12CrNi2

Alloy structural steel

Standard: GB / T 3077-1988

Chemical composition
● Chemical Composition:

Carbon C: 0.10 ~ 0.17

Si Si: 0.17 ~ 0.37

Manganese Mn: 0.30 ~ 0.60

Sulfur S: to allow the residual content of ≤ 0.035

Phosphorus P: allow the residual content ≤ 0.035

Chromium Cr: 0.60 ~ 0.90

Ni-Ni: 1.50 ~ 1.90

Copper Cu: to allow the residual content of ≤ 0.030 [1]

Mechanical properties
● Mechanical Properties:

Tensile strength σb (MPa): ≥ 785 (80)

Yield strength σs (MPa): ≥ 590 (60)

Elongation δ5 (%): ≥ 12

Reduction of area ψ (%): ≥ 50

Impact energy Akv (J): ≥ 63

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

Hardness: ≤ 207HB

Sample size: Sample size blank 15mm [2]

● Heat treatment and microstructure specifications:

Standard heat treatment: quenching: the first 860 ℃, the second 780 ℃, water, oil cooling; tempering 200 ℃, water, air-cooled.

● Features Application:

High-hardened steel, quenched and tempered low or high temperature tempering, have good mechanical properties, low temperature impact toughness is good, the notch sensitivity is small, machinability and weldability is still good, but temper brittleness, white points higher sensitivity required for secondary hardening after carburizing, special circumstances need cold treatment. [3]