Numerical simulation of the surface fatigue crack growth on gear teeth flanks

The paper describes a two-dimensional computational model for simulation of the surface-initiated fatigue-crack growth in the contact area of gear-teeth flanks. The discretised model of gear teeth is subjected to normal loading (Hertzian contact pressure), tangential loading (friction between gear-teeth flanks) and additional external contact forces that arise from the EHD-lubrication conditions. The J-integral method in the framework of the finite-element analysis is used for the simulation of the fatigue-crack propagation from the initial to the critical crack length, when the material's surface layer breaks away and a pit appears on the surface. The comparison of computational and experimental results shows that the proposed model reliably simulates the surface-fatigue crack growth under contact loading and can be used for computational predictions of surface pitting for various contacting mechanical elements like gears, bearings, wheels, etc. (C) 2000 Journal of Mechanical Engineering. All rights reserved.