Alloy structural steel: SNCM439
Standard: JIS G4053-2003
● Chemical Composition:
Carbon C: 0.36 ~ 0.43
Si Si: 0.15 ~ 0.35
Mn Mn: 0.60 ~ 0.90
Sulfur S: allow the residual content ≤0.025
Phosphorus P: to allow the residual content ≤0.025
Chromium Cr: 0.60 ~ 1.00
Ni Ni: 1.60 ~ 2.00
Cu: to allow the residual content ≤0.025
Mo Mo: 0.15 ~ 0.30
● Mechanical Properties:
Tensile strength σb (MPa): ≥980 (100)
Yield strength σs (MPa): ≥835 (85)
Elongation δ5 (%): ≥12
Reduction of area ψ (%): ≥55
Impact energy Akv (J): ≥78
Impact toughness αkv (J / cm2): ≥98 (10)
Hardness: ≤269HB
Sample size: Sample size is 25mm rough
● Heat treatment and microstructure specifications:
Heat treatment specifications: quenching 850 ℃, oil cooling; tempering 600 ℃, water, oil cooling.
● Delivery status: to heat treatment (normalizing, annealing or tempering) or without heat treatment delivery, the delivery status should be specified in the contract.