Cracks on Bearing Rings III


Structural changes in roller bearing rings resulting in cracks

  Overview of current main mechanisms for the formation of WEA / WEC Copyright: © MSE


Failures are currently being noted in roller bearings long before their calculated fatigue life. These early failures are associated with the occurrence of white etching areas, WEA for short or cracks WEC for short. The formation mechanism is currently described by two basic hypotheses, which are partially contradictory. The causes, governing conditions, and damage progression have not yet been finally clarified.


Research objectives

The objective of this project is to gain an in-depth understanding of WEA / WEC formation in rolling contacts and contribute to clarification of the damage phenomenon. The focus of the project lies in identifying precursors to damage. This should review the current hypotheses on the formation mechanism.
Further partial objectives of the project are:

  • Derivation of limit values for reinforcing factors, particularly compression, slippage, electrical current, and hydrogen
  • Extension of understanding on the effects of reinforcing factors on the processes during WEA / WEC formation
  • Assessment of the suitability of system monitoring based on acoustic emission for the early detection of WEA / WEC formation

Research and project partners

  • Institute for Material Applications in Mechanical Engineering, RWTH Aachen University, IWM
  • Central Facility for Electron Microscopy, RWTH Aachen University, GFE
  Federal Ministry of Economic Affairs and Climate Action Copyright: © BMWK

Promoted by

The Federal Ministry of Economic Affairs and Climate Action

  FVA Logo Copyright: © AIF FVA

Project sponsor

  • Federation of Industrial Cooperative Research Associations, Aif for short
  • Research Association for Drive Technology, FVA for short