一级固态相变中的耗散函数Ⅱ。VO_2中的变温结构转变

The Dissipation Function of the First-order Phase Transformation Ⅱ.Structural Phase Transformaion in VO_2

测量了多晶VO_2在结构相变过程中的低频内耗和模量随温度、变温速率以及测量频率的变化,观测到相变内耗峰和明显的模量极小值。利用内耗和模量随升温速率及测量频率变化的数据,计算出了VO_2陶瓷在升温相变过程中的耗散函数⊿G_R(T)。它表征了相变过程中的能量耗散率和相界面的动性。

The dependence of internal friction and modulus on temperature,temperature varying rate and frequency are experimentally investigated for VO_2 ceramics in the process of structural phase transformation(PT).An internal friction peak and a minimun of modulus are observed during the PT process.The dissipation funct on of VO_2 ceramics is obtained by using the experimental data,and the dissipation function is shown to characterize the energy dissipation rate of the structural PT and the mobility of the phase interface.