Two internal-friction peaks related to thermoelastic martensitic transformations in CuAlNiMnTi shape-memory alloy

摘要

A partial phase transition method was used in internal friction measurements to study the motion of phase interface in martensitic transition of CuAlNiMnTi polycrystalline shape memory alloy. It is found that the IF peak arisen from the reversible martensitic transition is in fact composed of two independent IF peaks that relate to different motion modes of the interface. The low-temperature peak corresponds to the minimum of relative dynamic modulus and is attributed to an elastic modulus softening effect caused by the viscous motion of the phase interface. The high-temperature peak corresponds to the inflection point of the relative dynamic modulus and the volume change produced by the normal motion of the phase interface is responsible for the peak.