Fatigue crack nucleation and propagation at clustered metallic carbides in M50 bearing steel. (March 2018)

• Record Type: Journal Article
• Authors: Guan, Jian; Wang, Liqin; Zhang, Zhiqiang; Shi, Xiujiang; Ma, Xinxin
• Is Part Of: Tribology international. Volume 119(2018)
• Page Start: 165
• Page End: 174
• Publication Date: 2018-03
• Subjects: M50 bearing steel -- Metallic carbides -- Crack nucleation -- Crack propagation; Tribology -- Periodicals; 621.89
• DOI: 10.1016/j.triboint.2017.10.016
• Languages: English
• ISSNs: 0301-679X

Abstract

Abstract: This paper focuses on the crack nucleation and crack propagation induced by a cluster of carbides. The morphology of the carbides is extracted from scanning electron microscope images of M50 bearing steel. Subsequently, a continuum damage accumulation model is incorporated into the Voronoi finite element model to investigate the damage evolution in the material. It can be observed that nearly all the micro-cracks nucleate on the boundary of the carbide and propagate through the bearing material matrix around those carbides until they become large enough to coalesce to failure. With the increasing of friction coefficient, cracks gradually grow to the contact surface. The result also shows that the carbides deeper than a certain depth are not harmful to the material. Graphical abstract: Highlights: The morphology of the clustered carbides is extracted and finite element model is built. The damage evolution of M50 bearing steel is studied under 4 lubrication conditions. Higher friction coefficient causes fatigue cracks to extend to contact surface. Carbides located deeper than a certain depth are not harmful to material.