Stress-Strength Interference Model for Structural Reliability under Complex Shock Loads Using Bayesian Estimation

In aerospace engineering, shock loads typically exhibit complex characteristics such as short duration, high magnitude, and a wide frequency range. These loads can easily damage spacecraft electronic components, potentially leading to mission failure. This paper proposes a reliability model based on stress-strength interference, considering the randomness of shock loads, as well as the dispersion in both the shock response spectrum (SRS) and material strength. A Weibull distribution model is used to represent the dispersion of stress and material strength, with the Weibull parameters determined using Bayesian estimation. Next, a crystal oscillator, commonly used in electronic and communication systems, is subjected to a shock experiment to verify the accuracy of the finite element model. The verified model is then subjected to time domain loads synthesized via wavelet analysis. The resulting maximum principal stress data, calculated under varying SRS conditions, are expanded and used for the Bayesian estimation of Weibull parameters. Finally, a stress-strength interference reliability model for electronic components is developed based on the Weibull distribution. This model is validated through reliability experiments on the crystal oscillator under different SRS amplitudes, confirming its feasibility. This method offers a valuable reference for the reliability analysis of spacecraft electronic components.