THE INFLUENCE OF CRACK-FACE FLUID PRESSURE ON THE FATIGUE CRACK PROPAGATION DUE TO ROLLING CONTACT WITH FRICTIONAL HEAT

Abstract

A three-dimensional surface planar crack problem in a half-space is considered under rolling/sliding contact with frictional heat and hydraulic pressure by the entrapped fluid within the crack. 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. The body force method for three-dimensional fracture mechanics is utilized to determine the three modes of stress intensity factors along the crack contour. To account for mixed-mode propagation, the modified Paris power law is used. Numerical results for the stress intensity factors and the simulations of fatigue crack propagation are given for 30-degree inclined planar surface cracks of semicircular shape. The effects of the frictional coefficient, sliding/rolling ratio, and the crack-face fluid pressure on the crack propagation life are considered for a high carbon-chromium bearing steel.