Numerical simulation of surface pitting due to contact loading

A two-dimensional computational model for simulation of surface pitting of mechanical elements subjected to contact loading conditions is presented. I n the model it is assumed the initial crack of length 0.015 mm is initiated at the contacting surfaces due to previously thermal or mechanical treatme nt of the material. The discretised model with the initial crack is then su bjected to normal contact pressure, which takes into account the EHD-lubric ation conditions, and tangential loading due to friction between contacting surfaces. The model accounts also for the influence of fluid trapped in th e crack on crack propagation. The virtual crack extension (VCE) method in t he framework of finite element analysis is then used for two-dimensional si mulation of fatigue crack propagation under contact loading from the initia l crack up to the formation of the surface pit. The pit shapes and relation ships between the stress intensity factor and crack length are determined f or various combinations of contacting surface curvatures and loadings. The comparison of computational and available experimental results shows that t he proposed model reliably simulates the surface fatigue crack growth under contact loading and can be used for computational predictions of surface p itting for various contacting mechanical elements. (C) 2001 Elsevier Scienc e Ltd. All rights reserved.