Analytical model to investigate distributions of the thermal stresses in the pad and disk for different temporal profiles of friction power

Abstract

The friction power is a key parameter that largely determines the value and distribution of temperature and corresponding thermal stresses in friction elements of a braking system. In this article, the influence of this parameter on the thermal stresses is under consideration. For this purpose, the exact formula was obtained to determine the normal thermal stresses, arisen due to frictional heating during relative sliding of the pad on the surface of a brake disk, for 10 selected temporal profiles of the specific friction power. Numerical analysis was carried out for a frictional couple consisting of a cast iron disk and a pad made of retinax. It is established that some temporal profiles of the specific friction power can cause the generation of the tensile stresses on the friction surface of a brake disk in a radial direction. The change of compressive stresses into tensile may indicate the initiation of the microcracks on this surface.