Dissertations / Theses on the topic 'Rolling (Metal-work)'
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劉光磊 and Guanglei Liu. "Modelling of cold rolling textures in mild steel." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1998. http://hub.hku.hk/bib/B31237435.
Full textLiu, Guanglei. "Modelling of cold rolling textures in mild steel /." Hong Kong : University of Hong Kong, 1998. http://sunzi.lib.hku.hk/hkuto/record.jsp?B19712790.
Full textRanatunga, Padmasiri Vipul. "Modeling of profile ring rolling with upper bound elemental technique." Ohio : Ohio University, 2002. http://www.ohiolink.edu/etd/view.cgi?ohiou1178730881.
Full textYe, Xing. "Thermal crown development in hot strip mill work rolls and the role of spray cooling." Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/30124.
Full textApplied Science, Faculty of
Materials Engineering, Department of
Graduate
Su, Yea-Yang. "Pitting degradation of H-13 steel rolls in hot copper rolling." Thesis, Georgia Institute of Technology, 1991. http://hdl.handle.net/1853/18952.
Full textLee, Yew-wing. "The effect of cold rolling on the formability of thermoplastics /." [Hong Kong] : University of Hong Kong, 1987. http://sunzi.lib.hku.hk/hkuto/record.jsp?B12334364.
Full textLee, Yew-wing, and 李耀榮. "The effect of cold rolling on the formability of thermoplastics." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1987. http://hub.hku.hk/bib/B31207716.
Full textChen, Yongjin, and 陳永進. "Effects of rolling conditions on texture and microstructure development in [alpha] brass." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2000. http://hub.hku.hk/bib/B31239997.
Full textBasabe, Mancheno Vladimir Vinicio 1968. "Scale formation and descaling in hot rolling of low carbon steel." Thesis, McGill University, 2008. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=115671.
Full textThe phase composition and morphology of scales grown under conditions similar to those of reheating furnaces were analyzed. Low carbon steel was oxidized over the temperature range 1000-1250°C in gas mixtures of O 2-CO2-H2O-N2, O2-H 2O-N2 and O2-CO2-N2. The mole fraction of each phase, wustite (FeO), magnetite (Fe3O 4) and hematite (Fe2O3) was determined by the direct comparison method Two types of scales were observed. The first type was a crystalline scale with an irregular outer surface composed mostly of wustite, and a negligible amount of magnetite. The second type was the classical three-layer scale composed of wustite, magnetite and hematite. In general, the experiments showed that the furnace atmosphere, oxidation time and temperature influence the phase composition of the scales.
Low carbon steel was oxidized in air over the temperature range 600-1200°C for 120 s to approximate the formation of secondary and tertiary scale in hot rolling. The mole fraction of wustite, magnetite and hematite was determined by the direct comparison method The phase composition of the scales changed with temperature and time. During the initial 30 s of oxidation, wustite was the predominant phase in the temperature range 800-1200°C, and as oxidation proceeded, the percentages of magnetite and hematite increased. In addition, the texture of the scales was investigated by orientation imaging microscopy (OIM); it was found that temperature influences the texture of the scales. The experiments indicated that 850°C is the ideal temperature for the finishing mill in order to reduce surface defects and work roll wear.
The adhesion of scales formed in air on low carbon steel in continuous heating and isothermal conditions was investigated with a four-point bending test. The separation (crack) always occurred inside the scale indicating that the strength of the scale is lower than the strength of the scale/steel interface. It was found that scale adhesion is related to scale porosity, blister formation and stresses acting in the scale. A spallation process was observed when cooling from 800°C to room temperature. The microscopic observations revealed that spallation followed route 1 "strong interface and weak oxide."
Low carbon steel was oxidized over the temperature range 1050-1250°C in O2-CO2H2O-N2 gas mixtures in order to study the hydraulic descaling process. The oxidation times were 15-120 min. and the scales were 130-2000 mum thick. The experimental parameters were chosen to approximate scale formation under conditions similar to those of reheating furnaces. In the hydraulic descaling tests, two modes of scale removal were observed. In the first mode, observed in classical three-layer scales that developed an inner porous layer with low or medium porosity, the horizontal undercutting occurred at the boundary of the inner porous layer and dense scale. The second mode was observed in classical three-layer scales that developed an inner porous layer with high porosity and in crystalline scales. In the second mode, the horizontal undercutting occurred at the first plane of large pores relative to the scale/steel interface. In general, the experiments showed that scale morphology controlled the removability of scale.
Freyer, Burkhard Heinrich. "Gauge and tension control during the acceleration phase of a steckel hot rolling mill." Diss., University of Pretoria, 2002. http://hdl.handle.net/2263/24580.
Full textDissertation (M Eng (Electronic Engineering))--University of Pretoria, 2002.
Electrical, Electronic and Computer Engineering
MEng
unrestricted
Duggirala, Ravikiran. "Computer simulation of ring rolling and FEM analysis of rolling processes." Ohio : Ohio University, 1985. http://www.ohiolink.edu/etd/view.cgi?ohiou1184000912.
Full textLi, Hongchun. "A study on wear and surface roughness of work roll in cold rolling." School of Mechanical, Materials and Mechatronic Engineering - Faculty of Engineering, 2008. http://ro.uow.edu.au/theses/125.
Full textRamasamy, Santhirasegaran. "Analysis of rolling." Ohio : Ohio University, 1988. http://www.ohiolink.edu/etd/view.cgi?ohiou1182868980.
Full textKennedy, Kevin Francis. "A method for metal deformation and stress analysis in rolling." Connect to resource, 1986. http://rave.ohiolink.edu/etdc/view.cgi?acc%5Fnum=osu1261418472.
Full textBiswas, Souvik. "Simulation of thermo-mechanical deformation in high speed rolling of long steel products." Link to electronic thesis, 2003. http://www.wpi.edu/Pubs/ETD/Available/etd-1027103-203032/.
Full textKeywords: product geometry; hot rolling; high speed rolling; rolling simulation; bar and rod rolling; free surface; finite element analysis. Includes bibliographical references (p. 69-75).
Tang, Jianning. "A study of oxide scale deformation and surface roughness transformation in hot strip rolling." Access electronically, 2006. http://www.library.uow.edu.au/adt-NWU/public/adt-NWU20061204.162042/index.html.
Full textGóz, Antonio Vassalo Sales. "Estudo comparativo das propriedades mecânicas dos tubos quadrados laminados a quente com os conformados a frio com tratamento térmico de alívio de tensão /." Guaratinguetá, 2018. http://hdl.handle.net/11449/180724.
Full textBanca: Antonio Jorge Abdalla
Banca: Rafael Humberto Mota de Siqueira
Resumo: O uso de perfis tubulares estruturais, sejam eles de seção circular, quadrada ou retangular, na construção civil ou em equipamentos mecânicos ainda é incipiente no Brasil. Isto se deve, entre outros fatores, ao baixo número de pesquisas nacionais sobre o tema. Para contribuir neste campo, este trabalho teve o objetivo de realizar um estudo comparativo entre seções quadradas laminadas a quente com as conformadas a frio, pois, no Brasil, a maior parte dos tubos são fabricados por conformação a frio e também por haver grande interesse internacional pela comparação direta entre os perfis produzidos por estes dois processos distintos. Para isto, análises dimensionais da seção transversal, das composições químicas e metalográficas e ensaios de dureza por microindentação, de impacto Charpy, de tração e de compressão foram realizados em tubos de 80x80x10 mm de aço carbono para aplicação estrutural com tensão de escoamento mínima de 355 MPa. Os resultados demonstraram que o tubo conformado a frio com posterior tratamento térmico de alívio de tensão possui área de seção transversal 2,7% menor, distribuição de dureza e propriedades mecânicas praticamente uniformes na seção transversal, ótima tenacidade em baixas temperaturas e maior resistência à tração e à compressão quando comparado com a mesma seção laminada a quente. Portanto, para a seção analisada, ficou comprovada a equivalência estrutural dos tubos laminados a quente com os conformados a frio com posterior alívio de tensão por t... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The use of hollow structural sections, be them circular, square or rectangular hollow section, at civil construction or at mechanical equipment is still incipient in Brazil. This is due, among other factors, the low number of national researches about the matter. To contribute in this field, this work had the goal to realize a comparative study between square hollow sections hot rolled with the cold formed because most tubes are produced by cold forming in Brazil and also because the great international interesting for the direct comparison between the profiles produced by these two different processes. For this, cross section dimension, chemical composition and metallographic analyzes and microindentation hardness, Charpy impact, tension and compression tests were realized in tubes of 80x80x10 mm of carbon steel for structural application with minimum yield stress of 355 MPa. The results demonstrated that the cold formed tube with subsequent heat treatment of stress relieve has cross sectional area 2,7% lower, uniform hardness distribution and mechanical properties in the cross section, great toughness at low temperatures and higher tension and compression resistance when compared with the same section hot rolled. Therefore, for the section analyzed, was proved the structural equivalence of the hot rolled tubes with the cold formed plus stress relieve by heat treatment.
Mestre
Joshi, Alhad A. "Development of an integrated package for the analysis of hot and cold rolling of strips and sheets." Ohio : Ohio University, 1989. http://www.ohiolink.edu/etd/view.cgi?ohiou1187038990.
Full textBanga, Rajneesh. "Virtual Material Processing (VMP) on the World Wide Web (WWW) cold rolling." Ohio : Ohio University, 2000. http://www.ohiolink.edu/etd/view.cgi?ohiou1171384548.
Full textDewasurendra, Lohitha. "A finite element method for ring rolling processes." Ohio : Ohio University, 1998. http://www.ohiolink.edu/etd/view.cgi?ohiou1175098096.
Full textShramko, John P. "Experimental determination of the microstructural evolution of Inconel X-750 during cold rolling." Ohio : Ohio University, 1994. http://www.ohiolink.edu/etd/view.cgi?ohiou1180039435.
Full textBurge, David Henry. "Experimental validation of roll force and profile fill for a profile ring rolling computer model." Ohio : Ohio University, 1996. http://www.ohiolink.edu/etd/view.cgi?ohiou1178657382.
Full textJudice, Gustavo Henrique. "Análise numérica da propagação de defeitos internos na laminação transversal com cunha." [s.n.], 2012. http://repositorio.unicamp.br/jspui/handle/REPOSIP/264489.
Full textDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica
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Resumo: O processo de conformação denominado Laminação Transversal com Cunha, industrialmente conhecido como Cross Wedge Rolling (CWR), tem se destacado na indústria pela sua flexibilidade, produtividade e economia de material, porém pode apresentar defeitos internos que, em alguns casos, inviabiliza a utilização dos produtos. É um defeito de difícil avaliação quanto a sua formação e propagação e ainda não se desenvolveu um mapa de processamento que represente de forma precisa e consistente as condições em que o defeito pode aparecer. Este estudo apresenta resultados dos campos de deformação plástica, tensão, temperatura e do aspecto do desenvolvimento de defeitos internos, acrescentados ao tarugo, através de simulações do processo de laminação transversal com cunha. O estudo se desenvolveu na criação de modelos de elementos finitos pelo software comercial Abaqus® versão 6.9-2, que seguiram condições geométricas de um processo real. Inicialmente, modelos bidimensionais foram simulados apresentando diferentes densidades de malha. Posteriormente, modelos com um vazio central foram simulados e confirmou-se a boa correlação de seus resultados com os encontrados na literatura. Na sequência, um modelo com propriedades de porosidade indicou que a região central do tarugo apresentou a maior densidade de vazios. Também foram simulados modelos com vazios e inclusões de diferentes tamanhos, disposições e formas, com destaque para a região em volta das inclusões, por apresentar a formação de vazios. Por último, foram simulados dois modelos tridimensionais, um apresentando um vazio interno no centro do tarugo, que apresentou os campos de tensão, de deformação plástica e de temperatura parecidos com o do modelo bidimensional correspondente, porém com valores maiores. O outro modelo tridimensional apresentou propriedades de porosidade e indicou que a maior probabilidade de formação de defeitos se concentrou na extensão longitudinal central do tarugo. Os maiores níveis de temperatura, deformação plástica e tensão foram presentes na região central do tarugo, tanto nos modelos bidimensionais quanto nos tridimensionais, indicando que essa região apresentou os maiores níveis de solicitação, o que pode favorecer o surgimento dos defeitos internos
Abstract: Cross Wedge Rolling is a metal forming process which has become very important in the industry for its flexibility, productivity and material savings, although presenting the critical problem of internal defects generation which restricts the use of rolled products, since it is very difficult to asset the defects formation and propagation and it was still not found a processing map to represent CWR with precise and consistent conditions with which the defect should or should not appear. In this study some numerical results are presented in terms of plastic strain, stress, temperature and the development of internal defects within the billet. These results were obtained with different finite element models developed with the commercial software Abaqus Version 6.9-2 by simulating materials with different internal characteristics, representing geometric conditions identified in the actual process. Initially two-dimensional models were simulated with different mesh densities; then, models with a central void were simulated and a good relationship was found with the results found in the literature. Then a model was simulated to characterize the porosity of the material, and was verified that the porosity is concentrated at the center of billet. Other models were also simulated with voids and inclusions of different sizes, distributions and shapes which were added manually. These models showed similar results, and the models with inclusions developed voids within the metallic matrix. Finally, two models (three-dimensional) were simulated, one with an internal void in the center of the billet, which showed the development of stress fields, plastic deformation and temperature similar to that corresponding two-dimensional model, but with higher values. The other three-dimensional model, which presented properties of porosity, showed that the highest probability of defect formation focused in the central and longitudinal extent region of the billet. All models showed that the central region of the billet presents the highest levels of temperature, plastic strain and stress probably favoring the initiation of internal defects
Mestrado
Materiais e Processos de Fabricação
Mestre em Engenharia Mecânica
Belinski, Robert A. "An analysis, design, and improvement methodology for shape rolling processes and procedures for the compensation of dies." Ohio : Ohio University, 1999. http://www.ohiolink.edu/etd/view.cgi?ohiou1175264501.
Full textJi, Meixing. "FEM based interdisciplinary approaches to optimization of multi-stage metal forming processes." Columbus, Ohio : Ohio State University, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1158674599.
Full textAnbajagane, Rathinavel. "An upper bound method of solution for the pack rolling process and software integration of PACK 1.5." Ohio University / OhioLINK, 1993. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1174933594.
Full textFischer, Christian E. "Development of a practical software tool for the design of rolls for near net shape profile rolling." Ohio : Ohio University, 1994. http://www.ohiolink.edu/etd/view.cgi?ohiou1176922884.
Full textShen, Kai, and 沈凱. "A transmission electron microscopy study of the development of rollingdeformation microstructures in an interstitial free steel." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2004. http://hub.hku.hk/bib/B31245894.
Full textOsio, Ignacio G. "Optimization of shape rolling processes using finite element analysis and experimental design methodology." Ohio : Ohio University, 1992. http://www.ohiolink.edu/etd/view.cgi?ohiou1172866385.
Full textCalçada, Maurício Vieira. "Avaliação Mecânica e Microestrutural da liga de alumínio AA3104 empregada na indústria de fabricação de latas laminada à frio com e sem interpasses." Universidade Estadual Paulista (UNESP), 2018. http://hdl.handle.net/11449/153489.
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Os fabricantes de latas vêm se tornando cada vez mais exigentes na qualidade e propriedades dos materiais utilizados na confecção de seus produtos. Um dos metais mais usados na indústria de manufatura de componentes obtidos através de estampagem e estiramento, como na fabricação de corpo de latas de bebidas, trata-se da liga de Alumínio AA3104. Isto se deve às suas propriedades mecânicas, estampabilidade, entre outra. Ela pertence ao grupo 3XXX, sendo que seu principal elemento de liga é o manganês (em pequenas quantidades / teores). Trata-se de uma liga não tratável termicamente, sendo que suas propriedades mecânicas são melhoradas a partir da formação de solução sólida e / ou deformação à frio. Desta forma, o presente estudo teve como objetivo avaliar de maneira detalhada a influência de duas diferentes condições de laminação à frio sobre o comportamento mecânico e microestrutural da liga de Alumínio AA3104: laminação à frio com tempo de resfriamento intermediário e sem tempo de resfriamento intermediário entre passes. A análise mecânica, por meio do Ensaio de Tração, mostrou que os materiais laminados com tempo de resfriamento intermediário obtiveram maiores valores de Limite de Escoamento (283,1 MPa) e Limite de Resistência a Tração (309,3 MPa) do que aqueles materiais laminados sem este tempo de resfriamento intermediário (273,2 e 300,0 MPa, respectivamente). Isto foi justificado pelo aumento da quantidade de partículas de segunda fase precipitados na matriz da liga, que dificultou a movimentação de discordâncias, tornando o material mais resistente.
The manufacturers of cans have become increasingly demanding in quality and in the properties of the materials used to make their products. One of the most used metals in the manufacturing industry of components obtained by stamping, as in the manufacture of beverage cans body, is the AA3104 Alloy. This is due to its mechanical properties, stampatability, among others. It belongs to the 3XXX group, and its main alloying element is manganese (in small amounts / contents). It is an alloy not thermally treatable, where its mechanical properties are improved from the formation of solid solution and / or cold forming. Therefore, the present study had as objective to evaluate in detail the influence of two different conditions of cold rolling on the mechanical and microstructural behavior of the aluminum alloy AA3104: cold rolling with intermediate cooling time and without intermediate cooling time between passes. The mechanical analysis, through the Tensile Test, showed that rolled materials with intermediate cooling time obtained higher values of Yield Strength (283,1 MPa) and Ultimate Tensile Strength (309,3 MPa) than those laminated materials without this intermediate cooling time (273,2 and 300,0 MPa, respectively). This was justified by the increase in the amount of second phase particles and precipitated dispersions in the alloy matrix, which made difficult the movement of dislocations, making the material more resistant
Pereira, Marcelo dos Santos. "Influencia do processamento termomecanico na estrutura e nas propriedades mecanicas de um aço ultra-baixo carbono livre de intersticiais." [s.n.], 1998. http://repositorio.unicamp.br/jspui/handle/REPOSIP/263085.
Full textTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica
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Resumo: Nos últimos anos, melhorias substanciais na tecnologia de fabricação de aços tornaram possível o desenvolvimento de aços de ultra-baixo carbono livres de intersticiais (interstitial free steels). Os aços IF apresentam teores de carbono menores que 50ppm, em peso, e são estabilizados com titânio e/ou nióbio, objetivando remover os elementos intersticiais presentes, principalmente o carbono e o nitrogênio. Se caracterizam por apresentar altos valores no coeficiente de anisotropia médio e no alongamento, e são aplicados em operações que requerem materiais com alta capacidade de conformação. O principal objetivo deste trabalho é o de estabelecer uma correlação entre parâmetros do tratamento termomecânico; em especial as temperaturas de acabamento e bobinamento; a microestrutura e as propriedades mecânicas e, com isso, propor uma otimização no processamento deste material. O aço, doado pela Açominas, foi laminado a quente e a frio e recozido continuamente em escala laboratorial. As propriedades mecânicas foram determinadas através de ensaios de tração e de embutimento e ensaios para determinação do coeficiente de anisotropia médio, enquanto a microestrutura foi caracterizada através de microscopia óptica e eletrônica de varredura. Os resultados mostraram que a aplicação de altas temperaturas de acabamento (900°C) e de bobinamento (700°C), durante a laminação a quente, ocasiona a formação de uma microestrutura fina, homogênea e equiaxial, provoca um crescimento no tamanho dos precipitados e aumenta os valores do coeficiente de anisotropia e do alongamento do material, propiciando uma condição de processamento ótima do aço para aplicações em estampagem extra-profunda
Abstract: In the last years, substantial improvements on steelmaking technology have made possible the development of interstitial-free steels containing ultra-Iow carbonoThe IF steels show carbon content lower than 50 ppm, in weight, and are stabilized with titanium and niobium, in arder to remove the interstitial elements, mainly carbon and nitrogen. They are characterized by high levels of r-values and elongation, and are applied in operations which require materials with high conformation capacity. The purpose of this investigation is to establish correlations among thermomechanical treatment parameters; specially finishing and coiling temperatures; microstructure and mechanical properties and, on establishing these correlations, it proposes a processing optimizing of this material. The steel, produced by Açominas, was hot and cold rolled and continuous annealed in laboratorial scale. The mechanical properties were determined by tensile, drawing and r-value tests, whereas the microstructure was characterized by optical and scanning electron microscopy. The results showed that the use of high finishing temperature (900°C) and high coiling temperature (700°C), during hot rolling, promotes a fine, homogeneous and eqüiaxial microstructure, grows the precipitate and increases the r-values and the elongation, propitiating a steel optimum processing condition for extra deep-drawing applications
Doutorado
Materiais e Processos de Fabricação
Doutor em Engenharia Mecânica
Zanchetta, Bianca Delazari. "Influência da laminação assimétrica nas propriedades mecânicas do alumínio AA 1050." Universidade Federal de São Carlos, 2017. https://repositorio.ufscar.br/handle/ufscar/8998.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Aluminum sheets are produced by rolling followed by annealing. However when submitted to deep drawing earing appears, caused by the plastic anisotropy resulting from the production process. After annealing the main texture is cube {001} , that is recognized as being the cause of this heterogeneity during deep drawing. The literature shows that when shear stress is applied in the deformation process, it leads to texture changes. In this study asymmetric rolling (AR) was used as a technique to produce shear. The shear stress is introduced by the different velocities between the upper and bottom rolls and in this study this was achieved by using roll radius relations (r1/r2) of 1,5 and 2. Rolling reductions of 50% in thickness were applied to aluminum AA1050 sheets. The conventional rolling (CR) was compared to the asymmetric rolling (AR), at two different reduction rates: 5% and 10%. The crystallographic textures were obtained by xray diffraction. Finite element analysis, using the DEFORM software, was used to analyze the effective strain distribution throughout the thickness as well as its components: normal strain, shear strain and rigid body rotation. The samples were annealed in a furnace with 350°C for 05, 10, 15, 20 and 60 minutes. The microstructure was characterized by optical microscopy, electron back scatter diffraction and x-ray diffraction. The plastic anisotropy (Lankford Parameter) was measured by tensile experiments at three different sheet directions and by the Erichsen test. The deformed samples’ microstructure was analyzed at the surface near to the upper roll and at half of the thickness. For the CR the main components were brass (Bs) {011} , Goss (Gs) {011} and copper (Cu) {112} , with 8.8 intensity at the central layer, and 4.5 at the surface. For AR samples the was more random at the surface of the samples with 5% of reduction per pass, added to a component of rotation in the normal direction, what resulted in cube and rotated cube textures or near to these orientations, generating a type of fiber {100}//ND. The maximum intensities for the (r1/r2) of 1,5 and 2 were 3 and 4, respectively. For the samples with 10% of reduction per pass the rolled texture was still presented, with a more intense rotation in the transversal direction related to the rolling direction and shear texture components {100}//ND and . The maximum intensities were 3 and 3.5 , for the (r1/r2) of 1,5 and 2, respectively. In the center layer of the samples with 5% of reduction per pass for (r1/r2) of 1,5 and 2 showed a intensity of 5.26 and 6.56, respectively and the strongest shear texture was rotated Goss (C). (011)[0-1- 1] The samples with 10% reduction per pass showed the greatest reduction of intensity with 3.05 and 3.63, for the (r1/r2) of 1,5 and 2 respectively, and the highest intensity was related to rotate the Goss (011)[0-1-1] component. In the pole figures rotations around the transversal direction (TD) and the normal direction (ND) were observed. Using the finite element analysis the rotation around the TD and ND were quantified and its variation across the thickness were analyzed. The rigid body rotation is superposed to shear , which leads to the observed texture gradients. The rotation around TD is imposed by the velocity difference between top and bottom roll, whereas the ND rotation is imposed by the experimental configuration, which permit variation of the sample alignment at the roll mill entrance. This was stronger for the 5% reduction rate and more concentrated at the samples surface. After 05 minutes the annealed samples were already recrystallized , after 60 minutes the grain average size was 30µm, and hardness 21HV. The annealed texture for the CR sample showed the greatest concentration off Cube texture {001} and intensity of 8.08 times the random. For the AR samples with 5% reduction per pass the intensities for the (r1/r2) of 1,5 and 2 was 5.88 and 6.56, respectively, and for the 10% reduction per pass 2.96 and 2.85, respectively. The AR decreases the annealed texture. In the samples of 5% reduction per pass the most intense shear texture was rotated Goss, the 10% reduction per pass did not have a predominant component. The Lankford parameters showed less anisotropy for the annealed samples with 10% reduction per pass. Based on the values of anisotropy and hardening exponent for each sample, the Limiting Rate of Drawing was calculated. The AR got a superior values than the CR ones, indicating an improvement of the drawability.
Chapas de Alumínio são comumente produzidas por laminação seguida de recozimento. Entretanto, ao serem submetidas à estampagem profunda apresentam problemas de orelhamento, devido à anisotropia plástica. Durante o recozimento a textura predominante é a cubo {001} , esta textura é reconhecida como sendo a causadora da má estampabilidade. A literatura indica que é possível alterar a textura final aplicando cisalhamento durante o processamento do material, neste trabalho aplicamos a Laminação Assimétrica (LA) como forma de produzir cisalhamento sobre a chapa. Utilizando o alumínio AA1050 até atingir um total de 50% de redução em espessura, com relações de assimetria (LA) de (r1/r2) de 1,5 e 2 com 5% e 10% de redução por passe e Laminação Convencional (LC) com taxa de 10% de redução por passe. A deformação experimental foi comparada à simulação de elementos finitos utilizando o software DEFORM, e a distribuição de deformação equivalente foi analisada ao longo da espessura da chapa. As amostras passaram por recozimento em forno tipo MUFLA, a 350°C por 05, 10, 15, 20 e 60 minutos. As amostras deformadas foram caracterizadas por microscopia óptica e sua textura cristalográfica foi obtida por difração de raios-x. As amostras recozidas passaram por caracterização microestrutural por microscopia óptica, difração de elétrons retroespalhados (EBSD) e difração de raios-x. A caracterização mecânica foi feita por ensaios de dureza, de tração e pelo ensaio de embutimento Erichsen. A microestrutura das amostras deformadas foi analisada próxima a superfície do rolo superior e no plano central a espessura. Para a LC foram encontradas concentrações maiores de Bs {011} , Gs {011} , Cu {112} , com intensidade máxima de 8,8 para o centro da chapa e de 4,5 na superfície. Para as amostras LA houve uma maior aleatoriedade das texturas tanto na superfície quanto no plano central. As amostras com 5% de redução por passe apresentaram as melhores reduções de intensidades máximas, somada a uma componente de rotação na direção normal (DN) da chapa, as intensidades máximas para (r1/r2) 1,5 e 2 foram de 3 e 4 respectivamente. Nas amostras de 10% de redução por passe ainda estavam presentes as componentes de laminação com uma rotação mais acentuada ao redor da direção transversal (DT) a direção de laminação as intensidades máximas foram de 3 e 3,5 para (r1/r2) 1,5 e 2 respectivamente. No centro da chapa as amostras de 5% de redução por passe para (r1/r2) 1,5 e 2 apresentam intensidades de 5,26 e 6,56 respectivamente e a textura de cisalhamento mais forte foi a Goss rodado (011) [0 1 1 ] (C). Já as amostras de 10% de redução apresentam as maiores reduções de intensidade com 3,05 e 3,63, para (r1/r2) 1,5 e 2 respectivamente, e uma proporção maior de intensidade Goss rodado (C). A simulação numérica foi utilizada para quantificar as rotações de corpo rígido impostas pela deformação, indicadas nas figuras de pólo pelas rotações ao redor da DN e da DT. Quanto às rotações ao redor da DT, para as reduções de 5% o cisalhamento se concentra na superfície e a rotação de corpo rígido é relativamente mais intensa no centro da amostra; nas reduções de 10% uma contribuição mais intensa tanto da rotação quanto do cisalhamento foi obtida. Quanto à rotação ao redor de DN ela foi mais intensa na superfície da chapa e para a redução de 5%. Após 05 minutos de tratamento as amostras já se encontravam recozidas atingindo um tamanho de grão médio de cerca de 30µm, e dureza em torno de 21HV. A textura de recozimento da amostra LC apresentou maiores concentrações das texturas cubo {001} e intensidade de 8,08. Para a LA com 5% de redução por passe as intensidades são máximas para r1/r2 1,5 e 2 foram 5,88 e 6,56, respectivamente, já para as com 10% de redução por passe, 2,96 e 2,85, respectivamente, apresentando a maior redução de concentração de texturas, assim como no material deformado. A LA promoveu, portanto a redução da intensidade de textura de recozimento Nas amostras de 5% de redução por passe a textura de cisalhamento mais intensa foi a Goss rodado, já para as amostras de 10% não houve uma componente predominante. O ensaio de tração nas três direções apresentou uma menor anisotropia para as amostras recozidas com 10% de redução por passe. Baseado nos valores de anisotropia e encruamento para cada amostra foi calculado a taxa de limite de embutimento, na qual as amostras LA obtiveram um valor superior a LC, indicando possuírem um melhor comportamento ao ensaio.
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