[摘要]：The Ti-Ni-W two-phase shape memory alloy (SMA) thin film system is presented as a prototype for new SMAs with tailorable thermal transformation hysteresis (Delta T). The concept is to combine the SMA TiNi with almost insoluble W to create the two-phase system (TiNi)-(beta-W). This system behaves like a pseudobinary TiNi system. Phase transformation behavior for compositions above the solubility limit of W in TiNi exhibit a B2-R phase transformation with characteristically small Delta T. Moreover, Delta T is dependent on the amount of W and it can be tailored to zero and even negative. This phenomenon is rationalized as being due to the mechanical interaction between the phases B2-TiNi and beta-W. The presented results are very promising for the development of high-speed Ti-Ni-based SMA actuators.
