Tesis sobre el tema "Nitriding"
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Fitz, T. "Ion nitriding of aluminium". Forschungszentrum Dresden, 2010. http://nbn-resolving.de/urn:nbn:de:bsz:d120-qucosa-29382.
Texto completoFitz, T. "Ion nitriding of aluminium". Forschungszentrum Rossendorf, 2002. https://hzdr.qucosa.de/id/qucosa%3A21765.
Texto completoYang, Mei. "Nitriding - fundamentals, modeling and process optimization". Digital WPI, 2012. https://digitalcommons.wpi.edu/etd-dissertations/127.
Texto completoLiu, Wendi. "The effects of contaminants on the gas nitriding of Nitralloy-135". Worcester, Mass. : Worcester Polytechnic Institute, 2008. http://www.wpi.edu/Pubs/ETD/Available/etd-112408-113232/.
Texto completoCrust, Glen Alexander. "The nitriding of high speed steel cutting tools". Thesis, University of Plymouth, 1989. http://hdl.handle.net/10026.1/2379.
Texto completoBennett, Robert. "The plasma nitriding of tool and bearing steels". Thesis, Aston University, 1987. http://publications.aston.ac.uk/11876/.
Texto completoTsujimura, Hiroyuki. "Electrochemical nitriding in molten LiCL-KCL-Li3N systems". Kyoto University, 2004. http://hdl.handle.net/2433/147418.
Texto completo0048
新制・課程博士
博士(エネルギー科学)
甲第10972号
エネ博第83号
新制||エネ||24(附属図書館)
UT51-2004-G819
京都大学大学院エネルギー科学研究科エネルギー基礎科学専攻
(主査)教授 伊藤 靖彦, 教授 八尾 健, 教授 吉田 起國
学位規則第4条第1項該当
Wei, Yingying. "Simulation, optimization and development of thermo-chemical diffusion processes". Digital WPI, 2013. https://digitalcommons.wpi.edu/etd-dissertations/145.
Texto completoParascandola, S. "Nitrogen transport during ion nitriding of austenitic stainless steel". Forschungszentrum Dresden, 2010. http://nbn-resolving.de/urn:nbn:de:bsz:d120-qucosa-29591.
Texto completoHubbard, Paul y paul hubbard@rmit edu au. "Characterisation of a Commercial Active Screen Plasma Nitriding System". RMIT University. Applied Physics, 2008. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20090212.161932.
Texto completoParascandola, S. "Nitrogen transport during ion nitriding of austenitic stainless steel". Forschungszentrum Rossendorf, 2001. https://hzdr.qucosa.de/id/qucosa%3A21786.
Texto completoSingh, Omveer. "Investigations of plasma and low energy ion beam nitriding". Thesis, IIT Delhi, 2016. http://localhost:8080/xmlui/handle/12345678/7215.
Texto completoColetta, Marcus Alberto Della. "Comparação do desempenho à abrasão dos aços AISI 4340, 4140, 5140 e 300M nitretados por plasma em diferentes condições". Universidade de São Paulo, 2000. http://www.teses.usp.br/teses/disponiveis/88/88131/tde-14092016-120013/.
Texto completoThe ultrahigh-strength steels with medium carbon and low alloy, like AISI 4340, show excellent tensile strength and fatigue properties further higher hardenability. However, these steels have the phenomenon of tempering embrittlement, that restrict the temperature of treatments after quench or surfaces treatments. The 300M steel was developed aiming the enlargement this area of application, this steel permits treatments in temperatures about 350°C what allowed to use the plasma nitriding without problems with the embrittlement. In this production were compared the properties of the nitrited layers of the 300M nitriding by plasma in 350°C and 550°C with the steels AISI 4340, AISI 4140, AISI 5140 nitriding in 550°C. Plasma nitriding conditions like time and pulse frequency were varied. It was checked that the plasma nitriding showed good performance to improve the resistance to the abrasive wear in ali the steels tested. The 300M steel nitrited in 350°C showed results similar to the others in the pin-on-disk test and the better result occurred to the 300M steel nitrited in 550°C in dC plasma during 6 hours, because of a duble compound lawyer that arouse with a high thickness and high hardness.
Hosmani, Santosh S. "Nitriding of iron-based alloys : the role of excess nitrogen". Stuttgart Max-Planck-Inst. für Metallforschung, 2006. http://nbn-resolving.de/urn:nbn:de:bsz:93-opus-27675.
Texto completoCleugh, Damien. "Effects of rare earth additions on plasma nitriding of En40B steel". Thesis, University of Birmingham, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.289443.
Texto completoVives, Díaz Nicolás. "Nitriding of iron-based alloys residual stresses and internal strain fields /". [S.l. : s.n.], 2007. http://nbn-resolving.de/urn:nbn:de:bsz:93-opus-33995.
Texto completoClauß, Arno Rainer. "Nitriding of Fe-Cr-Al alloys nitride precipitation and phase transformations /". Stuttgart : Max-Planck-Inst. für Metallforschung, 2008. http://d-nb.info/995395918/34.
Texto completoWang, Xiaolan. "Activated atmosphere case hardening of steels". Digital WPI, 2011. https://digitalcommons.wpi.edu/etd-dissertations/413.
Texto completoSchwarz, Benjamin [Verfasser] y Eric Jan [Akademischer Betreuer] Mittemeijer. "Gas nitriding of iron-based alloys / Benjamin Schwarz. Betreuer: Eric Jan Mittemeijer". Stuttgart : Universitätsbibliothek der Universität Stuttgart, 2014. http://d-nb.info/1063335108/34.
Texto completoKirby, A. W. "The reduction of iron content in ferrochromium via the nitriding/leaching route". Thesis, University of Cambridge, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.377841.
Texto completoWu, Dandan. "Low-Temperature Gas-Phase Nitriding and Nitrocarburizing of 316L Austenitic Stainless Steel". Case Western Reserve University School of Graduate Studies / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=case1346900583.
Texto completoSoib, Bin Selamat Mohmad. "Laser surface processing of Ti-6Al-4V alloy". Thesis, University of Strathclyde, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.366777.
Texto completoHan, Meng. "Laser nitriding of metals Influences of the ambient pressure and the pulse duration /". [S.l. : s.n.], 2001. http://webdoc.sub.gwdg.de/diss/2002/han/han.pdf.
Texto completoZhou, Haipo. "Modification of non-metallic inclusions to improve the fatigue properties of nitriding steels". Thesis, University of Canterbury. Mechanical Engineering, 1993. http://hdl.handle.net/10092/6768.
Texto completoWang, Danqi. "LOW-TEMPERATURE GAS-PHASE CARBURIZING AND NITRIDING OF 17-7 PH STAINLESS STEEL". Case Western Reserve University School of Graduate Studies / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=case1386165240.
Texto completoZhecheva, A. Y. "Experimental study and modelling of the process of surface gas nitriding of titanium alloys". Thesis, Queen's University Belfast, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.426922.
Texto completoKaklamani, Georgia. "The effect of active screen plasma nitriding on the cellular compatibility of polmeric biomaterials". Thesis, University of Birmingham, 2012. http://etheses.bham.ac.uk//id/eprint/3844/.
Texto completoНосонова, Любов В`ячеславівна, Любовь Вячеславовна Носонова, Liubov Viacheslavivna Nosonova y О. О. Пушкар. "Вплив процесу антикорозійного азотування на властивості валу насоса типу ЦНСс із сталі 38Х2МЮА". Thesis, Вид-во СумДУ, 2010. http://essuir.sumdu.edu.ua/handle/123456789/6426.
Texto completoFonović, Matej Verfasser] y Eric J. [Akademischer Betreuer] [Mittemeijer. "Nitriding behavior of Ni and Ni-based binary alloys / Matej Fonović. Betreuer: Eric J. Mittemeijer". Stuttgart : Universitätsbibliothek der Universität Stuttgart, 2015. http://d-nb.info/1069107247/34.
Texto completoДоненко, В. А. "Дослідження процесу іонного азотування в імпульсному тліючому розряді". Thesis, Чернігів, 2020. http://ir.stu.cn.ua/123456789/21033.
Texto completoМагістерська робота складається з чотирьох розділів. У першій частині, теоретичній, розглянуті питання пов’язані з фізичними основами процесу іонного азотування, його переваги та недоліки, основні режими азотування деяких металів, дефекти азотування та їх запобігання. У другій частині роботи розглянуто обладнання на якому проводилися досліди, наведено його технічні характеристики. Розглянуто матеріал, що було обрано для дослідів. Розглянуто процес виготовлення зразків матеріалу, розроблена методика вимірювань контрольних зразків. У третій, експериментальній, частині роботи були приведені результати дослідів та режими азотування на яких проводився процес. Наведено фотознімки поверхневої структури зразків, числові значення твердості на різних режимах азотування, досліджено вплив параметрів режиму азотування на мікротвердість та мікроструктуру зразків. У четвертій частині роботи було розглянуто питання охорони праці на робочому місці оператора дифузійної вакуумної установки, проаналізовано основні небезпечні фактори та складено карту умов праці.
The master's dissertation consists of four parts. In the first part, theoretical, the issues are related to the physical basis of the ionic nitriding process, its advantages and disadvantages, the main modes of nitriding of some metals, nitriding defects and their prevention. In the second part of the work the equipment on which experiments were carried out is considered, its technical characteristics are resulted. The material selected for experiments is considered. The process of making material samples is considered, the method of measuring control samples is developed. In the third, experimental, part of the work, the results of experiments and nitriding modes on which the process was carried out were presented. Photographs of the surface structure of the samples, numerical values of hardness at different nitriding modes, the influence of the parameters of the nitriding mode on the microhardness and microstructure of the samples are investigated. In the fourth part of the work, the issue of labor protection at the workplace of the operator of the diffusion vacuum unit was considered, the main dangerous factors were analyzed and a map of working conditions was made.
Kraszczuk, André. "Caracterização microestrutural, mecânica e tribológica de um aço AISI 440B após os tratamentos de têmpera e nitretação a plasma". Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/3/3133/tde-06122017-081003/.
Texto completoIn tribosystems to control friction and wear is necessary. Several solutions have been developed over the last few years, such as heat treatments, thermo-chemical treatments, thin films deposition and duplex coatings. The purpose of the present work is to understand how the microstructure, mechanical and tribological properties of AISI 440B vary after being subjected to the following treatments i) quenching, ii) plasma nitriding. The approach to study AISI 440B microstructure consisted of XRD (X-Ray Diffraction), optical microscopy and SEM (Scanning electron microscopy). The approach to study AISI 440B mechanical properties consisted of Rockwell C hardness and Vickers microhardness. Finally, the approach to study AISI 440B tribological performance was: a) surface and roughness observations through contact rugosimetry and AFM, b) friction coefficient vs. time curves through unlubricated reciprocating tribological test (ASTM G133-05), c) disc and sphere mass loss, d) wear track and wear cap observations through SEM-FEG/EDS, e) surface profile and wear track depth through optical interferomety. The nitrided layer presented tempered martensite as well as ?, ? and CrN nitrides. The maximum surface hardness was 1340 HV 0,1 and a case depth of ~100 µm was found. Regarding the wear mechanisms, in the \"dry sliding of AISI 52100 sphere against as-quenched AISI 440B discs\" tribosystem, the wear mechanisms acting in the body were: severe wear with i) severe plastic deformation, ii) 3-body abrasion at the ends of the wear tracks, iii) oxidation, and iv) mild delamination (oxide pull-out). Regarding the counterbody, it was found: i) mild abrasion and ii) oxide adhesion. In the \"dry sliding plasma nitrided AISI 440B against AISI 52100 spheres\" tribosystem the body suffered mild wear with i) oxidation and ii) delamination. The counterbody suffered i) strong abrasion and ii) oxide adhesion.
Clauß, Arno Rainer [Verfasser]. "Nitriding of Fe-Cr-Al alloys : nitride precipitation and phase transformations / vorgelegt von Arno Rainer Clauß". Stuttgart : Max-Planck-Inst. für Metallforschung, 2008. http://d-nb.info/995395918/34.
Texto completoVives, Díaz Nicolás [Verfasser]. "Nitriding of iron-based alloys; residual stresses and internal strain fields / vorgelegt von Nicolás Vives Díaz". Stuttgart : Max-Planck-Inst. für Metallforschung, 2007. http://d-nb.info/995388687/34.
Texto completoAmoah, Enoch. "Modification of Chemical Vapor-Deposited Carbon Electrodes with Electrocatalytic Metal Nanoparticles through a Soft Nitriding Technique". Digital Commons @ East Tennessee State University, 2019. https://dc.etsu.edu/etd/3616.
Texto completoSamih, Youssef. "Thermomechanical surface treatments of austenitic stainless steels and their effects on subsequent nitriding during “Duplex” treatments". Thesis, Université de Lorraine, 2014. http://www.theses.fr/2014LORR0100/document.
Texto completoOptimizing the surface microstructure and properties is very important to obtain high performance behaviour. Applying appropriate mechanical and thermochemical treatments has been the prime objective of metallurgists. More recently, and particularly for the stainless steels, the Plasma Nitriding was found to be an efficient technique for enhancing the hardness and wear resistance. However, as the nitriding temperature is about 500 °C, the formation of nitrides on the surface leads to a decrease of the corrosion resistance of these alloys. Recent works have shown that using a mechanical pre-treatment allows to decrease the treatment temperature and duration, and also to enhance the nitrogen diffusion within the stainless steels surfaces. In the present work, performances of different Duplex treatments (mechanical + thermochemical) are studied. The Surface Mechanical Attrition Treatment (SMAT), cold rolling and the High Current Pulsed Electron Beam (HCPEB) are used as surface activators prior to plasma nitriding of stainless steels. Before studying the effect of surface activation on the nitrogen diffusion, the effect of the different SMAT parameters (balls size, balls nature, treatment duration … etc.) on the microstructure is analysed. A new technique based on the notion of Geometrically Necessary Dislocations (GND) is used to depict the thickness of the different SMAT-induced layers and compare the effect of the processing parameters. Then, comparative analysis of the results obtained after nitriding of mechanically deformed samples leads to quantify the effect of the different Duplex treatments. X-Ray Diffraction, Secondary Electron Microscopy associated with Electron BackScattered Diffraction (EBSD), hardness measurement and chemical composition analysis by Glow Discharge Optical Emission Spectroscopy (GD-OES) showed the importance of the surface microstructure and deformation state on the nitrogen diffusion
Menezes, Caren Machado. "Contribuições do fenômeno de atrito no sistema ferro puro nitretado e pós-oxidado". reponame:Repositório Institucional da UCS, 2017. https://repositorio.ucs.br/handle/11338/3320.
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Control and reduction of friction can help in the elaboration of strategies of energy efficiency and in the reduction of carbon dioxide (CO2) emission. Although there are well established phenomenological laws for friction, there is no definition of the relationship of macroscopic / microscopic properties to fundamental and nanoscopic properties. The understanding of these correlations as well the mechanisms of energy dissipation involved in the friction phenomenon can help in a greater control of the coefficient of friction. In this work, the coefficient of friction of oxide systems in the outermost layer of pure iron (99.99%) previously nitrided is investigated aiming to find relationships between the phenomenological laws, mechanical properties and theoretical models involving energy dissipation via phonons. For this purpose, samples were characterized using glow discharge optical emission spectroscopy (GD-OES), X-ray diffraction (XRD), atomic probe tomography (APT), scanning electron microscopy (SEM), transmission scanning electron microscopy (STEM), nanoindentation and unidirectional sliding. In the experimental characterization, a gradual reduction of the coefficient of friction was observed, which was accompanied by an increase of the surface oxide content. Despite this, the same trend was not observed in the evolution of the mechanical properties. Therefore, the theoretical calculations based on the mechanisms of phononic dissipation applied to calculate the coefficient of friction well represent the experimental values. In general, the change in the coefficient of friction can be explained by phononic contributions, but the frictional forces of the present system are not totally determined by phononic mechanisms (sic).
Skonieski, Adão Felipe Oliveira. "Influência da mistura gasosa nos processos de nitretação e nitrocarbonetação a plasma do aço AISI 4140". reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2008. http://hdl.handle.net/10183/14369.
Texto completoIn this work various plasma nitriding and plasma nitrocarburizing treatments with hardened and tempered AISI 4140 steel were carried out. The main aim was evaluating the gas mixture influence on metallurgical properties of plasma nitriding and nitrocarburizing layers. For the realization of this study, furnace adaptations and previous experiments in order to verify the parts position influence on final treatments results were necessary. The samples that were nitrided in previous experiments were characterized concerning of compound layer, hardness and chemical composition profiles. All nitride surfaces, were characterized with the parameters: surface hardness, hardness and chemical composition profiles, phases composition on surface, thickness of compound layer, surface toughness, surface roughness and topographical morphology. It was found that thermal parameters are determinants in order to modify the process. Care must be taken about symmetry with this kind of equipment that have no auxiliary heating wall. Later, large variations on microstructural properties in samples under different gas conditions were verified and applications to some cases were proposed.
Kutschmann, Pia, Thomas Lindner, Kristian Börner, Ulrich Reese y Thomas Lampke. "Effect of Adjusted Gas Nitriding Parameters on Microstructure and Wear Resistance of HVOF-Sprayed AISI 316L Coatings". MDPI AG, 2019. https://monarch.qucosa.de/id/qucosa%3A34775.
Texto completoLee, Ming-yen y 李明彥. "A Study of Solid Nitriding". Thesis, 2002. http://ndltd.ncl.edu.tw/handle/26461285490855498843.
Texto completo國立臺灣大學
機械工程學研究所
90
In order to understand the characteristics and parameters of solid nitriding, fertilizer contained with CaCN2 and Japan powder were practiced on three different steels: SKD61, SUS304, and S45C. Solid nitriding with different parameters was studied and compared with gas nitriding. In addition, solid and gas nitriding treatments were also implemented on specimens with blind hole. The results are shown as follows: 1. Adequate amount of nitriding powder provides steady nitriding potential, but when over critical amount, it will not lead to better results. 2. It takes more than 12 hours on solid nitriding treatment to get good nitriding effect. 3. Solid nitriding on SKD61 at 520℃ produces high hardness, thick nitriding layer and thin white layer. 4. Higher hardening depth and lower hardness are obtained in solid nitriding with CaCN2; lower hardening depth and higher hardness are obtained in solid nitriding with Japan powder. Moreover, solid nitriding with Japan powder can be practiced on SUS304, while solid nitriding with CaCN2 can’t. 5. Solid nitriding produces less white layer than gas nitriding does at the same treating temperature. 6. Solid nitriding can be practiced on narrow gap, deep blind hole, or local area of specimen, and produces high hardness, thick nitriding layer and similar results on different location. However, gas nitriding is not suitable in the same specimen condition.
Chen, Chih-Chieh y 陳志杰. "A study on Solid Nitriding". Thesis, 2006. http://ndltd.ncl.edu.tw/handle/73948699002951691058.
Texto completo國立臺灣大學
機械工程學研究所
94
In order to understand the characteristics of solid nitriding, and the feasibility of method applied to steels such as SUS304, JAC1 and SACM645, we heated steel samples in the nitriding powder of a given amounts. The powder would generate active nitrogen that permeated into the steel surface. The purpose of the article was to study the influences of nitriding temperature, nitriding time and composition of the steel on the nitriding depth, the distribution of hardness, the microstructure, and the corrosion-resistance to hot aluminum liquid of the nitriding layer. In addition, the effect of solid nitriding was compared with Gas nitriding. The results were summarized as follows: 1.The solid nitriding could be performed with steels of SUS304, JAC1 and SACM645. SUS304 was the best, JAC1 was the second and SACM645 was the third on the hardening effect of nitriding. 2.The best surface hardness and hardened depth could be obtained for the nitriding time of 12 ~ 15 hours. The surface hardness and hardened depth would not increase significantly for the nitriding time over 15 hours. 3.SUS304 could be nitrided by the nitriding powder at 450℃. Because the low nitriding temperature was not easy to produce white layer and deformation, this method could be applied to the precision machine parts. However, it took more time to get an obvious nitriding layer. 4.In order to gain an effective surface hardness and thick hardening depth, the temperature range from 500℃ to 550℃ was the optimal temperature for the solid nitriding. 5.Steel after solid nitriding could have better corrosion resistance to aluminum liquid. Besides, the corrosion resistance was the best for the steel nitrided at 550℃. 6.The complicated workpiece performed solid nitriding could obtain a more uniform hardening layer than traditional gas nitriding. 7.The solid nitriding was inferior to the traditional gas nitriding on hardening effect, but the solid nitrided layer had better toughness. This feature could improve the brittleness of the gas nitrided layer. Keywords: Solid nitriding, Gas nitriding, Corrosion-resistance test
CHEN, TING-WEI y 陳庭煒. "Laser Nitriding and Heat Treatment of Titanium Alloy". Thesis, 2017. http://ndltd.ncl.edu.tw/handle/66809349166618547374.
Texto completo國立雲林科技大學
機械工程系
105
Heat treatment is always an indispensable process in the production. In recent years, non-traditional heat treatment process has gradually replaced the traditional heat treatment process, features not only steady quality but also saving time. Laser has a good direction and high energy density, with the short heating time of materials, resulting in small thermal deformation, and also can be used in the specific area of treatment. For example, treatment of a hand tool edge. In this research, the laser is applied to the surface of the titanium alloy for heat treatment. The optical fiber laser is projected on the metal surface by a defocused and focused manner, and the heated surface is reorganized to facilitate alloying. With laser nitriding, the nitriding layer is formed to improve the wear resistance and corrosion resistance of titanium alloy. In addition, adding ultrasound for the material surface modification, and observing the material structure by different laser rates and frequency. According to the result, with the atmospheric environment, Ti-6Al-6V-2Sn gets a clear heat-affected zone after lasering, but it has no phase-change by the defocused manner. With the atmospheric environment and the focused manner, Ti-6Al-6V-2Sn gets some vertical holes under the surface after lasering with 1mm/s of scanning rate and 50kHz of frequency, it gains HV 587±50 of hardness after lasering from the cross-sectional of Ti-6Al-4V with CW mode and 10mm/s of scanning rate. With the nitriding environment and the focused manner, it gains HV 780±50 of hardness and thickness 50μm of nitriding layer after lasering from the cross-sectional of Ti-6Al-4V with CW mode and 10mm/s of scanning rate. With the atmospheric environment and the focused manner, it makes irregular cracks on the surface of Ti-6Al-4V while adding the ultrasound in the heat treatment. The result shows that the laser nitriding can gain the dense and thin nitriding layer, it can be applied to processes such as 3C products or medical equipment, and to improve service life.
CHEN, TING-WEI y 陳庭煒. "Laser Nitriding and Heat Treatment of Titanium Alloy". Thesis, 2018. http://ndltd.ncl.edu.tw/handle/r4mdy7.
Texto completo國立雲林科技大學
機械工程系
106
Heat treatment is always an indispensable process in the production. In recent years, non-traditional heat treatment process has gradually replaced the traditional heat treatment process, features not only steady quality but also saving time. Laser has a good direction and high energy density, with the short heating time of materials, resulting in small thermal deformation, and also can be used in the specific area of treatment. For example, treatment of a hand tool edge. In this research, the laser is applied to the surface of the titanium alloy for heat treatment. The optical fiber laser is projected on the metal surface by a defocused and focused manner, and the heated surface is reorganized to facilitate alloying. With laser nitriding, the nitriding layer is formed to improve the wear resistance and corrosion resistance of titanium alloy. In addition, adding ultrasound for the material surface modification, and observing the material structure by different laser rates and frequency. According to the result, with the atmospheric environment, Ti-6Al-6V-2Sn gets a clear heat-affected zone after lasering, but it has no phase-change by the defocused manner. With the atmospheric environment and the focused manner, Ti-6Al-6V-2Sn gets some vertical holes under the surface after lasering with 1mm/s of scanning rate and 50kHz of frequency, it gains HV 587±50 of hardness after lasering from the cross-sectional of Ti-6Al-4V with CW mode and 10mm/s of scanning rate. With the nitriding environment and the focused manner, it gains HV 780±50 of hardness and thickness 50μm of nitriding layer after lasering from the cross-sectional of Ti-6Al-4V with CW mode and 10mm/s of scanning rate. With the atmospheric environment and the focused manner, it makes irregular cracks on the surface of Ti-6Al-4V while adding the ultrasound in the heat treatment. The result shows that the laser nitriding can gain the dense and thin nitriding layer, it can be applied to processes such as 3C products or medical equipment, and to improve service life.
Pao, Wen Lon y 包文龍. "Ion Nitriding /CAPD Composite CrN hard Coating of SKH51". Thesis, 1993. http://ndltd.ncl.edu.tw/handle/52270566959263814873.
Texto completo大同工學院
材料科學(工程)研究所
81
In order to improve wear property of high speed steel SKH51, a combined ion nitriding-cathodic arc plasma deposition (CAPD) processing was studied. Ion Nitriding was performed under care- fully controlled conditions and then a CrN hard coating was de- posited on top of the nitrided surface by CAPD- physical vapor deposition(PVD) method. OM、SEM、EPMA、SAM、XRD and Microhardness tests were carried out to evaluate the characteristics of the combined layers. The thickness of CrN film was measured by kalotest. Rockwell inden- tation analysis was used to qualitatively determine the adhesion of CrN films. Unlubricated friction and wear behaviors of the combined hard-layers against several materials were also invest- igated. The bending strength and deflection toughness of the steel so treated was evaluated by three- point-end test. The results indicated that the combined hard- coating tech- nology effectively increased the surface hardness of SKH51 high speed steel and improved the adhesion of the top CrN hard film to the substrate. Although ion nitriding alone seemed to de- crease the deflection toughness of the material,however,combined layers improved such property. It also exhibited good resistance to wear and low friction coefficient in sliding contact against 304 stainless steel and copper alloy at relatively high loads.
HU, JIA-RONG y 胡家榮. "Plasma nitriding effects on fatigue properties of aerospace material". Thesis, 1991. http://ndltd.ncl.edu.tw/handle/89268696507111956198.
Texto completoHSIEH, FU HSUAN y 謝富軒. "Research of High Temperature Gas Nitriding of 410 Stainless Steel". Thesis, 2001. http://ndltd.ncl.edu.tw/handle/22794540660934423995.
Texto completo國立臺灣大學
機械工程學研究所
89
In order to understand the behavior of 410 stainless steel under gas nitriding at high temperature. We divided the experiment into three parts in the research: 1.High temperature gas nitriding: Steel samples were heated over A1 transformation temperature. We can discuss the influence of nitriding rate; hardness, distribution and microstructure of 410 stainless steel were investigated from the change of nitriding time, the nitriding temperature, ammonia flow-rate, and the nitriding pressure. 2.High temperature two-stage gas nitriding: After gas nitriding at high temperature, steel samples were treated in traditional gas nitriding at lower temperature. We expect that we can find the best hardness distribution of 410 stainless steel, and apply the result of the research to tapping screws. 3. The comparison of high temperature two stage gas nitriding to traditional gas nitriding: From the hardness distribution view, we analyze this two stage nitriding methods. The results were summarized as followed: 1.After the samples of 410 stainless steel are nitriding at high temperature, the hardness of surface layer becomes softer, because of forming α-Fe phase; the core of the samples can be harden, because of forming martensite structure. 2.After high temperature two-stage gas nitriding, the surface layer hardness distribution of 410 stainless steel is approximately satisfying the requirement of tapping screws. 3.After traditional gas nitriding, the proportion of alloy in 410 stainless steel is high, still can result in the depth of nitriding is deficiency and hardness gradient is too high even the surface layer hardness of 410 stainless steel is extremely hard.
Huang, Kuo-Chung y 黃國鐘. "Mechanical Properties Evaluation of Nitriding Steel by Small Punch Test". Thesis, 2019. http://ndltd.ncl.edu.tw/handle/b2er48.
Texto completo遠東科技大學
機械工程研究所在職專班
107
The purpose of this study is to investigate the nitriding effect on mechanical properties of alloyed steel after gas nitriding treatment. To compare different nitriding processes, two techniques has been developed, namely indentation microhardness and small punch tests. A correlation has been analyzed to predict the constitutive relation of the test material from these data. The small punch test is instrumented to provide load-displacement data, and these data can be used to determine flow properties of the test material and the measured values were compared with those obtained from Vickers hardness tests. Various properties and strengths of different nitriding layer thicknesses were observed by electron microscopy (SEM) and metallographic microscope (OM) to illustrate the failure mode of the test material. The final result of this series of experiments would be applied to the mechanical industry applications, such as injection molding process.
Liu, Shie-cheng y 劉師誠. "Microwave plasma nitriding of stainless steel surface on the biocompatibility". Thesis, 2010. http://ndltd.ncl.edu.tw/handle/24523704544605064013.
Texto completo龍華科技大學
工程技術研究所
98
Because hypertension often squeeze into the top ten causes of death, resulting in hypertension for many reasons, including its one of the reasons for blood vessel blockages, and treatment for blood clots, there used to block the vascular stent will be implanted into blood vessels expansion to achieve effective manner to improve. 316 stainless steel and nickel-titanium alloy is the most commonly used vascular stent materials, but materials in vivo release of nickel ions, likely to cause harm to human toxicity. This study mainly to lower nickel content of 303 stainless steel with microwave plasma nitriding and the actual temperature of different nitrogen to obtain better mechanical properties of the surface, anti-bacterial effects and blood compatibility properties.
Cheng, Chih-Wei y 鄭至偉. "Improving Wear Resistance of Cold Working Tool Steel by Solid Nitriding". Thesis, 2007. http://ndltd.ncl.edu.tw/handle/51263694242270177534.
Texto completo國立臺灣大學
機械工程學研究所
95
The purpose of this study is to understand the characteristics of solid nitriding. The effect of solid nitriding on the wear resistance of cold working tool steel such as SKD11, SKH51 and DC53 will be discussed in this article. The above steel sample was nitrided at various temperatures for different time. Then, the microstructure, hardness distribution, nitrogen contents and wear resistance of the nitrided layer was examined for each solid nitriding condition. Moreover, above experimental data was compared with those of conventional NH3 gas nitriding. The results were summarized as follows: 1.In order to obtain an effective surface hardness and the more dense compound layer, the temperature ranging from 500℃ to 550℃ was the optimal temperature for the solid nitriding. 2.The compound layer of steel after the solid nitriding was rather dense and not easy to crack or spall off. It is not necessary to remove the layer by grinding before application. 3.The steel has hardening effect as long as the solid nitriding temperature over 480℃. The wear resistance of nitrided layer increases with increasing nitriding temperature or time. The dies and machine parts should be nitrided under appropriate conditions depending on their application reguirement. Besides, the wear resistance of the nitrided layer was the best for the steel nitrided at 550℃. As to the steel nitrided at 600℃, the holes will appear in the compound layer and nitrides will become coarse. Therefore, both the surface hardness and the wear resistance will decrease. 4.The nitriding at low temperature 480℃~500℃ was not easy to produce deformation, so this method could be applied to the precision machine parts. 5.The compound layer of solid nitriding was permeated with not only nitrogen but also carbon. Although the nitrided layer was not as thick as that of the gas nitriding, the compound layer had better toughness and wear resistance.This point was similar to Tufftriding.
Hwang, Horn-Shin y 黃宏欣. "The study of hybrid treatment of ion nitriding and TiN coating". Thesis, 1993. http://ndltd.ncl.edu.tw/handle/60541851090770306974.
Texto completoRodrigues, Diogo Farias Gonçalves Alexandre. "Plasma nitriding of AA2011 alloy and surface characterization by NDT techniques". Master's thesis, 2015. http://hdl.handle.net/10362/16443.
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