表面组装焊点内部应力—应变场的数值模拟(Ⅰ)——应力—应变场分布特征及其动态特性

Finite element analysis of stress strain distribution characteristics in SMT solder joints (Ⅰ) ——Dynamic feature of stress strain field distribution

针对表面组装焊点的实际服役条件 ,对温度循环载荷下其内部应力—应变场的分布特征进行了有限元数值模拟。结果表明 ,温度循环在焊点内部导致应力循环 ,应力循环导致热棘轮效应 ,即非弹性应变累积 ;在温度历史过程中 ,应力—应变场等值分布图呈现动态特性 ,且与温度历史相关。

Based on the real service conditions of surface mount solder joints, the finite element numerical simulation was made in order to get the feature of stress strain distribution in the solder joints under temperature cycling. Analysis results show that temperature cycling leads to stress cycling and the later leads to thermal ratchetting effect and the accumulation of inelastic strain. Furthermore, stress strain distribution in the solder joints has dynamic feature during temperature cycling and is related to temperature history. [