Initiation and propagation of case crushing cracks in rolling contact fatigue

• Published in: Wear Vol. 122; no. 1; pp. 33 - 43
• Main Authors: Leng, Xiaogang, Chen, Qing, Shao, Eryu
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 15.02.1988; Amsterdam Elsevier Science; New York, NY
• Subjects: Applied sciences; crack propagation; Exact sciences and technology; fatigue; Friction, wear, lubrication; Machine components; Mechanical engineering. Machine design; rolling; Fretting fatigue; Wear; Theoretical study; Rolling contact; Scaling; Case hardened steel; Mechanical contact; Experimental study; Crack; Crack propagation
• ISSN: 0043-1648; 1873-2577
• DOI: 10.1016/0043-1648(88)90004-X

The process of development of contact fatigue cracks in case-hardened steel has been recorded by tracing crack propagation drawings. The investigation of the crack propagation drawings has revealed that a spall usually resulted from the coordinated development of a group of cracks, say the leading group of cracks, rather than a single crack. It has also been shown that the development of a leading group of cracks goes through three stages: the incubation period; the stable propagation period; the branching propagation period. The features of the three stages have also been described. The dislocation theory has been used to explain the initiation of contact fatigue cracks. The free beam on an elastic foundation has been applied as a model for analysing the stress state of the location where the branching cracks are initiated.