Damage Mechanisms of Initiating Micro-Pitting on 42CrMo4 Hardened and Tempered Steel


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A deep comprehension of the damage mechanisms involved in contact fatigue should optimize material and heat treatment choice for a specific application. In this work rolling disc-on-disc contact fatigue tests have been performed on a hardened and tempered UNI EN 42CrMo4 . The adopted test method creates the best conditions in order to develop micro-pitting on disc surface. Extensive micro-fractographic examinations have been carried out, on the damaged surfaces, through a scanning electronic microscope (SEM). For this steel, loaded with Hertzian pressure of 1000 MPa, the failure mode is always micro-pitting which begins at the surface, and it is not a sub-superficial damaging. If micro-pits develop, they will coalesce in larger craters. By this way, the probability that micropitting will degenerate into sub-superficial destructive pitting is very high.



Key Engineering Materials (Volumes 348-349)

Edited by:

J. Alfaiate, M.H. Aliabadi, M. Guagliano and L. Susmel




F. D'Errico et al., "Damage Mechanisms of Initiating Micro-Pitting on 42CrMo4 Hardened and Tempered Steel", Key Engineering Materials, Vols. 348-349, pp. 869-872, 2007

Online since:

September 2007




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