Rolling Contact Fatigue of Thrust Ball Bearing under Low Lambda Condition

Abstract

Rolling contact fatigue (RCF) testings of thrust ball bearing under boundary lubrication condition (low lambda condition) are conducted while changing test conditions of load, rotational speed and combination of surface roughnesses for bearing component parts. The RCF test results and measurements of surface roughnesses of before and after the tests show that the raceway surface with larger roughness promotes the surface initiated failure of the other component. In addition, they demonstrate that the behavior of change in surface roughness during rolling contact depends on the test conditions and influences RCF life accordingly. These results suggest that RCF life of rolling bearing used under low lambda conditions should be estimated considering not only analytical relationship between repeated stress in subsurface and surface roughness during RCF, but also experimental database of the running-in behavior depending on RCF conditions.

Keywords

• rolling contact fatigue
• thrust ball bearing
• boundary lubrication
• surface roughness
• running-in
• low lambda