STUDY OF THERMO-MECHANICAL TREATMENT AND MN, TI ADDITIONS OF CU-AL-NI SHAPE MEMORY ALLOYS

Abstract

There is no comprehensive study on the combined effect of both thermomechanical treatment and modification with alloying elements on the shape memory properties of Cu-Al-Ni shape memory alloy (SMAs). Therefore, this work aimed at studying the effect of 85% thickness reduction through hot deformation as well as heat treatment on the martensitic transformation of Cu-Al-Ni-Ti-Mn SMAs. The samples were divided into two groups: the first group was solution treated at 900°C for 30 min. (S.T), and the other group was hot-rolled at 900°C followed by solution treatment at 900°C for 30 min. (H.R.S.T). The results showed that the hardness of the samples decreased with increasing the percent of Ni. The DSC investigations revealed that the martensite start temperature (Ms) decreased due to the addition of both Ti and Mn compared to the predicted Ms reported in the literature.