Study on shear strength and fracture path of laser ball planting solder joint

In order to improve the reliability of laser ball solder joint, the influence of different process parameters on the shear strength of laser ball planting solder joint and the fracture path of solder joint under different shear conditions were analyzed. Sac solder ball with a diameter of 500 μm is used in the experiment and Au-Ni/P-Cu is used as substrate. The solder joints are prepared by laser ball planting machine. Through the orthogonal test, range and variance analysis, it is found that the laser power has the greatest influence on the shear strength of the solder joint, and the optimal combination of process parameters is inferred. Through the change of shear parameters, the fracture surface of the solder joint is observed by electron microscope (SEM) and its fracture path is analyzed. It is found that the fracture path of the solder joint is changed by reducing the shear height and accelerating the shear speed and the solder joint will change from complete ductile fracture to brittle fracture. It provides a certain reference significance for improving the strength of the solder joint in the process of laser ball planting, and the use of devices under different external conditions,