Method of predicting thermal fatigue life of lead-free solder joints

摘要

An acceleration formula of a temperature cycle test was developed by using a specimen consisting of a paper-phenolic printed-circuit board and a connector made from nylon 66, joined to each other with lead-free solder. This setup enabled the prediction of the Sn-Ag-Cu lead-free solder joints' life in actual operating conditions by using temperature cycling tests. In deriving the acceleration formula, an unknown number n and activation energy were quantified based on the experimental equation by Conffin-Manson.