ECAE Processed NiTi Shape Memory Alloy

Autor(es)

Carvalho Lucas, Fernanda Lidia ^[1] ; Guido, Vanessa ^[1] ; Kafer, Karine Andrea ^[2] ; Bernardi, Heide Heloise ^{[2, 3]} ; Otubo, Jorge ^[2]

Afiliação do(s) autor(es)

^[1] Univ Vale Paraiba UNIVAP, Sao Jose Dos Campos, SP - Brazil

^[2] ITA, Sao Jose Dos Campos, SP - Brazil

^[3] Fac Tecnol Sao Jose Dos Campos FATEC, Sao Jose Dos Campos, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: MATERIALS RESEARCH-IBERO-AMERICAN JOURNAL OF MATERIALS; v. 17, n. 1, p. 186-190, AUG 2014.
• Citações Web of Science: 2

Resumo

The current work evaluated the microstructures and martensitic transformation temperatures of NiTi shape memory alloy (SMA) deformed by equal channel angular extrusion (ECAE). The Ti-55.27wt.%Ni alloy was processed by 1 ECAE pass at 250 degrees C using a die with an intersection angle of 120. After processing, samples were annealed at 300 degrees C, 400 degrees C and 500 degrees C for 1h to evaluate the microstructural changes. Microstructural characterization was performed by scanning electron microscopy (SEM) equipped with an energy dispersive spectrometer (EDS) device, and Vickers hardness measurement. Martensitic transformations temperatures were analyzed by differential scanning calorimetry (DSC). Results show that the annealing treatments presented no significant change in the microstructure of the ECAE processed samples. Meanwhile, the DSC curves corresponding to the annealing treatments performed at 300 degrees C and 400 degrees C show two step martensitic transformation related to B2 -> R -> B19'. For the annealing at 500 degrees C, the martensitic transformation temperatures returned to the ST condition, indicating a reduction of the processing defects. (AU)

• Processo FAPESP: 07/08265-2 - Caracterização de superfícies tratadas com laser por difração de raios-X
• Beneficiário: Milton Sergio Fernandes de Lima
• Linha de fomento: Auxílio à Pesquisa - Regular
• Processo FAPESP: 00/09730-1 - Desenvolvimento de ligas de NiTi com efeito de memória de forma
• Beneficiário: Jorge Otubo
• Linha de fomento: Auxílio à Pesquisa - Apoio a Jovens Pesquisadores
• Processo FAPESP: 10/20565-4 - Influência da deformação plástica severa e de precipitados intermetálicos em ligas inoxidáveis Fe-Mn-Si-Cr-Ni-Co-(Ti) com EMF
• Beneficiário: Karine Andrea Kafer
• Linha de fomento: Bolsas no Brasil - Doutorado