THREE-DIMENSIONAL ANALYSIS OF THERMAL EFFECTS ON SURFACE CRACK PROPAGATION IN ROLLING CONTACT

Abstract

This analysis investigates the thermal effects on crack growth in rolling contact fatigue surface pitting. Here the prepitting crack is modeled as an inclined planar surface crack in a three-dimensional half-space. Rolling contact is simulated as a line load with both normal and shear components, moving with constant velocity over the surface of the half-space. A frictional heat input in the contact region is included to incorporate the thermal loading. The body force method for three-dimensional fracture mechanics is utilized to determine the three modes of stress intensity factors along the crack contour, which quantify crack growth. Numerical results for the stress intensity factors over a loading cycle are given for a semicircular crack. The effects of two thermal parameters, one representing heat input strength and the other representing velocity of the contact region, on the stress intensity factors are determined.