Microestrutura e propriedades mecânicas da liga AA6061 processada por deformação plástica severa em temperatura criogênica
Autor(a) principal: | |
---|---|
Data de Publicação: | 2017 |
Tipo de documento: | Tese |
Idioma: | por |
Título da fonte: | Repositório Institucional da UFSCAR |
Texto Completo: | https://repositorio.ufscar.br/handle/ufscar/9446 |
Resumo: | The present work aimed two fronts: to characterize the mechanical behavior of the AA6061 alloy at cryogenic temperature, and to study the microstructural and properties evolution after cryogenic severe plastic deformation. Samples of AA6061 alloy were solution heat-treated and processed by conventional rolling, asymmetric rolling and equal-channel angular pressing (ECAP), both at room temperature and cryogenic temperature. After processing, such samples were treated for precipitation at 25 °C and at 100 °C, for different times. On the cryogenic mechanical behavior it was observed the suppression of the dynamic strain aging, which also allowed the ECAP processing without cracking. Uniform and total elongation and mechanical strength were always higher at -196 °C than at room temperature. The strain-rate sensitivity, despite having low values, becomes positive for cryogenic deformation, directly affecting the deformation capacity. Regardless of the processing route employed, a saturation of the hardness around 125 HV has been seen. The microstructures after cryogenic ECAP were very refined in relation to the starting material (average grain size up to 500 nm). In addition, it was observed a homogeneous strains distribution after cryogenic processing, with detection of several new fine grains from grain boundaries, which suggests recrystallization. The tensile tests results, after cryogenic processing in combination with artificial aging at 100 °C (48 hours), indicated an increase in uniform elongation. Regarding mechanical strength, the highest values were observed for extrusion at room temperature combined with artificial aging. In addition, there was to some static recovery during artificial aging, especially for cryogenic processing, which generates thermodynamically unstable microstructures. The density of dislocations, in fact, decreases with the prolongation of artificial aging time. Thus, the present study was based on a study of the cryogenic mechanical behavior of the AA6061 alloy, as well as the possibility of processing by cryogenic severe deformation. |
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Magalhães, Danielle Cristina CamiloSordi, Vitor Luizhttp://lattes.cnpq.br/8364164402481940Kliauga, Andrea Madeirahttp://lattes.cnpq.br/3527528295399928http://lattes.cnpq.br/5486724956564584ae3f7e8f-0c98-440a-8034-a11e8ec3336b2018-02-20T12:12:38Z2018-02-20T12:12:38Z2017-08-08MAGALHÃES, Danielle Cristina Camilo. Microestrutura e propriedades mecânicas da liga AA6061 processada por deformação plástica severa em temperatura criogênica. 2017. Tese (Doutorado em Ciência e Engenharia de Materiais) – Universidade Federal de São Carlos, São Carlos, 2017. Disponível em: https://repositorio.ufscar.br/handle/ufscar/9446.https://repositorio.ufscar.br/handle/ufscar/9446The present work aimed two fronts: to characterize the mechanical behavior of the AA6061 alloy at cryogenic temperature, and to study the microstructural and properties evolution after cryogenic severe plastic deformation. Samples of AA6061 alloy were solution heat-treated and processed by conventional rolling, asymmetric rolling and equal-channel angular pressing (ECAP), both at room temperature and cryogenic temperature. After processing, such samples were treated for precipitation at 25 °C and at 100 °C, for different times. On the cryogenic mechanical behavior it was observed the suppression of the dynamic strain aging, which also allowed the ECAP processing without cracking. Uniform and total elongation and mechanical strength were always higher at -196 °C than at room temperature. The strain-rate sensitivity, despite having low values, becomes positive for cryogenic deformation, directly affecting the deformation capacity. Regardless of the processing route employed, a saturation of the hardness around 125 HV has been seen. The microstructures after cryogenic ECAP were very refined in relation to the starting material (average grain size up to 500 nm). In addition, it was observed a homogeneous strains distribution after cryogenic processing, with detection of several new fine grains from grain boundaries, which suggests recrystallization. The tensile tests results, after cryogenic processing in combination with artificial aging at 100 °C (48 hours), indicated an increase in uniform elongation. Regarding mechanical strength, the highest values were observed for extrusion at room temperature combined with artificial aging. In addition, there was to some static recovery during artificial aging, especially for cryogenic processing, which generates thermodynamically unstable microstructures. The density of dislocations, in fact, decreases with the prolongation of artificial aging time. Thus, the present study was based on a study of the cryogenic mechanical behavior of the AA6061 alloy, as well as the possibility of processing by cryogenic severe deformation.A ênfase do presente trabalho deu-se em duas frentes: caracterizar o comportamento mecânico da liga AA6061 em temperatura criogênica, e estudar a evolução microestrutural e de propriedades após deformação plástica severa criogênica. Amostras da liga AA6061 foram solubilizadas e submetidas a processos de laminação convencional, laminação assimétrica e extrusão em canal angular, tanto em temperatura ambiente quanto criogênica. Após os processamentos, tais amostras foram termicamente tratadas para precipitação a 25 ºC e a 100 ºC, por diferentes tempos. Quanto ao comportamento mecânico criogênico, observou-se a supressão da precipitação dinâmica, a qual permitiu também a deformação por extrusão sem trincamento. A resistência mecânica e alongamentos uniforme e total são sempre maiores a -196 ºC do que em temperatura ambiente. A sensibilidade à taxa de deformação, apesar de possuir valores baixos, torna-se positiva para deformação criogênica, impactando diretamente na capacidade de deformação. Independentemente do processamento empregado, observou-se uma saturação das durezas em torno de 125 HV. As microestruturas após extrusão em canal angular criogênica apresentam-se bastante refinadas em relação ao material original, com tamanho médio de grão igual a 500 nm. Adicionalmente, observou-se uma distribuição de deformações mais homogênea no processamento criogênico, verificando-se a presença de grão muito finos, sugerindo recristalização. Os resultados de tração pós-processamento criogênico indicaram um aumento do alongamento uniforme na combinação com o envelhecimento artificial a 100 ºC (48 horas). Quanto à resistência mecânica, os maiores valores foram observados para a extrusão em temperatura ambiente combinada com envelhecimento artificial. Além disso, houve recuperação estática durante o envelhecimento artificial, principalmente para as deformações criogênicas, as quais geram microestruturas termodinamicamente mais instáveis. A densidade de discordâncias, de fato, diminui com o prolongamento do tempo de envelhecimento artificial. Dessa forma, o presente trabalho constituiu-se de um estudo dirigido do comportamento mecânico criogênico da liga AA6061, bem como da possibilidade de processamento por deformação severa criogênica.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)CNPq: 153181/2013-3FAPESP: 2014/15091-7porUniversidade Federal de São CarlosCâmpus São CarlosPrograma de Pós-Graduação em Ciência e Engenharia de Materiais - PPGCEMUFSCarAlumínio AA6061Deformação plástica severa criogênicaComportamento mecânico criogênicoExtrusão em canal angularPrecipitaçãoAluminum AA6061Cryogenic severe plastic deformationCryogenic mechanical behaviorEqual-channel angular pressingAgingENGENHARIAS::ENGENHARIA DE MATERIAIS E METALURGICAMicroestrutura e propriedades mecânicas da liga AA6061 processada por deformação plástica severa em temperatura criogênicainfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/doctoralThesisOnline6006003ecbc8ef-0ebd-4b04-9d94-9ea2a68cf81finfo:eu-repo/semantics/openAccessreponame:Repositório Institucional da UFSCARinstname:Universidade Federal de São Carlos (UFSCAR)instacron:UFSCARORIGINALTeseDCCM.pdfTeseDCCM.pdfapplication/pdf8210400https://repositorio.ufscar.br/bitstream/ufscar/9446/1/TeseDCCM.pdfaa7c4ffb6808f655dbda64d16775bd21MD51LICENSElicense.txtlicense.txttext/plain; charset=utf-81957https://repositorio.ufscar.br/bitstream/ufscar/9446/2/license.txtae0398b6f8b235e40ad82cba6c50031dMD52TEXTTeseDCCM.pdf.txtTeseDCCM.pdf.txtExtracted texttext/plain274156https://repositorio.ufscar.br/bitstream/ufscar/9446/3/TeseDCCM.pdf.txt3795729a6be7dc97cd7aca0a38ea218dMD53THUMBNAILTeseDCCM.pdf.jpgTeseDCCM.pdf.jpgIM Thumbnailimage/jpeg6884https://repositorio.ufscar.br/bitstream/ufscar/9446/4/TeseDCCM.pdf.jpga03bc0d454a5034f7e36bc67d4163127MD54ufscar/94462023-09-18 18:31:12.899oai:repositorio.ufscar.br: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Repositório InstitucionalPUBhttps://repositorio.ufscar.br/oai/requestopendoar:43222023-09-18T18:31:12Repositório Institucional da UFSCAR - Universidade Federal de São Carlos (UFSCAR)false |
dc.title.por.fl_str_mv |
Microestrutura e propriedades mecânicas da liga AA6061 processada por deformação plástica severa em temperatura criogênica |
title |
Microestrutura e propriedades mecânicas da liga AA6061 processada por deformação plástica severa em temperatura criogênica |
spellingShingle |
Microestrutura e propriedades mecânicas da liga AA6061 processada por deformação plástica severa em temperatura criogênica Magalhães, Danielle Cristina Camilo Alumínio AA6061 Deformação plástica severa criogênica Comportamento mecânico criogênico Extrusão em canal angular Precipitação Aluminum AA6061 Cryogenic severe plastic deformation Cryogenic mechanical behavior Equal-channel angular pressing Aging ENGENHARIAS::ENGENHARIA DE MATERIAIS E METALURGICA |
title_short |
Microestrutura e propriedades mecânicas da liga AA6061 processada por deformação plástica severa em temperatura criogênica |
title_full |
Microestrutura e propriedades mecânicas da liga AA6061 processada por deformação plástica severa em temperatura criogênica |
title_fullStr |
Microestrutura e propriedades mecânicas da liga AA6061 processada por deformação plástica severa em temperatura criogênica |
title_full_unstemmed |
Microestrutura e propriedades mecânicas da liga AA6061 processada por deformação plástica severa em temperatura criogênica |
title_sort |
Microestrutura e propriedades mecânicas da liga AA6061 processada por deformação plástica severa em temperatura criogênica |
author |
Magalhães, Danielle Cristina Camilo |
author_facet |
Magalhães, Danielle Cristina Camilo |
author_role |
author |
dc.contributor.authorlattes.por.fl_str_mv |
http://lattes.cnpq.br/5486724956564584 |
dc.contributor.author.fl_str_mv |
Magalhães, Danielle Cristina Camilo |
dc.contributor.advisor1.fl_str_mv |
Sordi, Vitor Luiz |
dc.contributor.advisor1Lattes.fl_str_mv |
http://lattes.cnpq.br/8364164402481940 |
dc.contributor.advisor-co1.fl_str_mv |
Kliauga, Andrea Madeira |
dc.contributor.advisor-co1Lattes.fl_str_mv |
http://lattes.cnpq.br/3527528295399928 |
dc.contributor.authorID.fl_str_mv |
ae3f7e8f-0c98-440a-8034-a11e8ec3336b |
contributor_str_mv |
Sordi, Vitor Luiz Kliauga, Andrea Madeira |
dc.subject.por.fl_str_mv |
Alumínio AA6061 Deformação plástica severa criogênica Comportamento mecânico criogênico Extrusão em canal angular Precipitação |
topic |
Alumínio AA6061 Deformação plástica severa criogênica Comportamento mecânico criogênico Extrusão em canal angular Precipitação Aluminum AA6061 Cryogenic severe plastic deformation Cryogenic mechanical behavior Equal-channel angular pressing Aging ENGENHARIAS::ENGENHARIA DE MATERIAIS E METALURGICA |
dc.subject.eng.fl_str_mv |
Aluminum AA6061 Cryogenic severe plastic deformation Cryogenic mechanical behavior Equal-channel angular pressing Aging |
dc.subject.cnpq.fl_str_mv |
ENGENHARIAS::ENGENHARIA DE MATERIAIS E METALURGICA |
description |
The present work aimed two fronts: to characterize the mechanical behavior of the AA6061 alloy at cryogenic temperature, and to study the microstructural and properties evolution after cryogenic severe plastic deformation. Samples of AA6061 alloy were solution heat-treated and processed by conventional rolling, asymmetric rolling and equal-channel angular pressing (ECAP), both at room temperature and cryogenic temperature. After processing, such samples were treated for precipitation at 25 °C and at 100 °C, for different times. On the cryogenic mechanical behavior it was observed the suppression of the dynamic strain aging, which also allowed the ECAP processing without cracking. Uniform and total elongation and mechanical strength were always higher at -196 °C than at room temperature. The strain-rate sensitivity, despite having low values, becomes positive for cryogenic deformation, directly affecting the deformation capacity. Regardless of the processing route employed, a saturation of the hardness around 125 HV has been seen. The microstructures after cryogenic ECAP were very refined in relation to the starting material (average grain size up to 500 nm). In addition, it was observed a homogeneous strains distribution after cryogenic processing, with detection of several new fine grains from grain boundaries, which suggests recrystallization. The tensile tests results, after cryogenic processing in combination with artificial aging at 100 °C (48 hours), indicated an increase in uniform elongation. Regarding mechanical strength, the highest values were observed for extrusion at room temperature combined with artificial aging. In addition, there was to some static recovery during artificial aging, especially for cryogenic processing, which generates thermodynamically unstable microstructures. The density of dislocations, in fact, decreases with the prolongation of artificial aging time. Thus, the present study was based on a study of the cryogenic mechanical behavior of the AA6061 alloy, as well as the possibility of processing by cryogenic severe deformation. |
publishDate |
2017 |
dc.date.issued.fl_str_mv |
2017-08-08 |
dc.date.accessioned.fl_str_mv |
2018-02-20T12:12:38Z |
dc.date.available.fl_str_mv |
2018-02-20T12:12:38Z |
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info:eu-repo/semantics/publishedVersion |
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info:eu-repo/semantics/doctoralThesis |
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doctoralThesis |
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publishedVersion |
dc.identifier.citation.fl_str_mv |
MAGALHÃES, Danielle Cristina Camilo. Microestrutura e propriedades mecânicas da liga AA6061 processada por deformação plástica severa em temperatura criogênica. 2017. Tese (Doutorado em Ciência e Engenharia de Materiais) – Universidade Federal de São Carlos, São Carlos, 2017. Disponível em: https://repositorio.ufscar.br/handle/ufscar/9446. |
dc.identifier.uri.fl_str_mv |
https://repositorio.ufscar.br/handle/ufscar/9446 |
identifier_str_mv |
MAGALHÃES, Danielle Cristina Camilo. Microestrutura e propriedades mecânicas da liga AA6061 processada por deformação plástica severa em temperatura criogênica. 2017. Tese (Doutorado em Ciência e Engenharia de Materiais) – Universidade Federal de São Carlos, São Carlos, 2017. Disponível em: https://repositorio.ufscar.br/handle/ufscar/9446. |
url |
https://repositorio.ufscar.br/handle/ufscar/9446 |
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por |
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openAccess |
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Universidade Federal de São Carlos Câmpus São Carlos |
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Programa de Pós-Graduação em Ciência e Engenharia de Materiais - PPGCEM |
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UFSCar |
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Universidade Federal de São Carlos Câmpus São Carlos |
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