(中国科学院 上海冶金研究所， 上海 200050)
摘 要: 对电子封装IGBT功率模块进行热循环实验，考察了92.5Pb5Sn2.5Ag钎料焊层的热循环失效和裂纹扩展。应用超声波显微镜对裂纹扩展过程进行检测，得到了热循环失效的裂纹扩展数据。采用统一型粘塑性Anand方程描述了92.5Pb5Sn2.5Ag的力学本构，模拟了功率模块钎料焊层裂纹体在热循环条件下的应力应变。基于对ΔJ积分的求解，描述了PbSnAg焊层热循环裂纹扩展速率。
关键字: 92.5Pb5Sn2.5Ag钎料； 热循环；裂纹扩展； 粘塑性；ΔJ积分
（Shanghai Institute of Metallurgy， The Chinese Academy of Science，
Abstract:By applying thermal cycling tests to the IGBT power modules， the thermal fatigue and crack propagation of 92.5Pb5Sn2.5Agsolder layer were investigated. The crack propagation process in solder layer was inspected with Cmode scanning acoustic microscope (CSAM) and the crack propagation data were also measured. By employing the unified viscoplastic Anand constitutive equation to represents the deformation behavior of 92.5Pb5Sn2.5Ag solder，the stress/strain responses of the power modules with crack in PbSnAg solder layer under thermal cycling were simulated with finite element method. Moreover，the crack propagation rate of PbSnAg solder layer under thermal cycling was described based on the calculationof mechanical parameter ΔJ integral.
Key words: 92.5Pb5Sn2.5Ag solder; thermal cycling; crack propagation; viscoplastic; ΔJ integral
