用云纹干涉法研究金属焊点的热变形问题

Experimental Study on Thermal Strains in Bimetal Joint by Moire Interferometry

本文采用现代光测力学的云纹干涉法，对铜－可伐焊接件热应变问题进行了实验研究，确定了焊层的热应变特征，结果表明：由于热膨胀系数不匹配、焊层存在复杂的应力状态，它不仅受到焊板材料对它的剪切作用，而且受到纵向拉伸、挤压作用。

The thermal strain of bimetal soldering joint (Cu and Kovar) is analysed with moire interferometry method. The thermal strain distribution along the soft solder (62Sn 36Pb 2Ag) is determined. It is shown from the results that there exists in the solder layer a complicated state of thermal strain. This is important for understanding the thermal fatigue failure mechanism in electronic package.