Bearing steel 100Cr6

100Cr6 is the classic through-hardening bearing steel and the standard material for rings and rolling elements of most rolling bearings. The hypereutectoid chromium steel — the designation indicates roughly one percent carbon with chromium addition — is hardened and tempered, typically reaching about 58–65 HRC. This hardness underpins load capacity in rolling contact, dimensional stability and resistance to indentation. Steel cleanliness is decisive for bearing life, since non-metallic inclusions act as crack initiators for subsurface fatigue; modern vacuum-treated melts have raised achievable life considerably. Its limits are corrosion and elevated temperature — stainless or hybrid bearings serve those applications.