Life Prediction and Damage Acceleration Based on the Power Spectral Density of Random Vibration

Fatigue life prediction and accelerated verification tests under a random vibration environment are important tasks for evaluating product reliability. This paper reviews the characteristics of random stress processes, discusses the methodology of life prediction and accelerated testing under various random loadings by using the stress power spectral density (PSD) function obtained from finite element analysis (FEA), and develops an engineering method to determine the acceleration level and test time in reliability verification tests. The discussions cover the narrow-band Gaussian processes, the wide-band Gaussian processes, and the nonGaussian processes. To illustrate the practical procedure of life prediction and accelerated testing based on the damage equivalent technique, the application example of an automotive component is presented.