Material Name: Alloy structural steel
Grade: 40MnB
Standard: GB / T 3077-1988
● Features and Scope:
With high strength, hardness, wear resistance and good toughness, is a more successful replace 40Cr steel new steel grades. Used as a steering arm on the car, steering knuckle, steering shaft, axle, worm, spline shaft, brake adjustment arm, etc., can also be replaced by a larger section of 40Cr steel parts.
● Chemical Composition:
Carbon C: 0.37 ~ 0.44
Si Si: 0.17 ~ 0.37
Mn Mn: 1.10 ~ 1.40
Sulfur S: to allow the residual content ≤0.35
Phosphorus P: to allow the residual content ≤0.35
Chromium Cr: to allow the residual content ≤0.30
Ni: to allow the residual content ≤0.30
Cu: to allow the residual content ≤0.30
Boron B: 0.0005 ~ 0.0035
● Mechanical Properties:
Tensile strength σb (MPa): ≥980 (100)
Yield strength σs (MPa): ≥785 (80)
Elongation δ5 (%): ≥10
Reduction of ψ (%): ≥45
Impact energy Akv (J): ≥47
Impact toughness αkv (J / cm2): ≥59 (6)
Hardness: ≤207HB
Sample size: Sample size is 25mm rough
● Heat treatment and microstructure specifications:
Heat treatment specifications: quenching 850 ℃, oil cooling; tempering 500 ℃, 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.