12CrMoV, alloy structural steel. Unified digital code: A31122

Standard: GB / T 3077-1988

[1] [chemical composition] (wt) (%)

Carbon C: 0.08 ~ 0.15

Si Si: 0.17 ~ 0.37

Manganese Mn: 0.40 ~ 0.70

Sulfur S: to allow the residual content of ≤ 0.035

Phosphorus P: allow the residual content ≤ 0.035

Chromium Cr: 0.30 ~ 0.60

Ni: to allow the residual content of ≤ 0.030

Copper Cu: to allow the residual content ≤ 0.030

Vanadium V: 0.15 ~ 0.30

Mo Mo: 0.25 ~ 0.35

[2] [Mechanical properties]

Blank sample size (mm): 30

Heat treatment:

The first quenching temperature (℃): 970; coolant: air

Second quenching temperature (℃): -

Tempering heating temperature (℃): 750; coolant: air

Tensile strength σb (MPa): ≥ 440 (45)

Yield strength σs (MPa): ≥ 225 (23)

Elongation δ5 (%): ≥ 22

Reduction of area ψ (%): ≥ 50

Impact energy Akv (J): ≥ 78

Impact toughness αkv (J/cm2): ≥ 98 (10)

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

Delivery status: to heat treatment (normalizing, annealing, or tempering) or heat treatment delivery, delivery status should be indicated in the contract.

[Main features]

This is a type of heat-resistant pearlitic steel, long-term use at high temperatures when the organization has a high thermal stability and strong resistance, heat treatment thermal sensitivity is low, no tendency to temper brittleness; steel, plastic deformation in the cold high, cutting good; welding in general, but the wall thickness of parts to be heated to 200 ~ 300 ℃, after welding, in addition to stress the need for treatment. This steel is usually tempered at high temperature and high temperature normalizing the state to use, the use of temperature -40 ~ 560 ℃.