Properties and parameters of 40CrMo alloy steel

40CrMo alloy steel has high strength, hardenability, good toughness, small deformation during quenching, and high creep strength and endurance strength at high temperatures.

40CrMo alloy steel is used for manufacturing forgings that require higher strength and larger quenched and tempered sections than 35CrMo steel, such as large gears for locomotive traction, booster transmission gears, rear axles, connecting rods and spring clips that are heavily loaded, and can also be used for oil deep well drill pipe joints and fishing tools below 2000m.

Chemical composition of 40CrMo steel:
C: 0.35-0.45
Si: 0.15-0.40
Mn: 0.40-0.70
P: <=0.035
S: <=0.035
Cr: 1.00-1.50
Mo: 0.15-0.25

Mechanical properties of 40CrMo alloy steel:
Tensile strength σb (MPa): ≥1080(110)
Yield strength σs (MPa): ≥930(95)
Elongation δ5 (%): ≥12
Reduction of area ψ (%): ≥45
Impact energy Akv (J): ≥ 63
Impact toughness value αkv (J/cm2): ≥78(8)
Hardness: ≤ 217HB
Sample size: The size of the sample blank is 25mm

40CrMo alloy steel metallographic structure: tempered sorbite
Heat treatment specification for 40CrMo steel: quenched at 850℃, oil cooled; Tempered at 560℃, water cooled, oil cooled.

40CrMo alloy steel delivery status: delivered in heat treated (normalized, annealed, or high-temperature tempered) or non heat treated state, and the delivery status should be specified in the contract.