Influence of Laser Soldering Temperatures on Through-Hole Component

The conventional method of selective soldering has been practiced using wave soldering, convection reflow, and hand soldering. However, due to industry automation and high demand for quality, repeatability and flexibility, laser soldering process has been developed to meet these demands. This article investigates the effect of different temperature of laser soldering process on lead-free solder (SAC305) by means of numerical method that is validated by experiment. Finite volume method (FVM) was used for the three-dimensional simulation to simulate the filling flow of the lead-free solder. Experiments were carried out to complement simulation validity and the results of both methods show good agreement. The findings show that a better result can be achieved when the angle of component lead (θ_le) approaches 90 deg. Using optimized lead angle, five different temperature simulations were set in the range of 550 K < T < 700 K. The finding shows that 600 K has the best velocity and pressure distributions with average values of 63.3 mm/s and 101.13 kPa, respectively. The high-pressure regions are concentrated at the top and bottom surface of solder pad. High difference in pressure and velocity spots somehow lead to issue associated with possibility of incomplete filling or void formation. 650 K model shows less void formation since it produces high pressure filling flow within the solder region.