Reliability Analysis of Circuit Board Based on Probability Box Failure Physical Model

This paper focuses on the issue of on-board circuit boards being prone to failure due to environmental factors such as vibration and heat during the actual operation of trains. Finite element simulation is conducted on the actual vibration data of the train, and it is considered that the distribution of heating components on the circuit board is unbalanced, which can lead to the uneven heat distribution of the entire circuit board during operation. Therefore, icepak is used for thermal simulation of the circuit board, using the results of thermal simulation as input for thermal fatigue simulation, the results show that the maximum equivalent stress and equivalent plastic strain are located between the electronic component and the solder joint. In addition, considering the effects of random uncertainty and cognitive uncertainty, a probability box failure physical model for weak components is established to complete reliability analysis at the component level in the circuit board.