Advanced FE model for simulation of pitting crack growth

Abstract

An advance parametric FEA model for simulation of pitting arise phenomena on the gear teeth is presented in this article. The assumption of the developed computational approach was that pitting (pits on the contact surfaces) is a result of fatigue crack propagation under (rolling) contact loading conditions. Developed crack growth laws (based on the Paris law) allow to perform simulations of pitting crack growth with respect to the non-proportional and non-linear nature of loading of pitting crack tip, which result from specific loading condition. Specific crack tip loading and pitting crack growth was evaluated using the J-integral criterion of fracture mechanics. Advance model of penetration of the fluid lubricant into fatigue (pitting) cracks was designed using special hydrostatic fluid finite elements, which allow to include the closure of pressured lubricant between fracture surfaces during the simulation of gearing meshing. A simplified distribution of residual stresses in the surface layers of teeth is included as well. The simulations were carried out under the commercial code ABAQUS CAE FEM programme which allows to develop in-house codes using the Python scripting language and user subroutines. Mentioned programme codes and user subroutines are the basis of all FEA including the simulation of the specific loading conditions of pitting crack tip and the incremental pitting crack growth. Wide sensitivity study of the influence of selected model parameters was carried out. Achieved results – final pitting crack shapes and time needed for their formation were compared with experimental results.