Modeling of Combined Temperature Cycling and Vibration Loading on PBGA Solder Joints Using an Incremental Damage Superposition Approach

Concurrent vibration and temperature cycle environments are commonly encountered in the service life of many electronic products, particularly those used in automotive, avionic, and military applications. However, the ability to predict life expectancy under these types of environments remains a technical challenge. In this paper, a traditional linear damage superposition modeling approach and a damage superposition approach that considers the temperature imposed load state on vibration damage are compared with experimental test results for plastic ball grid array (PBGA) assemblies subjected to temperature cycling, vibration loading, and combined temperature cycling and vibration loading conditions. The results showed much earlier PBGA solder-joint failure under combined loading than with either separate temperature cycling or room temperature vibration loading. Traditional linear superposition was found to over-predict the solder-joint fatigue life, since it neglects the interaction effects of two different loadings. The damage superposition approach that considers the temperature imposed load state on vibration damage is found to be more representative of test data.