Determination of Smarter Reflow Profile to Achieve a Uniform Temperature Throughout a Board
Yangyang Lai, Ke Pan, Jiefeng Xu, Junbo Yang, Seungbae Park
Abstract
Uneven temperature distribution poses a big challenge on reflow soldering of surface mount components. Particularly, when components with different thermal mass are mounted on a large size of PCB, temperature gradient across the board can cause various assembly defects. Formation of a robust solder joint is closely associated with solder temperature profile which is hard to be measured experimentally. numerical simulation is an effective method to predict the solder joint temperatures which can be used as a reference to optimize the reflow profile.In this study, CFD modeling was developed to simulate solder joint temperature profile in reflow process. The profile is not a single line, but a band or process window. to achieve a good soldering quality, the non-uniformity of the solder temperatures should be within the recommended temperature profile band. The optimized thermal profiles and corresponding temperature setting of reflow oven can contribute to actual experiment and production.