The Influence of Bearing Steel Microstructure on Micropitting Resistance: Theory and Experiments
Dr. Predrag Andric
Value for the audience
The audience will get insights about the micropitting as a failure mode in bearings.
Furthermore, the theoretical and experimental results will provide further clarification on the relationship between the steels mechanical properties and micropitting.
Various engineering applications require rolling bearings to operate at very high speeds combined with heavy loads. These demanding conditions can lead to localized sliding between the balls and raceways with sliding speeds up to few m/s, despite the fact that the rolling/sliding ratio is typically low in ball bearings. The combination of high sliding speeds and high contact pressures (up to 3 GPa) can result in localized lubricant film failures and increase the risk of micropitting. This type of failure mode, also known as surface-initiated fatigue at asperity level, can sometimes be initiated by e.g. indentations due to solid particle contamination, among other causes.
In the present study, the influence of steels microstructure and mechanical properties on the micropitting accumulation, has been experimentally and theoretically investigated. The results demonstrate high importance of steel microstructure optimization for high-speed-high-load bearing applications.