steel JIS SUJ2 Steel: 52100 Equivalent — High-Carbon Chromium Bearing Steel
SUJ2 (JIS G4805) is Japan's 52100-equivalent high-carbon chromium bearing steel — 1.0% C / 1.5% Cr, hardens to 62–65HRC. Full guide: 100Cr6 equivalent, heat treatment, cryogenic processing, and bearing fatigue life.