关键词: 关键词:TEC, 焊点, 热疲劳寿命, 有限元分析方法

Abstract: In order to study the problem of solder joint cracking in TEC during high and low temperature power on/off experiments, finite element analysis method was used to analyze the thermal stress of TEC solder joints during power on/off. The stress analysis results showed that power on/off would cause the upper solder joint to undergo more high and low temperature cycles, and temperature cycles would produce alternating thermal stress on the solder joint. Moreover, the thermal stress change of the upper solder joint was greater than that of the lower solder joint, resulting in the upper solder joint being more prone to fatigue cracking. By equating one power on/off cycle at high and low temperatures to one high and low temperature cycle, the creep strain energy density of the upper solder joint in each cycle was calculated. Based on the creep strain energy density, the life of the upper solder joint under TEC power on/off conditions was predicted. The predicted number of power on/off cycles has reference significance for evaluating the service life of TEC.

Key words: TEC, solder jiont, thermal fatigue life, finite element analysis