Grade: 55CrMnA
Standard: GB / T 1222-1984
● Features and application:
High strength, ductility and toughness, good hardenability, heat-sensitive than the low-manganese steel, high manganese steel than silicon, silicon manganese steel decarburization tendency than the small, temper brittleness. For vehicles, tractors industrial production of heavy load, stress and a larger spring diameter larger coil spring.
● Chemical Composition:
Carbon C: 0.52 ~ 0.60
Si Si: 0.17 ~ 0.37
Manganese Mn: 0.65 ~ 0.95
Sulfur S: ≤ 0.030
Phosphorus P: ≤ 0.030
Chromium Cr: 0.65 ~ 0.95
Ni-Ni: ≤ 0.35
Copper Cu: ≤ 0.25
● Mechanical Properties:
Tensile strength σb (MPa): ≥ 1225 (125)
Conditions yield strength σ0.2 (MPa): ≥ 1978 (110)
Elongation δ5 (%): ≥ 9 (for reference)
Reduction of area ψ (%): ≥ 20
Hardness: hot, ≤ 321HB; cold drawing heat treatment, ≤ 321HB
