Autor: |
Gama, J. L. L., Dantas, C. C., Quadros, N. F., Ferreira, R. A. S., Yadava, Y. P. |
Předmět: |
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Zdroj: |
Metallurgical & Materials Transactions. Part A; Jan2006, Vol. 37 Issue 1, p77-87, 11p, 1 Diagram, 5 Charts, 6 Graphs |
Abstrakt: |
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 γ2 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 γ2 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 properly. [ABSTRACT FROM AUTHOR] |
Databáze: |
Complementary Index |
Externí odkaz: |
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