A Study on the Shape Memory Characteristic Behaviors of Ti-42.5at%Ni-10at.% Cu Alloys

Ti-42.5at.%Ni-10at.%Cu합금의 형상기억특성에 관한 연구

  • Published : 2009.02.28

Abstract

Shape memory recoverable stress and strain of Ti-42.5at%Ni-10at%Cu alloys were measured by means of constant temperature tensile tests. The alloys' transformation behavior is B2 - B19 by DSC result. The strain by tensile stress were perfectly recovered by heating at any testing conditions but shape memory recoverable stress increased to 66MPa and then slightly decreased. Transformation temperatures from thermal cycling under constant uniaxial applied tensile loads linearly increased by increasing tensile load and their thermal hysteresis are about 110K and their maximum recoverable strain is 6.5% at 100MPa condition.

Keywords

shape memory;solutionized alloy;differential scanning calorimeter(DSC);transformation temperature;austenite;martensite;recoveralbe stress;recoverable strain

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