Influence of printed circuit board thickness in wave soldering

Abstract

This paper presents a thermal fluid–structure interaction (FSI) study of printed circuit boards (PCBs) during wave soldering. The influences of PCB thickness on displacement, stress and temperature distribution are the foci of the study. Five PCB thicknesses (i.e., 0.6, 1.0, 1.6, 2.4, and 3.1 mm) are considered. The paper focuses on a simple PCB with a single hole and constructed in a three-dimensional model. The thermal FSI of the PCB is solved by fluid (FLUENT) and structure (ABAQUS) solvers that are connected using the mesh-based parallel code coupling interface method. Molten solder advancement is tracked using volume-of-fluid technique in the thermal fluid analysis. ABAQUS solves PCB displacement, von Mises stress, and temperature distributions when high solder temperature is experienced during wave soldering. The correlations of PCB thickness to displacement, von Mises stress, temperature distribution, and molten solder filling time are studied. Results reveal that an increase in PCB thickness yields a linear correlation to solder filling time. Temperature distribution, von Mises stress, and displacement of PCB exhibit polynomial behavior to PCB thickness. A laboratory-scale two-way wave-soldering machine is also used to measure PCB temperature during wave soldering. The predicted temperature of PCB is substantiated by the experimental results.