sup9a spring steel


Material Name:

● Features and application:
High strength, ductility and toughness, good hardenability, heat-sensitive than the low-manganese steel, silico-manganese steel than high decarburization tendency than Si-Mn steel is small, temper brittleness. For vehicles, tractors industrial production of heavy load, stress and a larger spring diameter larger coil spring.
● Chemical Composition:
C c: 0.56 ~ 0.64
Si si: 0.17 ~ 0.37
Manganese mn: 0.70 ~ 1.00
S s: ≤ 0.030
Phosphorus p: ≤ 0.030
Chromium cr: 0.70 ~ 1.00
Ni-ni: ≤ 0.35
Copper cu: ≤ 0.25
● Mechanical Properties:
Tensile strength σb (mpa): ≥ 1225 (125)
Conditions yield strength σ0.2 (mpa): ≥ 1078 (110)
Elongation δ5 (%): ≥ 9 (for reference)
Reduction of area ψ (%): ≥ 20
Hardness: hot, ≤ 321hb; cold-drawn + heat treatment, ≤ 321hb