Tensile Behaviors of Lead-Containing and Lead-Free Solders at High Strain Rates

Abstract

Behavior of solder joints in microelectronic packages is crucial to the drop impact reliability design of mobile electronic products. In this paper, tensile behaviors of Sn37Pb, Sn3.5Ag, and Sn3.0Ag0.5Cu at strain rates of 600 s−1, 1200 s−1, and 1800 s−1 were investigated using the split Hopkinson tensile bar experimental technique. Stress-strain curves of the three solders were obtained, and microstructure and fractography of the specimens before and after the tests were examined and presented. The experimental results show that the lead-free solders are strongly strain rate dependent: Their tensile strength, percent elongation, and percent reduction in area are much greater than those properties of the lead-containing solder at high strain rates.