Effect of the specimen size in predicting the mechanical properties of PbSn solder alloys

The data obtained from bulk test specimens are often used in deformation models to predict the mechanical response of actual parts that are very different in size and shape, such as solder joints in very large scale integration (VLSI) surface mount components. Such predictions are valid only if the size of the solder joints exceeds the "representative deformation volume" of the bulk specimens, In a previous article, we reported the representative volume of a large Pb-Sn eutectic alloy specimen as a function of applied (uniaxial) tensile strain, and showed that the representative volume was much larger than the size of common surface mount technology (SMT) solder joints, In the present study, the measurement of the representative volume is extended to a single-phase solder alloy (98Pb-2Sn, wt%) deformed in both tension and cyclic loading.