Comparison of fatigue performances of 32CrMoV13 and M50 steels in presence of surface indents
Résumé
The fatigue resistance of 32CrMoV13 nitrided steel in the presence of controlled surface indents is investigated in comparison with M50 reference steel. For that purpose, rolling contact fatigue tests have been performed on a two-disk machine under pure rolling and rolling plus sliding conditions. Artificial indents are produced by using a hardness machine equipped with spherical diamond tips of different radii. The overall set of data shows better performances for 32CrMoV13 nitrided steel. The specific properties of this steel are highlighted by microstructural observations. The results are discussed in terms of endurance limit in presence of indents. The hierarchy of theoretical harmfulness thus obtained for the various indents tested in this work agrees well with that observed experimentally.