Rolling Contact Fatigue Life and Categorization of Failure in Experiment of Flat PEEK Race-Alumina Ball Bearings in Water Lubrication under 1700 N at 1000 rpm

The rolling contact fatigue tests of flat polyether-ether-ketone (PEEK) race-alumina balls bearings in water lubrication were done. From the experiments under 1700 N at 1000 rpm, three types of failures were obtained: a crater-shaped flaking, a rhombus-shaped flaking and a large cracking failures. To research the relationships between the failures and the lives, the surface properties near the failures were measured and observed. No relationships between the surface roughness and the life were found. On the other hand, the contact width of the shorter life specimen was larger than that of the longer life specimen. Two types of the flaking holes were compared to study the differences. The crater-shaped flaking hole exceeded the contact track, but the rhombus-shaped flaking hole existed inside the contact track. In addition, the crater-shaped flaking hole was shallower than the rhombus-shaped flaking hole. This means that the flaking mechanisms were different between them, i. e. the differences of the flaking mechanisms caused the differences of the life.