Cu-Al-Ni-Mn-Ti合金在不完全相变过程中的内耗行为研究

文章采用不完全相变内耗(IF)测量法研究了Cu-Al-Ni-Mn-Ti多晶形状记忆合金在热弹性马氏体相变时内耗峰与外界变量(频率、升温速率及不完全相变开始测量温度Ts)的依赖关系。实验结果表明,测量频率小于0.045Hz时,内耗峰分解成双峰(低温PL峰和高温PH峰),随Ts的降低,双峰逐渐合并;PL峰值与频率对数呈现峰形函数关系,随升温速率的增加,PL峰向高频方向移动,相变弛豫时间减小;PH峰值与频率倒数成线性关系,随升温速率的增加,线性斜率变大。

Behavior of internal friction of Cu-Al-Ni-Mn-Ti alloy in the process of incomplete phase transition

An incomplete phase transition method was used in internal friction(IF) measurement to study the relation of the IF peak with external variables(frequency,heating rate and incomplete transition temperature Ts) in thermoelastic martensitic transformation of Cu-Al-Ni-Mn-Ti polycrystalline shape memory alloy.The experimental results show that one single IF peak is actually made up of two different peaks(PL peak at low temperature and PH peak at high temperature) when the measurement frequency is less than 0.045 Hz.The double peaks are gradually combined as the incomplete transition temperature Ts falls.The maxima of PL peaks plot a symmetrical peak-like curve at the logarithmic frequency spectrum and the PL peaks in the frequency spectrum shift toward high frequencies with the increase of heating rate,indicating that the phase transition relaxation time decreases.The maxima of PH peaks exhibit a linear relation to the reciprocal frequency,and as the heating rate increases,its slope rises.