热弹性马氏体相变中的高温内耗峰

High-Temperature Internal Friction Peak in Thermoelastic Martensitic Transformation

采用不完全相变内耗(IF)测量法,在Cu-Al-Ni-Mn-Ti合金马氏体相变中获得双内耗峰,即低温内耗峰和高温内耗峰。高温内耗峰主要出现在频率小于0.050 Hz的范围,其位置对应于相对动力学模量的拐点位置;高温内耗峰峰值在测量频率范围内与振动频率成反比关系,满足经典的Belko和Delorme模型;高温内耗峰具有明显的反常应变振幅效应,其峰值随变温速率的增大而增大,这些都说明高温内耗峰的形成与相转变量有关。

Two internal friction （IF） peaks, the lowtemperature IF peak and the high-temperature IF peak, were obtained in martensitic transformation of Cu-Al-Ni-Mn-Ti alloy through partial phase transition method. The high-temperature IF peak primarily appeared where the frequency was less than 0. 050 Hz and it corresponded to the inflexion point of relative dynamic modulus. The maximum of the high-temperature IF peak was inversely proportional to the frequency within the measuring frequencies, which was in accordance with the classical models of Belko and Delorme. The high temperature peak had a clear abnormal effect on strain amplitude, and its maximum increased with the increase of heating rate, which all suggested that it corresponded to the value of phase transformation.