REMAP Materials Project M2: High Temperature High Humidity Corrosion and Tin Whisker Evaluation of Bi Containing Lead-Free Alloys
Authors: Polina Snugovsky, Stephan Meschter, Jeff Kennedy, and Zohreh Bagheri Company: Celestica Inc. and BAE Systems Date Published: 5/9/2016
ICSR (Soldering and Reliability)
Abstract: The introduction of environmental legislation such as the European Union's Restriction of Hazardous Substances (RoHS) directive has led to the use of new tin-based solder alloys in electronics manufacturing. These alloys have shown a susceptibility to the spontaneous growth of filaments known as tin whiskers. Over time, this can cause field failures in high-reliability applications such as aerospace, medical and automotive electronics. This project will focus on the greening of aerospace electronics materials to reduce the risk of tin whiskers and increase electronics reliability for applications that are exposed extreme conditions. The whisker growth and corrosion of assemblies soldered with Bi additions to Sn-Ag-Cu and Sn-Cu alloys were evaluated in high temperature/high humidity 85C and 85 percent relative humidity environments using boards with ENIG and immersion Sn board finishes.