Melting route effects on the rotatory bending fatigue and rolling contact fatigue properties of high carbon bearing steel SAE52100

•Three melting and refining routes are applied to produce GCr15 bearing steels.•The majority of RBF failure originates from subsurface brittle inclusions.•Both RCF-life and RBF-strength are strongly dependent on the inclusion size.•No RCF failures occur when the critical inclusion size is smaller than 16 μm. The rotatory bending fatigue (RBF) behavior, the rolling contact fatigue (RCF) behavior and inclusion characteristics are examined on SAE52100 steels fabricated by three different melting routes. It is found that both RCF-life and RBF-strength are strongly determined by the inclusion size and no RCF could be found when the maximum inclusion size is smaller than 16 μm, which is strongly dependent on the melting routes. This conclusion is not only very important to control of the characteristics of non-metallic inclusions but to the adjustment and improvement of processing techniques of SAE52100 bearing steels in the steel industry.