The fretting wear characteristics of spherical/spherical lateral contacts under different load conditions, contact angles, and the number of fretting cycles are studied. A spherical/spherical lateral fretting wear model is established in ABAQUS software. A UMESHMOTION subroutine for spherical/spherical contact models is written to simulate the fretting wear based on the energy model and the Fortran language. The results show that as the load increases, the contact width increases significantly and the wear depth decreases. It is also found that the rate of change of the wear depth gradually increases in the central portion of the contact area, and is relatively smooth in the contact edge portion. An increase in the magnitude of the moving load causes a small increase in the contact width and a significant increase in the wear depth. The rate of increase of the wear depth at the edge of the contact area gradually increases and the rate of increase of the wear depth at the center of the contact area changes linearly. As the contact angle increases, the contact form gradually changes to a positive contact. Meanwhile, the wear depth variation shifted from a “U” shape to a “W” shape, which caused the wear depth to decrease significantly at the contact center and eventually approach zero as the adhesive area appeared. In addition, with an increase in the number of fretting cycles, the wear depth was almost unchanged at the contact center portion but significantly increased at the edge portion.

Fretting fatigue is a major form of fretting damage affected by various factors. In this paper, the Ruiz parameter is used to predict the variation in the initiation location of the fretting fatigue crack with the amplitude of load, providing a reference for the study of the initiation characteristics of fretting fatigue cracks. The influence of the phase difference between loads is also considered. Three numerical models are established using ABAQUS for simulation experiments. Four phase difference angles are involved, i.e. 0°, 90°, 180° and 270°. Results indicate that for 0° phase difference, the maximum of initiation parameter K is always observed at the trailing edge of the contact zone (near the loading side of the strain load) with the increase of load amplitude, such that the fretting fatigue crack initiates at the trailing edge. However, for 90°, 180°, and 270° phase differences, the maximum of initiation parameter K shifts from one edge of the contact to the other with the increase of load amplitude. In addition, it is observed that the maximum and minimum initiation parameter K values are obtained for 0° and 180° phase differences, respectively, while the values of K for 90° and 270° phase differences are approximately equal and between those for 0° and 180°.