EN 30CrNiMo8: High-Hardenability Quenched & Tempered Steel

EN 10083-3 · Published: 2026-06-01 · Updated: 2026-06-02

Quick Reference

EN 30CrNiMo8 (1.6580) is a medium-carbon nickel-chromium-molybdenum steel with 0.26-0.34% C, 1.80-2.20% Ni, 1.80-2.20% Cr, and 0.30-0.50% Mo—providing through-hardening capability in sections up to 200 mm. This deep hardenability combined with...

EN 30CrNiMo8 (1.6580) is a medium-carbon nickel-chromium-molybdenum steel with 0.26-0.34% C, 1.80-2.20% Ni, 1.80-2.20% Cr, and 0.30-0.50% Mo—providing through-hardening capability in sections up to 200 mm. This deep hardenability combined with excellent low-temperature toughness makes it the preferred material for large forged shafts, generator rotors, marine propeller shafts, and heavy-duty gear blanks in European heavy machinery. The higher nickel content compared to 34CrNiMo6 (4340) gives 30CrNiMo8 the edge for very large sections where the core must achieve uniform properties. Available in forged bars up to 800 mm diameter from specialized mills.

Quick Facts

CategoryAlloy Steel
StandardEN 10083-3
Density7.85 g/cm³
Yield Strength850 MPa (123 ksi) Q&T
Tensile Strength1,000 MPa (145 ksi) Q&T

Global Equivalents & Cross-Reference

Alternative Standard / GradeAction
DIN 1.6580 Compare
AISI 4340 (similar) Compare
SNCM431 Compare
30CrNiMo8 Compare

Related Materials

🧮 Material Weight Calculator

Calculate the weight based on this material's density: 7.85 g/cm³

Frequently Asked Questions

Can 30CrNiMo8 be nitrided?

Yes, 30CrNiMo8 responds well to gas nitriding at 500-530°C for 30-60 hours, producing a 0.3-0.6 mm deep hardened case with 900-1,100 HV surface hardness. The chromium content ensures good nitride case formation. Nitriding is applied to large shafts and gears where the core is Q&T to 850-1,000 MPa and the nitrided surface provides wear resistance without the distortion of carburizing. For maximum fatigue strength improvement, liquid (salt bath) nitrocarburizing is also effective.

References & International Standards

  • ASTM International. Standard Specifications for Steel & Metal Alloys. astm.org
  • International Organization for Standardization (ISO). Metallic Materials — Cross-Reference Database. iso.org
  • American Iron and Steel Institute (AISI). Steel Grade Designations & Equivalents. steel.org
  • European Committee for Standardization (CEN). EN Steel Standards & Numbering System. cencenelec.eu