20CrMnMo hot rolled steel round bars

Good thermal processing performance, normalizing after a good cutting performance, after quenching and tempering with good mechanical properties and low temperature impact toughness, after carburizing have high flexural strength and wear resistance, but poor weldability, to properly warmed up before welding, after welding should be tempered. Commonly used in the manufacturing requirements of high surface hardness, good wear resistance is important carburizing parts, such as gears, camshafts rod, 

Chemical Composition:
Carbon C: 0.17 ~ 0.23
Si Si: 1.17 ~ 1.37
Mn Mn: 0.90 ~ 1.20
Sulfur S: to allow the residual content ≤0.035
Phosphorus P: to allow the residual content ≤0.035
Chromium Cr: 1.10 ~ 1.40
Ni: to allow the residual content ≤0.030
Cu: to allow the residual content ≤0.030
Mo Mo: 0.20 ~ 0.30
Mechanical Properties:
Tensile strength σb (MPa): ≥1175 (120)
Yield strength σs (MPa): ≥885 (90)
Elongation δ5 (%): ≥10
Reduction of ψ (%): ≥45
Impact energy Akv (J): ≥55
Impact toughness αkv (J / cm2): ≥69 (7)
Hardness: ≤217HB
Sample size: Sample size is 15mm rough
Heat treatment and microstructure specifications:
Heat treatment specifications: quenching 850 ℃, oil cooling; tempering 200 ℃, water-cooled, air-cooled.
Microstructure: tempered martensite.
Delivery status: to heat treatment (normalizing, annealing or tempering) or without heat treatment delivery, the delivery status should be specified in the contract.