A Thermal Fatigue Failure Mechanism of 58Bi-42Sn Solder Joints

Publisher Website
Google Scholar
Abstract
Surface mount components soldered with 58Bi–42Sn on printed circuit boards fell off after about 500 cycles of−45°C ↔ 100°C in a thermal chamber. Failure analysis revealed that the failure was caused by dissolving of Pb from either HAL (hot air leveled) board surfaces or component lead coatings into the Bi-Sn solder joints, forming 52Bi–32Pb–16Sn eutectic phase that melts at 95°C. The dissolving of Pb occurred primarily at reflow, when the Bi-Sn was molten. During the thermal cycling, the small amount (

This publication has 0 references indexed in Scilit: