynamiska data och beskrivningarna av de termodynamiska system som används var bedömda av andra författare men kritiskt granskade för användning i detta arbete. Resultaten av FEM-simuleringarna gav den beräknade temperaturen för bearbetning av aluminium med PCD ligger någonstans mellan 60-80 % av smälttemperaturen för Al7wt % Si-legering. Beräkningarna av den kemiska interaktionen resulterar i sin tur i att flera hårda utskiljningar kan fastna på eller transformera på ytan mellan arbetsstycket och verktyget, till exempel SiC, Al4C3och diamant från verktyget. Resultaten från detta arbete visar att det går att förutsäga fasomvandlingar mellan skär och arbetsstycket, samt att detta kan användas som indata för skärförslitning under utvecklingen av verktygslösningar.
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Tsui, Kin-shing. "Tool path generation for protrusion milling." Click to view the E-thesis via HKUTO, 2006. http://sunzi.lib.hku.hk/hkuto/record/B36891332.
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Dimla, Dimla E. "Multivariate tool condition monitoring in a metal cutting operation using neural networks." Thesis, University of Wolverhampton, 1998. http://hdl.handle.net/2436/96291.
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Shatla, Mahmoud Nagui. "Prediction of forces, stressses, temperatures and tool wear in metal cutting." The Ohio State University, 1999. http://rave.ohiolink.edu/etdc/view?acc_num=osu1251224746.
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Shatla, Mahmoud Nagui. "Prediction of forces, stresses, temperatures and tool wear in metal cutting /." The Ohio State University, 2000. http://rave.ohiolink.edu/etdc/view?acc_num=osu148819211926358.
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Okeke, Christopher Igwedinma. "Threading and turning of aerospace materials with coated carbide inserts." Thesis, London South Bank University, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.297919.
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The first part of this study involve an evaluation of the performance of TiN and AlZ03 single layer coated cemented carbide tools when threading inclusion modified, 708M40T (En 19T) 817M40T (En 24T) and Jethete steels at high cutting conditions by monitoring tool wear, failure modes, post threading workpiece properties, micro and macro-surface alterations and subsurface microhardness variation of threaded surfaces. Test results show that flank wear was the dominant failure mode, increasing rapidly when machining at the top speed of 225 m min,l due to the high temperature generated which accelerates thermally related wear mechanisms. Tool life, surface finish, hardness variation and component forces during threading were influenced by the geometry of the cutting edge, shape of wear/length of wear along tool nose/cutting edge after threading. Formation of flake-like oxide debris on the worn inserts was found to increase with nickel content in the workpiece material. The Al20) coated carbide inserts with K05 - K20 substrate gave longer tool life, lower cutting forces, better surface finish! damages as well as minimum hardness variation after threading compared with the TiN coated VSX grade with P20-P30 substrates. This can be related to their superior hardness, density, transverse rupture strength as well as the unalloyed WC fine grained substrate (1/lm) in addition to the high hot hardness, excellent chemical stability and low thermal conductivity of the AlZ03 coating at elevated temperatures. A formula for tool rejection was also developed during this study based on the average flank wear (VBb) and growth in thread root (GTR) in order to establish a scientific basis for assessing wear of threading tools. The second part of this study involve single point turning of a nickel base, G263, alloy using rhomboid-shaped PVD coated (TiN/TiCN/TiN, TiAIN and TiZrN) carbide tools at high speed cutting conditions. The worn tool edges revealed adhesion of a compact fin-shaped structure of hardened burrs with saw-tooth edges. The compact structure also formed on the cut surface of the workpiece material. The use of coolant during machining tend to work harden the root of the burr thereby restricting tool entry at the cutting zone leading to the generation of excessive feed force which subjects the tool edge to premature fracture and consequently lower tool life. The serrated/saw-tooth like edges of the burr encourages abrasion wear on the tool flank face and the formation of shallow cavities/lateral cracks where fragments of hardened workpiece material are deposited causing deterioration of the machined surfaces. Tool life was generally influenced by the cutting conditions employed as well as the insert geometry. Increasing cutting conditions (speed, feed and depth of cut) led to chipping of the cutting edge and/or flaking of coating layers as well as notching and fracture of the cutting edge. These failure modes jointly contributed to lowering tool life during machining. The TiN/TiCN/TiN coated KC732 (Tool A) inserts with positive sharp edges gave overall performance at the optimum cutting conditions established under finishing operation. This is followed by the TiN/TiCN/TiN coated KC732 (Tool B), TiAlN coated KC313 (Tool C) and lastly the TiZrN coated KC313 (Tool D) inserts' with razor sharp edges. Under roughing operation, the ranking order of tool performance is the TiZrN coated KC313 (Tool D), TiN/TiCN/TiN coated KC732 (Tool A), TiAlN coated KC313 (Tool C) and lastly the TiN/TiCN/TiN coated KC732 {Tool B). The difference in tool geometry and coating materials contributed to the relative order of tool performance.
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Lindbäck, Daniel. "Investigating a change of material on turning tools with Coromant Capto ® interface : A study conducted at Sandvik Coromant in Gimo." Thesis, Luleå tekniska universitet, Produkt- och produktionsutveckling, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-64011.
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Sandvik Coromant is the leading supplier of cutting tools and solutions to the machining industry. Sandvik Coromant is the creator of the modular Coromant Capto ® tool interface which have since become an ISO-standard. The Coromant Capto ® interface, which currently is undergoing a revision is found in the machining applications turning, milling and drilling because of its unique characteristics. Sandvik Coromant's largest factory for cutting tools is located in Gimo which produces tools with the Coromant Capto ® interface for milling and turning applications. The turning tools with the Coromant Capto ® interface are currently produced from the tool steel 25CrMoS4, commonly known as SS2225 with a typical initial hardness of 28 ± 2 HRC. To achieve the required hardness of the finished tools, the turning tools are hardened by induction which results in hardness levels close to, or above 50 HRC. These induction hardening processes which are carried out after the machining operations induces geometrical distortions in the tools which impacts the quality of the finished product. Furthermore it is expected that the new revision of the Coromant Capto ® interface will be dificult to produce due to these geometrical distortions. To avoid the geometrical distortions due to induction hardening a change of material was examined. The turning tools with the Coromant Capto ® interface would instead be produced from the tool steel 34CrNiMo6, commonly known as SS2541. SS2541 is currently being used as material for the milling tools produced in Gimo. The tool steel SS2541 would imply a new process flow for the turning tools which would be hardened to 43,5 ± 2 HRC before the machining operations in a furnace thus avoiding the geometrical distortions. The purpose of the thesis was to study and predict the impacts and the changes that this new production process flow would lead to. The hypothesis of the whole study was claried as:"The change of material in Coromant Capto ® -equipped turning tools would be benecial in terms of the complete picture". To either prove or disprove the hypothesis research was conducted in three separate studies namely Quality, Time and Cost. A case study was used to compare the different process flows with each other. A sample of seven turning tools was studied within the case study. Each tool in the sample represents a portion of the real production volumes produced in Gimo. It was found that both product and process quality would increase with the material SS2541. Product quality would increase because the geometrical distortions would be avoided. This would increase value for the end customer which could expect a more predictable machining process. Process quality would also increase, mainly because control measurements will be carried out in a better way than in the current situation, and the fact that a simpler process flow with less operations will be true for SS2541. Process time increased for almost all material removal operations because the higher hardness of the material SS2541. Total process time would increase for the blanks and would decrease for the tools because the hardening operation are moved from tool to blank. The throughput rate of both blanks and tools will decrease, because the constraining operations or bottleneck operations would take longer time. Despite this it is expected that machine capacity is sufficient for producing the current production volumes from the material SS2541. The production cost for all tools in the sample will increase, one of the tools by as much as 11%. Production cost for a yearly production of turning tools (blanks included) is estimated to increase with 5%. The highest contributing factor to the increased cost is the initial cost of the material which will increase with 10%. To minimize the impact of material cost the range of blanks should be rationalized, i.e producing more tools from forged blanks instead from round blanks. To summarize and give an recommendation: The hypothesis of the thesis is confirmed. The change of material to SS2541 would seen to the complete picture prevent many problems to a relatively low cost. Therefore it is recommended that the material is changed from SS2225 to SS2541.Sandvik Coromant är en ledande tillhandahåallare av verktyg och lösningar till bearbetningsindustrin. Sandvik Coromant uppfann det modulära verktygsgränssnittet Coromant Capto ®, vilken på senare år har blivit en ISO-standard. Coromant Capto ®-kopplingen, som för tillfället undergår en revision återfinns, tack vare sina unika egenskaper inom applikationsområdena svarvverktyg, fräsverktyg och borrverktyg. Sandvik Coromants största fabrik för skärande verktyg ligger i Gimo i vilken man tillverkar både svarvverktyg och fräsverktyg med Coromant Capto ®-koppling. Svarvverktygen med Coromant Capto ®-koppling tillverkas nuvarande från verktygsstålet 25CrMoS4, allmänt känt som SS2225, vilket har en typisk grundhårdhet på ca 28 ± 2 HRC. För att uppnå rådande hårdhetskrav induktionshärdas svarvverktygen med induktionshärdning vilketresulterar i hårdheter nära- elleröver 50 HRC. Dessa induktionshärdningsprocesser utförs efter bearbetningsoperationerna och skapar formförändringar i verktygen, vilket i sin tur påverkar kvaliteten för den slutgiltliga produkten. Dessutom förväntas det att tillkomma problem med att tillverka den nya Coromant Capto ®-revisionen på grund av formförändringarna. För att förebygga formförändringarna som tillkommer vid induktionshärdningsprocesserna studerades ett materialbyte. Svarvverktygen med Coromant Capto ®-kopplingar skulle nu produceras från verktygsstålet 34CrNiMo6, allmänt känt som SS2541 istället. SS2541 används för närvarande till fräsprodukterna som produceras i Gimo. Verktygsstålet SS2541 skulle innebära ett nytt processflöde för svarvverktygen vilka nu skulle ugnshärdas före bearbetningsoperationerna till en hårdhet av 43,5 ± 2 HRC och på så sätt undvika formförändringarna. Syftet med examensarbetet var att utreda och förutspå effekterna och förändringarna som detta nya processflöde skulle innebära. Hypotesen till hela studien sammanfattades som: Materialbytet på svarvverktyg med Coromant Capto ®-koppling skulle vara positivt sett till helheten. För attantingen bekräfta eller dementera denna hypotes utfördes en studie som innefattade tre separata utredningar inom områdena Kvalitet, Tid och Kostnad. Man använde sig av en fallstudie för att jämföra de olika processflödena med varandra. Ett urval bestående av sju produkter studerades inom denna fallstudie. Varje produkt från urvalet fick representera en delvolym av den totala årliga produktionsvolymen i Gimo. Man fann att både produktkvalitet och processkvalitet skulle öka till följd av materialbytet till SS2541. Produktkvaliteten skulle öka för att formförändringarna skulle undvikas. Detta skulleöka värdet för slutkunden, vilken kan komma att förvänta sig en bättre och mer förutsägbar bearbetningsprocess. Processkvaliteten skulle också öka, främst för att kontrollmätningar nu skulle kunna utföras på ett bättre sätt än man kan göra i det nuvarande processflödet samt att flödet skulle bli enklare och tydligare med färre processteg. Processtider skulle öka för nästan alla bearbetningsoperationer på grund av att SS2541 har en högre hårdhet. Den totala processtiden skulle öka förämnestillverkningen och minska för verktygstillverkningen för att härdningsoperationerna förflyttas från verktyg till ämne. Genomströmmningshastigheten skulle minska för både ämne och verktyg för att flaskhalsarna i produktionen skulle ta längre tid. Dock skall tilläggas att man fortfarande skulle ha kapacitet nog föratt tillverka dagens produktionsvolymer i materialet SS2541. Produktionskostnaden för alla produkterna i urvalet skulle öka, varav en produkt skulle öka med så mycket som 11%. Produktionskostnaden för en årsproduktion av svarvverktyg (ämnesproduktion inräknad) uppskattades att öka med 5%. Den största faktorn till den ökade produktionskostnadenär initialkostnaden för materialet som kommer att öka med 10%. För att minimera effekterna av materialkostnaden borde ämnesfloran rationaliseras, alltså producera fler verktyg från smidda ämnen än från försvarvade ämnen. För att sammanfatta och ge en rekommendation: Hypotesen kan bekräftas. Materialbytet till SS2541 skulle, sett till helheten förebygga många problem till en relativt låg merkostnad. Därför rekommenderas att materialbytet från SS2225 till SS2541 genomförs.
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Sadek, Hassan Ramadan Mohammed. "The adaptive control of tool force during roughing operations in continuous metal cutting." Thesis, University of Southampton, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.358361.
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Yen, Yung-Chang. "Modeling of metal cutting and ball burnishing prediction of tool wear and surface properties /." Columbus, Ohio : Ohio State University, 2004. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1073065455.
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Thesis (Ph. D.)--Ohio State University, 2004.Title from first page of PDF file. Document formatted into pages; contains xxviii, 254 p.; also includes graphics. Includes abstract and vita. Advisor: Taylan Altan, Dept. of Industrial and Systems Engineering. Includes bibliographical references (p. 240-248).
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Ånmark, Niclas. "Steel characteristics and their link to chip breaking and tool wear in metal cutting." Doctoral thesis, KTH, Tillämpad processmetallurgi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-187156.
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The vision of this thesis is to study how it is possible to obtain optimised workpieces during metal cutting processes in industry. Specifically, the work is aimed to increase the understanding between the steel characteristics and their link to the chip breaking and tool wear during metal cutting. The emphasis is on the influence of the cleanliness and the characteristics of non-metallic inclusions in the workpiece on the machinability of carburising steel grades. The machinability of a case hardening steel is improved by a M-treatment (additions of Ca). Also, the improved machinability of the M-steels offers an attractive potential to save money which makes it possible to reduce the tooling costs with up to 50%. The improved machinability of Ca-treated steels is correlated to the formation of lubricating slag layers consisting of Ca-enriched sulfide inclusions and oxy-sulfide inclusions, which are formed on the rake face during the machining operation. It is proposed that the formations of slag layers from the workpiece constituents are essential to minimise the chemical degradation of the tool edge due to a contact with the chip. During this process, sulfur minimises the material transfer from the chip flow, whilst Ca-treated impurities have a stabilising effect on the protective deposits made of slag layers. Since there is a remaining industrial need to increase the production rate, whilst maintaining a high quality of the finished parts, the future production will continue to require extreme demands on the quality of workpieces. If the emphasis is focused on the workpiece, it should be possible to obtain a robust manufacturing process. Therefore, the challenge for future steel metallurgists is to develop high performance grades with optimised combined properties.Syftet med denna avhandling är att studera hur det är möjligt att framställa optimala ämnen för skärande bearbetning i industriell skala. Målsättningen med arbetet är att öka förståelsen för ståls egenskaper och dess inverkan på spånbrytning och slitage av verktyg vid skärande bearbetning. Avhandlingen fokuserar på kopplingen mellan arbetsstyckets renhet och inneslutningskarakteristik och dess inverkan på skärbarhet hos sätthärdningsstål. Skärbarheten hos vanligt sätthärdningsstål kan förbättras markant genom en Ca-behandling, dvs. en så kallad M-behandling. Den förbättrade skärbarheten hos M-stål möjliggör stora kostnadsbesparingar, som uppskattas kunna reducera verktygskostnader med upp till 50%. Den förbättrade skärbarheten hos M-stål beror på bildningen utav tribologiska skikt som är anrikade med (Mn,Ca)S- och (CaO)x-Al2O3-S-slagg. Dessa tribologiska skikt bildas på skärverktygets spånsida under ingrepp vid skärande bearbetning och består utav vissa atomer som överförts från det bearbetade ämnet till skäret. Bildandet av ett skyddande skikt anses nödvändigt för att undvika att verktygets skäregg utsätts för ett kemiskt angrepp i kontaktytan med spånflödet. Svavel anses minimera att rent arbetsmaterial överförs till skärverktyget medans kalcium-berikade inneslutningar hjälper till att bilda ett stabilt och skyddande tribologiskt skikt. Det eviga behovet att öka produktionstakten, utan att för dess skull riskera slutproduktens kvalité ställer stora krav på framtidens material. Med utgångspunkt från arbetsstycken så ska det vara möjligt att uppnå en robust industriell produktion. Utmaningen är därför att utveckla högpresterande stål med en förhöjd kombinerad funktionsegenskap.
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Ammer, Khan Ammer Khan. "Metal to ceramic joining for high temperature applications." Thesis, Brunel University, 2003. http://bura.brunel.ac.uk/handle/2438/5375.
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The phenomenal growth rate for the use of engineering ceramics is attributed to successful scientific responses to industrial demand. These materials are replacing metal and its alloys in diverse applications from cutting tools and heat engine components to integrated circuits. Joining technology plays a vital role in this changing and evolving technology as success and failure comes with breaking new barriers. It is important to improve existing techniques and to develop new techniques that reliably join simple shape components to form complex assemblies or join dissimilar materials such as metal to ceramic. Joining of ceramics is not simple due to their high chemical stability and low coefficient of thermal expansion (CTE). Joining between metal and ceramic is usually carried out at elevated temperatures and upon cooling thermal residual stresses are induced that lead to joint failure or poor strength. Most metal-ceramic joints cannot be used over 500°C primarily due to the low melting temperature of the interlayer. This investigation was concerned with the successful joining for higher temperature applications (above 500°C) of two dissimilar high temperature oxidation and corrosion resistant materials, Fecralloy and silicon nitride. The primary focus was on the effects of process conditions upon the microstructure and mechanical properties of the joint and to also study/identify the joining mechanism. Two novel techniques were employed to join successfully the metal to ceramic. The first was by use of a thin Cu foil that did not remain after joining. Joining occurs by a process that results in partial melting of the Fecralloy interface, where Fe, Cr, Al and Cu reactively infiltrate into the silicon nitride. This liquid mixture causes partial dissolution of the silicon nitride interface, where Si and N diffuse into the Fecralloy. A thin reaction product layer was formed at the silicon nitride interface and our results suggested that this was AIN. The free surface Si and porosity of the silicon nitride along with the eutectic temperatures above 1100°C are all vital for this joining process. The highest average shear strength of a Fecralloy-silicon nitride joint produced by the method was 67.5 MPa. The second route was that of a powder metallurgy one, where cold pressed Ni-Al (1:1 molar) compacts were used to join successfully the Fecralloy to silicon nitride. The formation of NiAl from its constituents is highly exothermic and this is initiated between 500-650°C. The high temperature reached causes partial melting of the Fecralloy interface and dissolution/reactive wetting at the silicon nitride interface. Mostly Fe infiltrates the NiAl improving room temperature ductility, fracture toughness and yield strength. Molten Al from the interlayer reacts and wets the silicon nitride interface with small amount of infiltration and no reaction product forming. The reaction synthesis of NiAl was studied using DTA and TGA, where the effects of Ni particle size and heating rate were investigated. This joining process is highly dependant upon process conditions, the most important of which are applied pressure, heating rate and Ni/A1 particle size. The highest average shear strength attained was 94.30 MPa and this is attributed to good interfacial bonding, high pressure, moderate process temperature and dwell time. The exothermic formation of the NiAl interlayer that is densified and monophase was paramount for this joining process. The Bansal-Doremus kinetic model for evaluating the kinetic parameters from non-isothermal DTA data was shown to be valid. The results obtained were identical to those by other authors who used a different model and approach.
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Tsui, Kin-shing, and 徐健成. "Tool path generation for protrusion milling." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2006. http://hub.hku.hk/bib/B36891332.
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Sveen, Susanne. "Wear of coated and uncoated PCBN cutting tool used in turning and milling." Licentiate thesis, Linköpings universitet, Nanostrukturerade material, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-102551.
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This licentiate thesis has the main focus on evaluation of the wear of coated and uncoated polycrystalline cubic boron nitride cutting tool used in cutting operations against hardened steel. And to exam the surface finish and integrity of the work material used. Harder work material, higher cutting speed and cost reductions result in the development of harder and more wear resistance cutting tools. Although PCBN cutting tools have been used in over 30 years, little work have been done on PVD coated PCBN cutting tools. Therefore hard turning and hard milling experiments with PVD coated and uncoated cutting tools have been performed and evaluated. The coatings used in the present study are TiSiN and TiAlN. The wear scar and surface integrity have been examined with help of several different characterization techniques, for example scanning electron microscopy and Auger electron spectroscopy. The results showed that the PCBN cutting tools used displayed crater wear, flank wear and edge micro chipping. While the influence of the coating on the crater and flank wear was very small and the coating showed a high tendency to spalling. Scratch testing of coated PCBN showed that, the TiAlN coating resulted in major adhesive fractures. This displays the importance of understanding the effect of different types of lapping/grinding processes in the pre-treatment of hard and super hard substrate materials and the amount and type of damage that they can create. For the cutting tools used in turning, patches of a adhered layer, mainly consisting of FexOy were shown at both the crater and flank. And for the cutting tools used in milling a tribofilm consisting of SixOy covered the crater. A combination of tribochemical reactions, adhesive wear and mild abrasive wear is believed to control the flank and crater wear of the PCBN cutting tools. On a microscopic scale the difference phases of the PCBN cutting tool used in turning showed different wear characteristics. The machined surface of the work material showed a smooth surface with a Ra-value in the range of 100-200 nm for the turned surface and 100-150 nm for the milled surface. With increasing crater and flank wear in combination with edge chipping the machined surface becomes rougher and showed a higher Ra-value. For the cutting tools used in milling the tendency to micro edge chipping was significant higher when milling the tools steels showing a higher hard phase content and a lower heat conductivity resulting in higher mechanical and thermal stresses at the cutting edge.
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Marques, Armando. "Torneamento de Inconel 718 com aplicação de lubrificantes sólidos." Universidade Federal de Uberlândia, 2015. https://repositorio.ufu.br/handle/123456789/14776.
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Fundação de Amparo a Pesquisa do Estado de Minas GeraisThe nickel-based superalloys have a high mechanical strength which remains at elevated temperature, high creep and fatigue resistances and excellent oxidation resistance. This makes these alloys highly recommended for use in high temperature working environments such as mechanical components for the aerospace industry. However, these characteristics are major problems when machining them, as it promotes high heat generation in the flow zone, resulting in the development of high wear rates on the cutting tools. In order to reduce the problems caused by the high temperatures generated, the application of a cutting fluid, when possible, is essential to reduce friction at the chip-tool-workpiece interfaces and lower the temperatures in the cutting zone. Seeking to further increase in the efficiency of cutting fluids during machining of nickel alloys, this work presents a study of the influence of solid lubricants, graphite and molybdenum disulphide (MoS2) mixed to a vegetal based cutting fluid, applied by conventional method (flooding) and minimal quantity of fluid - MQF in turning of Inconel 718 with carbide and ceramic (mixed, whisker and SiAlON) tools. When turning with cemented carbide tools the addition of graphite to the cutting fluid provided the best results, while with ceramic tools MoS2 presented the best performance. The life of the carbide tool had an average increase above 200% in conventional flooding application of cutting fluid when compared to MQF, regardless the addition of solid lubricant. The addition of solid lubricants promoted an increase in the life of whisker and SiAlON tools. The flank wear was dominant for cemented carbide tools and SiAlON ceramics, while for whisker and mixed ceramics the notch wear was predominant. Attrition and diffusion wear mechanism were observed in all evaluated conditions. The addition of solid lubricant to the cutting fluid provided significant improvements in the surface roughness values for most of the evaluated conditions. However, there were no significant changes in the machining forces and cutting temperature. The residual stress was tensile and compression, depending on the fluid application method. Overall, the addition of solid lubricant showed no significant differences.
As superligas à base de níquel apresentam alta resistência mecânica que se mantém em elevadas temperaturas, altas resistência à fluência e à fadiga e excelente resistência a oxidação. Isso torna estas ligas altamente recomendadas para utilização em ambientes que trabalham a altas temperaturas, como por exemplo na fabricação de componentes mecânicos para a indústria aeroespacial. Entretanto, esta característica representa um grande problema quando elas são usinadas, pois promove elevada geração de calor na zona de fluxo, implicando no desenvolvimento de altas taxas de desgaste da ferramenta de corte. A fim de reduzir os problemas causados pelas altas temperaturas geradas, a aplicação de um fluido de corte, quando possível, é essencial, proporcionando redução do atrito na interface cavaco-ferramenta-peça e menores temperaturas na zona de corte. Na busca de aumentar ainda mais a eficiência dos fluidos de corte na complexa usinagem das ligas de níquel, este trabalho apresenta um estudo da influência dos lubrificantes sólidos grafite e bissulfeto de molibdênio (MoS2) misturado a um fluido de corte de base vegetal, aplicados pelo método convencional (jorro) e mínima quantidade de fluído MQF, no torneamento do Inconel 718, com ferramentas de metal duro e cerâmicas (mista, whisker e SiAlON). No torneamento com ferramentas de metal duro a adição de grafite ao fluido de corte proporcionou os melhores resultados, enquanto que no torneamento com ferramentas cerâmicas, foi o MoS2 que apresentou melhor desempenho. A vida da ferramenta de metal duro teve um incremento acima de 200% na usinagem convencional (jorro) quando comparado com a usinagem por MQF, sem considerar a adição do lubrificante sólido. A adição de lubrificantes sólidos promoveu um incremento na vida das ferramentas whisker e SiAlON. O desgaste de flanco foi predominante para as ferramentas de metal duro e cerâmica SiAlON, enquanto que nas cerâmicas whisker e mista o desgaste de entalhe foi predominante. Os mecanismo de desgaste de attrition e difusão foram observados em todas as condições avaliadas. A adição de lubrificante sólido ao fluido de corte proporcionou melhorias significativas nos valores da rugosidade para a maioria das condições avaliadas. No entanto, não se observou mudanças significativas nas forças e temperatura de usinagem. As tensões residuais foram de tração e compressão, dependendo do método de aplicação do fluido. No geral, a adição do lubrificante sólido não apresentou diferenças significativas.
Doutor em Engenharia Mecânica
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Ånmark, Niclas. "Inclusion Characteristics and Their Link to Tool wear in Metal Cutting of Clean Steels Suitable for Automotive Applications." Licentiate thesis, KTH, Tillämpad processmetallurgi, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-164875.
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This thesis covers some aspects of hard part turning of carburised steels using a poly‑crystalline cubic boron nitride (PCBN) cutting tool during fine machining. The emphasis is on the influence of the steel cleanliness and the characteristics of non‑metallic inclusions in the workpiece on the active wear mechanisms of the cutting tool. Four carburising steel grades suitable for automotive applications were included, including one that was Ca‑treated. A superior tool life was obtained when turning the Ca-treated steel. The superior machinability is associated with the deposition of lubricating (Mn,Ca)S and (CaO)x-Al2O3-S slag layers, which are formed on the rake face of the cutting tool during machining. Moreover, the transfer of work material to the rake face crater is characteristic in hard part turning of clean steels. It can be because of the lack of sulfides that protect the cutting edge when turning machinability treated steels. This corresponds to the more pronounced crater wear caused by the low‑sulfur steels than that of the steels with higher sulfur contents. It was also concluded that the composition of the non‑metallic inclusions in the Ca‑treated steel is a more important factor than the inclusion number and size, in hard part turning using a PCBN cutting tool. Also, a 3D analysis after electrolytic extraction was found to give a more precise characterisation of non‑metallic inclusions than the conventional 2D analysis by SEM‑EDS. In turn, better correlations to machinability and mechanical properties can be obtained. Hence, the use of this technique is beneficial for future material development. Finally, the challenge for future metallurgy is to manufacture high‑performance steels with improved combined properties of mechanical strength and machinability.QC 20150422
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Dhulubulu, Aditya. "Acoustic Emission (AE) monitoring of the milling process with coated metal carbide inserts using TRIM C270 cutting fluid." University of Toledo / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1435592338.
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Дегтярьов, Іван Михайлович, Иван Михайлович Дегтярев, Ivan Mykhailovych Dehtiarov, Віталій Олександрович Іванов, Виталий Александрович Иванов, Vitalii Oleksandrovych Ivanov, and І. О. Криводуд. "Аналіз технологічних можливостей сучасних свердлильно-фрезерно-розточувальних верстатів." Thesis, Сумський державний університет, 2014. http://essuir.sumdu.edu.ua/handle/123456789/39644.
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У даний час, в умовах швидкого впровадження інноваційних технологій у машинобудуванні, використання металорізального обладнання, яке відповідає сучасним стандартам, є невід’ємною частиною кожного
машинобудівного підприємства. Раціональний вибір верстатів та їх ефективне використання дозволяє випускати конкурентоспроможну продукцію. Метою даної наукової роботи є проведення статистичного аналізу верстатів свердлильно-фрезерно-розточувальної групи з подальшим формуванням бази даних і розробленням рекомендацій щодо їх ефективного використання у промисловості.
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Kráčmar, Lukáš. "Výroba nástěnného držáku televizoru." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2016. http://www.nusl.cz/ntk/nusl-241723.
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This master’s thesis conducted within the master's degree focuses on the design of production for component, which is a wall-mount the TV. The blank is sheet steel DC03 and the annual production is 300,000 pieces. After exploring possible options of manufacturing was chosen compound tool. In the theoretical part were explored technology used cutting and bending. Further, the manufacturing process and tool design were made. The suitability of the solution was verified by economic evaluation.
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Kvapil, Jan. "Návrh stroje pro stříhání a ohýbání vybrané součástky." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2013. http://www.nusl.cz/ntk/nusl-230631.
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KVAPIL Jan: Bending and cutting press machine for representativ part The Master´s thesis, which is developer in an undergraduate degrese in M-VSR, provides a brief overview and description of the cutting and bending technology. The thesis is carried out the calculation, which is essential for the design cutting and bending tools. Models and design are created in the software SolidWorks 2012. The Master´s thesis includes a general procedure after the award until after copy the parts on it.
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Svozilová, Lucie. "Výroba kovového třmenu zásuvky sdruženým nástrojem." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2021. http://www.nusl.cz/ntk/nusl-445158.
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The project elaborated design of technology production of the metal yoke of electrical socket made of steel DX51D + Z200 by compound progressive tool. Stock material for series of 200 000 pieces is a strip of coil. Manufacturing is realised in five steps consist of cutting, bending and flanging. For flanging was constructed a special mechanism for whose is necessary to use hydraulic counterholder, which is sold as a special peripheral equipment of manufacturing machine. The machine choice was adapted to this criterium. The servopress DSF-N1-800A was chosen as a manufacturing machine, which is made by AIDA company. The press can produce force of 800 kN and make work of 4000 J. Selling price of a one yoke is 24,5 Kč when the profit is one hundred percent. The break-even point comes with 58 140 made piece.
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Ručka, David. "Konstrukce lisovacího nástroje pro součást z plechu." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2011. http://www.nusl.cz/ntk/nusl-229681.
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The in the framework of Master’s Studies developed project presents a technology- proposal for the production of a pressing tool for the manufacturing of parts from the sheet steel DD13. On the basis of a literary survey of problems of the component manufacturing through shearing, bending and the studies of heat treatment and applications of covering coat and calculation, manufacturing in the phase-shearing tool was proposed. The press GERB EDELHOFF 80 t was selected as the working device.