Dynamic Testing of Solder Joint Strength under Compression, Tension and Shearing

Studies on strain rate sensitivity of solder joints at high rates are relatively scarce. This investigation explores the possibility of establishing an experimental technique using a split Hopkinson bar to test single solder specimens. Computational simulation of tests on a cylindrical specimen the size of the solder ball is also performed to validate the assumption of one dimensional wave propagation as well as accuracy of stress-strain data derived. Tests on actual 0.24 mm diameter solder balls show good repeatability of results, confirming the feasibility of applying the SHB technique. Average dynamic stress-strain curves for strain rates ranging from 10²/s to 10³/s were obtained and compared with average responses corresponding to quasi-static strain rates of 10^-3 /s and 1/s for compression, tension and shear loading. Rate sensitivity of the solder ball response is observed.