Modeling stress strain curves for lead-free 95.5Sn-3.8Ag-0.7Cu solder

Mechanics of materials characterization of lead-free solder mechanical properties and stress strain curve properties are needed for applications in finite element analysis. In this study, tensile properties for lead-free 95.5Sn-3.8Ag-0.7Cu solder alloy were obtained from bulk tensile specimen tests. A modified Ramberg-Osgood model was developed to describe the temperature and strain rate dependent stress-strain curves for the solder alloys. The modified Ramberg-Osgood model is able to predict the temperature and strain rate effects on the stress-strain properties for lead free 95.5Sn-3.8Ag-0.7Cu solder alloy. Comparison between the proposed modified Ramberg-Osgood model and the Anand viscoplastic model is made in predicting the stress-strain data obtained from the constant strain rate tensile tests.