Microstructure-mechanical property relationship to copper alloys with shape memory during thermomechanical treatments

• Published in: Metallurgical and materials transactions. A, Physical metallurgy and materials science Physical metallurgy and materials science, 2006, Vol.37 (1), p.77-87
• Main Authors: GAMA, J. L. L, DANTAS, C. C, QUADROS, N. F, FERREIRA, R. A. S, YADAVA, Y. P
• Format: Article
• Language: English
• Subjects: Alloys; Applied sciences; Deformation; Exact sciences and technology; Grain growth; Mechanical properties; Mechanical properties and methods of testing. Rheology. Fracture mechanics. Tribology; Metals. Metallurgy; Microstructure; Recrystallization
• ISSN: 1073-5623; 1543-1940
• DOI: 10.1007/s11661-006-0154-3

The phase transformations during fabrication and aging after cold deformation in three polychrystalline copper alloys of the Cu-Al-Ni system with shape memory effect (SME) were characterized. Some phase transformations were identified with clear repercussion in their mechanical properties during thermomechanical treatments. Around 430 °C, mutual effects of β-phase recrystallization and precipitation of γ^sub 2^ and NiAl phases were observed. Close to 600 °C the dissolution of phase α was observed, beginning transformation into β phase process. Brittle phases such as γ^sub 2^ and NiAl began to precipitate during a short exposure time at 380 °C, 585 °C, 600 °C, and 700 °C temperatures. The phase transformations were intensified due to the plastic deformation that acted as a driving force for the diffusion processes. The introduction of chemical elements inhibited the grain growth and increased the structural disorder generating an elevation in the hardness property. [PUBLICATION ABSTRACT]