Contact Behavior of Worn Bearings with Elastoplastic Functionally Graded Coating Based on Mixed Elastohydrodynamic Lubrication

Abstract

The dynamic contact behavior of worn bearings with elastoplastic functionally graded coating is studied, and the interacting effect between worn band and functionally graded surface is analyzed. The surface deformation and roughness are included in the film thickness. The mixed elastohydrodynamic lubrication combined with point contact model is introduced to analyze the oil pressure in the contact zone. By using the Fourier transform method and Papkovich–Neuber potential function, the displacements and stress fields in the elastoplastic functionally graded coating are obtained. The second-order central difference method is used to solve the Reynolds equation. It is found that the repeated surface interaction can result in the sharp increase in pressure in bearings, and the oil pressure increases with increasing graded index. The entrainment of oil in the inlet and outlet zones becomes more evident if a large graded index is selected.