Review of Recent Developments in Understanding Rolling Bearing and Transmission Steel Steelmaking and Hydrogen Effects

Abstract

Rolling contact fatigue life in rolling bearings and transmission components is strongly affected by metallurgical cleanliness and other parameters. Special steel quality has significantly improved over the past decades. Nonmetallic inclusions heavily influence contact fatigue life, and researchers have shown that different inclusion types can exist depending on the applied steelmaking technologies. It is important to recognize the importance of inclusion-matrix bonding. Some types are more susceptible to debonding, which influences contact fatigue strength. Debonded inclusions are internal stress concentrations and can initiate contact (and structural) fatigue failure if above a critical size. Hydrogen is trapped in microcavities in the microstructure. This paper reviews this effect for 52100 and carbon steels and discusses the relevance of hydrogen traps.