Multiaxial low cycle fatigue damage of a lead-free solder Sn-8Zn-3Bi under non-proportional
loading was evaluated. In non-proportional loading tests, a larger number of cracks were
observed on the specimen surface compared to the proportional loading tests, and their
directions were diverse due to direction change in stress and strain. In the circle loading test
in which axial and shear strain have a 90° phase difference, the number of cracks rose from
very early stage of the fatigue life, and their increasing rates were higher than those in a …