65Mn spring steel

Standard: GB / T 1222-1984
● Features and application:
65Mn spring steel, manganese improve hardenability, φ12mm the hardenability of steel oil can, a small surface decarburization tendency than silicon, the mechanical properties after heat treatment is better than carbon steel, but overheating sensitivity and temper brittleness. As small size of flat, round spring, spring seat, spring winding, spring ring can also be produced, valve springs, clutch springs, brake springs and cold drawn steel wire cold roll coil spring.
● Chemical Composition:
Carbon C: 0.62 ~ 0.70
Si Si: 0.17 ~ 0.37
Manganese Mn: 0.90 ~ 1.20
Sulfur S: ≤ 0.035
Phosphorus P: ≤ 0.035
Chromium Cr: ≤ 0.25
Ni-Ni: ≤ 0.25
Copper Cu: ≤ 0.25
● Mechanical Properties:
Tensile strength σb (MPa): ≥ 980 (100)
Yield strength σs (MPa): ≥ 784 (80)
Elongation δ10 (%): ≥ 8
Reduction of area ψ (%): ≥ 30
Hardness: hot, ≤ 302HB; cold-drawn + heat treatment, ≤ 321HB