【摘要】 采用非线性有限元方法,讨论了片式元件与基板的间隙对Sn-2.5Ag-0.7Cu无铅钎料焊点的应力分布和热疲劳寿命的影响。结果表明,当间隙高度为0.1~0.2mm时,焊点薄弱处——元件底部拐角处、焊根的顶部和底部以及焊趾顶部具有较低的应力,此时预测得到焊点的热疲劳寿命也最长。这一结果对于焊点几何形态的设计及优化具有指导意义。更多还原

【Abstract】 The effects of stand-off height between chip component and substrate on the stress-strain distribution situation and thermal fatigue life of Sn-2.5Ag-0.7Cu lead-free solder joint were investigated by nonlinear finite element method.The results show that when stand-off height between 0.1~0.2 mm,the equivalent stress is lower at the bottom corner of the component,the top and bottom of root of weld and the top of toe of weld.At the same time,the thermal fatigue life of solder joint is also the longest.The results are of importance to design and optimize of geometry shape of the solder joint.更多还原