Remaining useful life (RUL) estimation of electronic solder joints in rugged environment under random vibration

The remaining useful life (RUL) of electronic modules under the influence of rugged random-vibration and operational conditions is investigated in this paper. The effects of storage conditions and soft failures, caused by the vibrations to solder joints of a printed circuit board (PCB) are analyzed. The RUL is estimated with the help of vibration testing and finite element analysis techniques. Keeping in view the standard and working environmental conditions, the PCB of a power distribution module is subjected to random and sine vibrations. Besides the significance of fatigue damage and RUL estimation of solder joints, caused by storage or operation for a period of five years has not been addressed in existing literature so far. The current study performs the modal analysis to find the natural frequencies, mode shapes, and participation factor ratios of a PCB and its components. These natural frequencies are subsequently verified via comparison with experimental sine sweep results. A random vibration test over the frequency range from 10 Hz to 2000 Hz is also applied for recording the time-to-failure ratio of the PCB. Moreover, the spectrum analysis is performed using the commercial ANSYS software, to assess the acceleration response and the stress power spectral density (PSD) of the critical solder joints. The stress PSD is then used to estimate the random vibration fatigue damage of the solder joint. The calculated fatigue life, based on the modified Miner's rule and the Basquin power-law conform to the actual random vibration testing results.