Grain size effect on multiple-stage transformations of a cold-rolled and annealed equiatomic TiNi alloy

Ti50Ni50 shape memory alloy cold-rolled and annealed at specific conditions can exhibit a four-stage martensitic transformation. There are two small and two large peaks which are associated with the B2 → R → B19′ transformations of large grains in the specimen center and that of small grains near the rolling surface, respectively.