Composition: 0.37% to 0.45% carbon, 0.17 to 0.37% silicon, 0.5 to 0.8 manganese, 0.8 to 1.1% chromium
Annealed hardness: less than 207HBS
Normalizing Hardness: less than 250HBS
Quenching: Sample diameter: 25mm, 850-degree quenching oil quenching, tempering after 520 degrees: 1000 MPa tensile yield 800 MPa, elongation 9%, reduction of 45%, impact toughness 588.3 kJ / square m