Alloy structural steel: 8620 Standard: ASTM A29 / A29M-04 ● Chemical Composition: Carbon C: 0.18 ~ 0.23 Si Si: 0.15 ~ 0.35 Mn Mn: 0.70 ~ 0.90 Sulfur S: to allow the residual content ≤0.035 Phosphorus P: to allow the residual content ≤0.035 Chromium Cr: 0.40 ~ 0.60 Ni Ni: 0.40 ~ 0.70 Cu: to allow the residual content ≤0.030 Mo Mo: 0.15 ~ 0.25 ● Mechanical Properties: Tensile strength σb (MPa): ≥980 (100) Yield strength σs (MPa): ≥785 (80) Elongation δ5 (%): ≥9 Reduction of area ψ (%): ≥40 Impact energy Akv (J): ≥47 Impact toughness αkv (J / cm2): ≥59 (6) Hardness: ≤197HB Sample size: Sample size is 15mm rough ● Heat treatment and microstructure specifications: Heat treatment specifications: quenching 850 ℃, oil cooling; tempering 200 ℃, air cooling. ● Delivery status: to heat treatment (normalizing, annealing or tempering) or without heat treatment delivery, the delivery status should be specified in the contract. |