Temperature- and rate-dependent deformation behaviors of SAC305 solder using crystal plasticity model

To describe the mechanical properties of Sn-3.0Ag-0.5Cu (SAC305) solder under loading, uniaxial tensile experiments were conducted at different temperatures and strain rates. A crystal plasticity finite-element model was used to investigate the influence of both temperature and strain rate on the deformation behavior of beta-Sn in SAC305 solder via the representative volume element. A systematic analysis of the influence of grain numbers and orientations showed that random grain orientation is important in determining the dispersion of the poly-crystalline macroscopic stress-strain curves. Furthermore, by adjusting the temperature-dependent parameters based on the slip mechanism, the model was successfully applied to describe the temperature-dependent characteristic of the SAC305 solder. With increasing temperature, the difference in stress-strain response between different strain rates of the SAC305 solder was narrowed by a phenomenon in which the rate-dependent effects were weakened. This phenomenon was also simulated by the model with a modification of the rate-dependent parameter.

Automated summary

In this study, the mechanical properties of SAC305 solder were investigated under different temperatures and strain rates using experimental and modeling approaches. The results showed that grain orientation played a crucial role in determining the dispersion of poly-crystalline macroscopic stress-strain curves, and adjustments of parameters could successfully describe the temperature-dependent behavior of the solder. Moreover, the rate-dependent effects on the stress-strain response of SAC305 solder were weakened with increasing temperature, which was simulated by modifying the rate-dependent parameter in the model.