Thermal Fatigue of a Surface Mount Resistor
Application ID: 16083
A surface mount resistor is subjected to thermal cycling. The difference in the thermal expansion of different materials will introduce stresses in the structure. The solder which connects the resistor with the printed circuit board is seen as the weakest link in the assembly. It responds nonlinearly to changes in both temperature and time. In order to ensure the structural integrity of the component two fatigue analyses are performed. The first one predicts life based on the inelastic strain following a Coffin-Manson type model and the second uses the dissipated creep energy in the fatigue formulation.