Chemical composition of 780M40 alloy steel

780M40 Chemical composition:

Carbon C: 0.38 ~ 0.43

Silicon Si: 0.15 ~ 0.35

Manganese Mn: 0.75 to 1.00

Sulfur S: ≤0.040

P: ≤0.030

Chromium: 0.80 ~ 1.10

Nickel Ni: ≤0.030

Copper: ≤0.030

Molybdenum Mo: 0.15 ~ 0.25

780M40 Mechanical properties:

Tensile strength σb (MPa) : ≥1080(110)

Yield strength σs (MPa) : ≥930(95)

Elongation δ5 () : ≥12

Section shrinkage ratio ψ () : ≥45

Impact power Akv (J) : ≥63

Impact toughness value αkv (J/cm2) : ≥78(8)

Hardness: ≤217HB