Property of TiNi Shape Memory Foils Produced by Ultrafine Laminates Method

摘要

Using the ultrafine laminate method, thin foils (50 μm) of Ni-rich TiNi shape memory alloys were produced. Overall composition of the Ti/Ni laminate is Ti-50.7%Ni. TiNi (B2) phase was obtained after different diffusion treatments at 1073 K for 36 ks. Aging treatment at 773 K for 3.6,18, 36, 72 and 144 ks were also performed. Phase transformation behavior of aged foils changed from two-step, to three-step and then to two-step transformation, which is similar to the case of bulk TiNi alloys. Uniform distribution of Ti_3Ni_4 phase was observed for aged samples by transmission electron microscopy. Two-way shape memory effect of the aged TiNi foil was also demonstrated.