Structural reliability analysis of automotive parts based on strength degradation and abrasion and correlation

Abstract

In this paper, based on Shcaff residual strength theory, the effect of abrasion is considered while the strength degradation of parts is studied. Based on the maximum abrasion, a stress‐strength interference model considering strength degradation and abrasion is established. Then, the reliability and reliability sensitivity of vehicle parts are analyzed by using the first‐order second moment and random perturbation method, and they are verified by the Monte Carlo method. The fitting results are good. It provides a more practical analysis method for engineering analysis. At the same time, based on the correlation between variables, the effect of correlation coefficient on the reliability of vehicle tension rod is discussed. The reliability index and reliability of the correlation coefficient of vehicle tension rod are analyzed, and the reliability sensitivity of the correlation coefficient is also analyzed. At the same time, the gradient reliability of vehicle tension rod geometry is analyzed based on strength degradation theory. Found that if the influence of multiple correlation coefficients on reliability is increased (decreased), then the influence of parameter correlation on reliability will further increase (decrease). On the contrary, if the influence of multiple correlation coefficients on reliability increases and decreases, the reliability change needs to be analyzed specifically. In other words, the influence of multiple correlation coefficients on reliability will produce superposition effect. It provides a new direction for the study of correlation coefficient.

Modified nonlinear cumulative damage model considering residual strength degradation and gear reliability analysis

“…[11][12] Affected by random factors such as loading, environment, and material attributes, even mechanical parts with high reliability and relatively long service life have decay of reliability characteristics, which is manifested as its strength degradation on the macro level. [13][14] Therefore, the strength degradation law can comprehensively reflect the damage degree of parts, and the residual strength has also become the basis of fatigue life prediction of parts. So far, many scholars have proposed a variety of residual strength degradation theories.…”