Infant mortality failures of lead — free solder joints

Two goals of the work - verification of suitability of mechanical tests of solder joints reliability and infant mortality (early failures) of lead-free joints are selected. The results of reliability tests of lead - free solder joints of SMT resistors showed a tendency to increase of infant mortality failure rate comparing to SnPb eutectic joints. These new results are presented. Soldering process parameters, manufacturing equipment, testing methodology and working conditions of lead - free electronic products are discussed and compared to SnPb solder joints technology. Infant mortality and fatigue caused cracks after thermal and mechanical tests are shown in photos and metallographic sections. Statistical results are presented in Weibull plots and failure rate characteristics. Achieved results of primary failures data are presented and discussed. Practical conclusions for manufacturing technology are specified.