Probabilistic fatigue damage estimation of embedded electronic solder joints under random vibration

The stress response to random vibrations is an important factor to be taken into account in designing embedded electronic devices. Several test specifications and qualifications use the random vibrations to increase the reliability of electronic products. Fatigue damage estimation of embedded electronic solder joints has not been addressed, especially under random vibration loading. In this paper numerical random vibration analysis with finite element method of an embedded electronic device is used to estimate the stresses Power Spectral Density (PSD). These PSD of stresses are then used in different probabilistic fatigue damage approaches to estimate the reliability of the solder joints regarding the vibration fatigue damage. Two different probabilistic approaches of random fatigue are employed; the time-domain approach based on Rainflow and Monte Carlo simulations and the frequency domain approach based on spectral techniques and statistical data. However, the fatigue damage estimation depends mainly on the accurate results of the stresses PSD. Thus, this work proposes to develop the sub-modelling technique to the random vibration analysis in order to provide accurate results of the stresses PSD. Moreover, this paper discusses the advantages of the approaches listed above to estimate the fatigue damage in solder joints of an electronic component and shows the effectiveness of sub-modelling techniques in the random vibration analysis.