Effective transient process modelling of the reflow soldering of printed circuit assemblies

Process modelling of the reflow soldering of Printed Circuit Assemblies (PCAs) requires complex thermal models incorporating a number of modes of heat transfer, including radiation (infra red) and (forced/free) convection. This paper describes the development of representative process models of the reflow soldering of PCAs and outlines some of the more important parameters to consider for accurate simulation of the reflow process. Results are also presented illustrating the variation with temperature of critical properties for electronic materials, such as for FR-4 and epoxy based packaging materials.