IN-PROCESS BOARD WARPAGE MEASUREMENT IN A LAB SCALE WAVE SOLDERING OVEN

An automated on-line warpage measurement system for printed wiring boa rds (PWB's) and printed wiring board assemblies (PWBA's) has been deve loped. The system is capable of simulating a variety of soldering proc esses, including the wave soldering process, and performing real-time PWB/PWBA warpage measurements using the shadow moire technique. The sy stem can be used to characterize the warpage behavior of virtually any PWB/PWBA during the soldering process. Using this system, warpage of PWB test vehicles was measured during simulated wave soldering. The me asured warpage varied significantly during wave soldering from that ob served both before and after wave soldering. These results help us to understand how the board deforms at every stage of the soldering proce ss.