The superelastic anisotropy in a NiTi shape memory alloy thin sheet

Two approaches were taken to determine the most favorable martensite variants and the corresponding theoretical transformation strains. One is based on the resulted transformation strain according to austenite-martensite lattice correspondence, and the other is based on the Schmid factor. Interestingly, both methods have led to the same sets of martensite variant hence the same values of theoretical transformation strain. This is discussed based on recent observations of the stress-induced martensite in NiTi.