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Eric Marchezini Mazzerhttp://lattes.cnpq.br/7273276940567054Pedro Henrique Rodrigues PereiraWitor WolfErnane Rodrigues da Silvahttp://lattes.cnpq.br/6195935306390779Herbert Eustáquio da Silva Junior2022-11-21T16:54:50Z2022-11-21T16:54:50Z2020-03-20http://hdl.handle.net/1843/47352As transformações martensíticas (MT) existentes nas ligas com memória de forma (SMA) são do tipo termoelástica e são as responsáveis por conferir a essa classe de materiais características únicas de memória de forma e pseudoelasticidade, que as tornam interessantes para aplicações em atuadores de movimento, sensores, amortecedores de impacto, absorção/liberação de energia, materiais elastocalóricos, entre outros. Dentre as principais ligas com memória de forma encontram-se as do sistema Ni-Ti. Em altas temperaturas, as ligas a base de Cu são uma alternativa de baixo custo para a substituição dessas, com desempenho satisfatório das propriedades funcionais. Entretanto, as ligas de Cu são susceptíveis à fratura intergranular frágil, devido à sua alta anisotropia elástica. Neste contexto, com o objetivo de modificar a microestrutura da liga e contornar as dificuldades supracitadas, a liga deste trabalho, do sistema Cu-Al-Ni, foi conformada por Spray e submetida a um processo de deformação plástica severa (Severe Plastic Deformation - SPD), denominado torção sob elevada torção (High-Pressure Torsion - HPT), com 0, 1/16 e 1/2 volta. Para a identificação das fases foi utilizada a Difração de raio-X (XRD). O comportamento mecânico foi avaliado pelos testes de Microdureza Vickers. A medição dos tamanhos de grãos gerados foi realizada com o auxílio da Microscopia Óptica (OM), enquanto as morfologias formadas foram analisadas pelo Microscópio Eletrônico de Transmissão (TEM). Para o entendimento da variação da propriedade funcional de memória de forma foram utilizadas as análises de Calorimetria Diferencial de Varredura (DSC), Microscopia de Força Atômica (AFM) e Microscopia Eletrônica de Varredura (MEV). Os resultados comprovaram a efetividade do processamento por HPT, com o aumento da dureza da amostra e redução do tamanho de grão. A predominância da fase martensita β’ e a formação de ripas martensíticas auto-acomodadas sugeriram a manutenção da propriedade funcional de memória de forma, que, mais tarde, foi comprovada pela verificação da recuperação da forma em todas as rotas de processamento deste trabalho.The martensitic transformations (MT) existing in shape memory alloys (SMA) are thermoelastics and are responsible for providing unique features for this class of materials, such as shape memory and pseudoelasticity, which make them interesting for applications in motion actuators, sensors, damping devices, energy absorption/release, and elastocaloric materials. The Ni-Ti system is one of the most important SMA. At high temperatures, Cu-based alloys are a low-cost alternative to replace them, with satisfactory performance of functional properties. However, they are susceptible to fragile intergranular fracture, due to their high elastic anisotropy. In this context, an alloy from the Cu-Al-Ni system was formed by Spray and exposed to a severe plastic deformation process (SPD), called High Pressure Torsion (HPT), with 0, 1/16 and 1/2 turns, in order to modify the microstructure of the alloy overcoming the difficulties previously exhibited. X-ray diffraction (XRD) was used to identify the phases formation. The mechanical behavior was evaluated by Vickers Microhardness tests. The measurement of the produced grain sizes was performed by Optical Microscopy (OM), while the morphologies were analyzed using a Transmission Electron Microscope (TEM). Aiming at understanding the variation of functional memory shape, it was carried out Differential Scanning Calorimetry (DSC), Atomic Force Microscopy (AFM), and Scanning Electron Microscopy (SEM). The results proved the effectiveness of the HPT processing, due to the increase of the hardness and reduction of the grain size. The predominance of the β’ martensite phase and the formation of self-accommodating martensitic fine plates suggested the maintenance of the shape memory functional property, which was further corroborated by the shape recovery in all processing routes used in this work.porUniversidade Federal de Minas GeraisPrograma de Pós-Graduação em Engenharia Metalúrgica, Materiais e de MinasUFMGBrasilENG - DEPARTAMENTO DE ENGENHARIA METALÚRGICAEngenharia metalúrgicaMetalurgia físicaLigas (Metalurgia)Propriedades mecânicasLigas com memória de formaCu-Al-NiSprayHPTPropriedades mecânicas e funcionalCaracterização mecânica e funcional de uma liga com memória de forma do sistema Cu-Al-Ni-Mn conformada por spray e deformada por HPTinfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/masterThesisinfo:eu-repo/semantics/openAccessreponame:Repositório Institucional da UFMGinstname:Universidade Federal de Minas Gerais (UFMG)instacron:UFMGORIGINALCARACTERIZAÇÃO MECÂNICA E FUNCIONAL DE UMA LIGA COM MEMÓRIA DE FORMA DO SISTEMA Cu-Al-Ni-Mn CONFORMADA POR SPRAY E DEFORMADA POR HPT.pdfCARACTERIZAÇÃO MECÂNICA E FUNCIONAL DE UMA LIGA COM MEMÓRIA DE FORMA DO SISTEMA Cu-Al-Ni-Mn CONFORMADA POR SPRAY E DEFORMADA POR HPT.pdfapplication/pdf11557493https://repositorio.ufmg.br/bitstream/1843/47352/1/CARACTERIZA%c3%87%c3%83O%20MEC%c3%82NICA%20E%20FUNCIONAL%20DE%20UMA%20LIGA%20COM%20MEM%c3%93RIA%20DE%20FORMA%20DO%20SISTEMA%20Cu-Al-Ni-Mn%20CONFORMADA%20POR%20SPRAY%20E%20DEFORMADA%20POR%20HPT.pdf9aa7aa0efe9e92ba9ef80844ba6909e0MD51LICENSElicense.txtlicense.txttext/plain; charset=utf-82118https://repositorio.ufmg.br/bitstream/1843/47352/2/license.txtcda590c95a0b51b4d15f60c9642ca272MD521843/473522022-11-21 13:54:50.889oai:repositorio.ufmg.br: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ório InstitucionalPUBhttps://repositorio.ufmg.br/oaiopendoar:2022-11-21T16:54:50Repositório Institucional da UFMG - Universidade Federal de Minas Gerais (UFMG)false
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