Research and analysis on visualization and measurement of stress distribution in sliding friction pair

This article investigates the stress distribution characteristics of a sliding friction pair during the contact process using photoelastic experimental technology. The friction pair is simplified to a plane stress state, and an improved photoelastic experimental device is employed to obtain interference fringe images under various operating conditions. The dynamic evolution of the stress field from a static state to sliding conditions is analyzed. The experimental results indicate that as the driving force increases until sliding occurs, the contact pressure becomes significantly concentrated toward the leading edge of the motion. Furthermore, the actual pressure distribution deviates markedly from the theoretically assumed linear distribution, particularly at the contact edges. Utilizing an inversion method, it was determined that the actual pressure distribution on the surface of the slider more closely resembles a quadratic curve. Furthermore, the distribution of shear stress at specified points under a given load has been examined. In the absence of friction, the numerical simulations align closely with experimental data regarding the principal stress difference. However, when friction is present, significant discrepancies arise between the two, indicating that the theoretical pressure distribution model fails to accurately represent the contact state under actual working conditions. Finally, the influence of the coefficient of friction and the position of the driving force on the contact pressure is analyzed. This study provides a theoretical basis for the revision of friction pair models and facilitates more precise component design.