Original paper(Vol.46 No.8 pp.900)

Analysis of uniaxial behavior of an Fe based shape memory alloy under cyclic thermomechanical loading

Nishimura Fumihito; Watanabe Noriko; Tanaka Kikuaki

Abstract:The thermomechanical hysteretic behavior of an Fe based shape memory alloy is phenomenologically analyzed under cyclic uniaxial tensile and compressive loading. The shift of the stress strain temperature hysteresis loop, expressed by means of the evolution of the residual strain, is well explained by the theory with some internal variables. The accumulated perfect dislocations formed as a result of the interaction of martensite plates is one of the internal variables introduced here. The back stress is also employed as an internal variable to be the driving force for the shape recovery for the martensite plates. The simulations describe well the hysteretic behavior under the strain and stress controlled cyclic thermomechanical loading; the shift of a loop, evolution of the residual strain and the change in transformation stress.

Key Words:Fe-based shape memory alloy, cyclic loading, tension and compression, hysteretic behavior