Effect of Cold Rolled on Microstructure and Mechanical Properties of TiNi Shape Memory Alloy

Abstract

The effect of cold rolled reductions on microstructure and mechanical properties of TiNi alloys was investigated by means of tension test and TEM. From the results it can be determined that when the annealing temperature reached 550℃, the recrystallization and grain growth began to occur after the cold deformation, and the tensile strength of the alloy decreased greatly and the elongation was more than 50%. The stress platform of stress-strain curves was decided by cold deformation and annealing temperature, which meets the Clasusius-Clapeyron equation. When the alloy rolled above 37%, large deformation energy storage is conducive to the occurrence of recrystallization. The microstructure evolves form recovery to nucleation of amorphous structures, recrystallization and grain growth as the rising of annealing temperature.