第一性原理计算Fcc-Cr_(1-x)Si_xN的调幅分解

First Principles on Spinodal Decomposition of Fcc-Cr_(1-x)Si_xN

基于通过第一性原理计算方法,计算了三元固溶体Fcc-Cr1-xSixN总能,在此基础上计算了其分离能和调幅分解线.结果说明,Fcc-Cr1-xSixN是亚稳相,能够经调幅分解机制分解为Fcc-CrN和Fcc-Si N.组元相形成的应变能小于分离能,不会抑制Fcc-Cr1-xSixN的调幅分解.Fcc-Cr1-xSixN的Si含量为渗透阈值时,不会发生调幅分解.Fcc-Cr1-xSixN可能经调幅分解生成Fcc-Si N.

Total energies of ternary solution Fcc-Cr1-xSixN phase were calculated by first principle method,and de-mixing energy and spinodal curve of Fcc-Cr1-xSixN phase were calculated.The results showed that Fcc-Cr1-xSixN is metastable and apt to decompose to Fcc-CrN and Fcc-SiN via spinodal decomposition.The strain energy between the constituent phases was smaller than the de-mixing energy,which couldn＇t hinder the spinodal decomposition.Spinodal decomposition could not proceed for Si composition of Fcc-Cr1-xSixN identical to the percolation threshold.Fcc-Cr1-xSixN and decompose to Fcc-SiN via the coherent spinodal decomposition.