Thermal cycling behavior of an aged FeNiCoAlTa single-crystal shape memory alloy

In this study the thermal cycling behavior of differently aged [1 0 0]-oriented Fe–28Ni–17Co–11.5Al–2.5Ta (at.%) shape memory single crystals was investigated. The strain–temperature response determined from thermal cycling experiments revealed a strong dependency on the precipitate morphology, which was adjusted by aging heat treatments. Specifically, a high precipitate density in the microstructure leads to small phase transformation-induced strains and low stresses necessary for activation of the martensitic phase transformation.