1849 Thermal aging effects on fatigue crack propagation on lead-free solder joints

Metallurgical interactions occur between solders and other materials by means of solid state processes and resulting reaction products (intermetallic compounds, IMC) continue to grow as the solder joint ages. Due to its brittle nature and lattice mismatch, the solder cracks tend to be generated near the intermetallic compounds. Formation of these intermetallic compounds affects the mechanical integrity of solder joints. Therefore, it is important to study the effect of intermetallic compounds development on the mechanical properties of the solder joints. In this paper, we focus on the low cycle fatigue of solder joints and investigate the effects of intermetallic compounds development on the fatigue life and on the fatigue crack growth behavior of solder joints.