Keywords

White Etching Area, White Etching Crack, Bearing, Electromagnetics, Current, Cementite, Martensite

Electromagnetic Impact on Early White Itching Cracks in Inhomgeneous Structure of Bearing Steel

White etching cracks (WEC) initially appear under a surface of a bearing at a boundary of propagation of the Hertzian stress [1]. White etching areas (WEA), which are associated with the cracks, found to be harder than the original steel at about 75 HRC [2]. Johnson & Sewell showed that microcracks at a boundary of areas of different hardness can be the origin of the WEA formation [3]. Localized deformations are mentioned as a cause of the WEA, they could initiate a dynamic recrystallization and leave a fine equiaxed structure of nano-scale grains [4]. Such nanostructured material is not etched and is observed to be a white area. An interface of this recrystallized region is not strong and it has been shown that it cracks [5]. Schlicht showed the WEA to be the result of adiabatic shear banding [6].

Authors and Company/Institution

Mihails Ščepanskis and Andris Jakovičs, Laboratory for Mathematical Modelling of Environmental and Technological Processes, University of Latvia, Rīga, Latvia
Imants Kaldre, Institute of Physics of University of Latvia, Salaspils, Latvia

Jānis Maniks, Institute of Solid State Physics of University of Latvia, Rīga, Latvia
Bernard Nacke, Institute of Electrotechnology, Leibniz University of Hanover, Hannover, Germany
Walter Holweger, AG Schaeffler & Co. KG, Herzogenaurach, Germany