Kriterien für Wälzlagerstähle für das Induktionshärten

Abstract

Induction hardening of bearing components offers advantages over other hardening techniques like low energy consumption and connected emissions, superior mechanical properties and the use of low alloyed steel grades. The used steel alloy for induction hardening has a pronounced impact on the hardening result. The dissertation aims at identifying a suitable and robust bearing steel for induction hardening. Based on a literature study, potential bearing steels were selected and compared in terms of heat treatment robustness using a dilatometer. Larger hardness of the prior microstructures as well as low alloyed steel grades were shown to reveal a robust hardening result. The rolling contact fatigue performance was evaluated as one important property of bearing steels. Larger carbon contents or as-heat treated hardness showed superior behavior for classical measures of rolling contact fatigue performance, while lower carbon contents led to smaller and less crack appearance. The roles of different alloying elements, prior austenite grains sizes and residual stresses were discussed. A medium carbon steel was identified as a good compromise revealing a robust heat treatment result and good fatigue performance.