40CrV, alloy structural steel. Unified digital code: A23402.

Standard: GB / T 3077-1988

Chemical composition
Mass fraction (%):

Carbon C: 0.37 ~ 0.44

Si Si: 0.17 ~ 0.37

Manganese Mn: 0.50 ~ 0.80

Sulfur S: to allow the residual content of ≤ 0.035

Phosphorus P: allow the residual content ≤ 0.035

Chromium Cr: 0.80 ~ 1.10

Ni: to allow the residual content of ≤ 0.030

Copper Cu: to allow the residual content ≤ 0.030

Vanadium V: 0.10 ~ 0.20

Mechanical properties
Sample size [blank]

25mm

[Specification] heat treatment

Quenching 880 ℃, oil cooling; tempering 650 ℃, water-cooled, oil-cooling.

[Mechanical properties]

Tensile strength σb (MPa): ≥ 885 (90)

Yield strength σs (MPa): ≥ 735 (75)

Elongation δ5 (%): ≥ 10

Reduction of area ψ (%): ≥ 50

Impact energy Akv (J): ≥ 71

Impact toughness αkv (J/cm2): ≥ 88 (9)

Brinell hardness (HBS100/3000) (annealing or tempering condition): ≦ 241