High Strain-Rate Properties for SAC305 at Cold Operating Temperatures down to -65°C

Abstract

In the industries like aerospace applications, medical applications and in oil/gas exploration, the electronic components can be exposed to very cold temperatures. In addition, these electronic packages and assemblies may be subjected to vibrations, shocks and impacts. In such harsh surrounding, electronic components may face strain rates of 1 to 100 per seconds and low surrounding temperature up to - 65°C. The records are not available for lead-free solder alloys tested at cold operating temperature and at high strain rates. Earlier published results for SAC305 lead-free solder alloys is restricted to low strain rates and high operating temperatures. For the material SAC305, records are not available for low operating temperatures. In this paper, lead-free solder alloy SAC305 has been tested and studied at several lower surrounding temperature starting from -65°C up to 0°C, with high strain rates. The prepared SAC305 lead-free alloy specimen after reflowing, have been tested at strain rates of 10, 35, 50, and 75 per sec at multiple operating temperatures ranging from -65°C to 0°C. Stress-strain curves are plotted for various low operating temperatures and for the range of strain rates. The calculated experimental data has been fit to the Anand Viscoplasticity model for SAC305 and the Anand constants are established by forecasting the measured stress- strain behavior for the various lower temperatures and high strain rates.