Material Name: Alloy structural steel Grade: 18Cr2Ni4WA Standard: GB / T 3077-1988 ● Chemical Composition: Carbon C: 0.13 ~ 0.19 Si Si: 0.17 ~ 0.37 Mn Mn: 0.30 ~ 0.60 Sulfur S: allow the residual content ≤0.025 Phosphorus P: to allow the residual content ≤0.025 Chromium Cr: 1.35 ~ 1.65 Ni Ni: 4.00 ~ 4.50 Cu: to allow the residual content ≤0.025 Tungsten W: 0.80 ~ 1.20 ● Mechanical Properties: Tensile strength σb (MPa): ≥1175 (120) Yield strength σs (MPa): ≥835 (85) Elongation δ5 (%): ≥10 Reduction of ψ (%): ≥45 Impact energy Akv (J): ≥78 Impact toughness αkv (J / cm2): ≥98 (10) Hardness: ≤269HB Sample size: Sample size is 15mm rough ● Heat treatment and microstructure specifications: Heat treatment specifications: quenching: the first 950 ℃, the second time 850 ℃, air cooling; tempering 200 ℃, water-cooled, air-cooled. ● Delivery status: to heat treatment (normalizing, annealing or tempering) or without heat treatment delivery, the delivery status should be specified in the contract. |