A mechanistic model for fatigue life prediction of solder joints for electronic packages

Abstract

A mechanistic model for fatigue life prediction of solder joints has been developed. The model utilized fracture mechanics theory using J-integrals and assumed the crack propagation determines the fatigue lifetime of solder joints. The model is expressed in terms of crack length 'a', plastic strain range Delta epsilon(p) and temperature T. Constitutive relation and crack propagation of 62Sn-36Pb-2Ag solder were tested at various temperatures. Good agreement is found between the model and the experimental results. The model has been applied to leadless surface mount solder joints with FEM analysis, which provided the capability of the fatigue life prediction of solder joints of electronic packages under thermal cyclic loading. Copyright (C) 1997 Elsevier Science Limited.