封装器件多应力叠加失效仿真分析与验证

针对某双列直插式(DIP)封装器件在整机温循试验中出现的失效现象,分析在器件与电路板焊接环节、电路板与整机装配环节和整机温循试验环节3个工况下可能的失效原因,对原因分别进行单工况和多工况的失效仿真分析。针对不同仿真模型在不同工况下的叠加仿真难题,提出基于ANSYS Workbench有限元软件的多应力叠加仿真方法,对比单一工况和多种工况下的仿真结果。结果表明,DIP封装器件失效是器件在焊接尺寸不匹配、过定位装配和温循试验三种工况下,机械应力和热应力的叠加使玻璃绝缘子产生裂纹导致的,有限元仿真结果与实验结果基本吻合,为DIP封装器件在多工况下应力叠加失效的故障机理研究提供一种可参考的仿真方法。

Failure Simulation Analysis and Verification of the Package Device Under Multiple Stress Superposition Situation

Based on the failure of a DIP package device occurred in the machine temperature cycle test,failure simulation analysis with possible failure reasons under single and multiple working conditions are respectively performed through three periods including welding between the module and PCB,assembly between the machine and PCB and the machine temperature cycle test.Because of the superposition simulation problem for different simulation models under different working conditions,a stress superposition simulation method based on the finite element software ANSYS Workbench is proposed.The conclusion is made from simulation results comparison between single and multiple working conditions:the failure of DIP package device is caused by the glass insulator crack under combined action of mechanical stress and thermal stress under three working conditions including welding size mismatch,over-positioning assembly and temperature cycle test.The finite element simulation results are basically consistent with the test results.A simulation method is provided with the stress superposition for the failure analysis of DIP package devices under multiple working conditions.