Abstract
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.
Publisher
Trans Tech Publications, Ltd.
Subject
Mechanical Engineering,Mechanics of Materials,General Materials Science
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