Effect of thermal cycling on tensile behaviour of SAC305 solder

Thermal cycling is typical working environment of electronic chips due to electronic equipment power on-offs and thermal excursions. Accelerated thermal cycling is widely employed to strictly examine the electronic products for aerospace usage to simulate the actual thermal environment throughout the service life. In this study, the effect of thermal cycling to mechanical property of Sn-3.0Ag-0.5Cu (SAC305) solder material is investigated by performing three groups of experiments. Essentially, according to the temperature profile measured during a standard temperature cycling (12.5 cycles between -40°C and 60°C lasting for 210 h), two independent groups of experiments are subjected to the extreme low and high dwelling temperatures for 210 h, respectively. Regarding tensile behaviour, the dog-bone type specimens after thermal treatment are tested for at the strain rates of 1×10^-4/s, 5×10^-4/s and 1×10^-4/s. Based on a concise creep-plasticity constitutive model, the thermal effect on solder material property is discussed. The validated constitutive model can be utilized for the predictions of solder property at extreme working conditions with constant or cyclic temperatures.