What material is 15CrMo alloy structural steel

15CrMo alloy structural steel is a pearlitic heat-resistant steel with high thermal strength at high temperature（ δ B ≥ 440MPa) and oxidation resistance, and has certain hydrogen corrosion resistance. Due to the high content of Cr, C and other alloy elements in steel, the hardening tendency of steel is obvious and the weldability is poor.

Executive standard of 15CrMo steel plate: GB/T11251.

Chemical composition of 15CrMo alloy structural steel:
Carbon C: 0.12-0.18
Silicon Si: 0.17-0.37
Manganese Mn: 0.40-0.70
Sulfur S: allowable residual content ≤ 0.035
Phosphorus P: allowable residual content ≤ 0.035
Chromium Cr: 0.80-1.10
Nickel Ni: allowable residual content ≤ 0.030
Copper Cu: allowable residual content ≤ 0.030
Mo: 0.40-0.55

Mechanical properties of 15CrMo alloy structural steel:
Tensile strength σ B (MPa): ≥ 440 (45)
Yield strength σ S (MPa): ≥ 295 (30)
Elongation δ 5 (%): ≥ 22
Reduction of area ψ (%): ≥ 60
Impact energy Akv (J): ≥ 94
Impact toughness value α Kv (J/cm2): ≥ 118 (12)
Hardness: ≤ 179HB
Sample size: sample blank size is 30mm

15CrMo alloy structural steel surface quality:
The steel surface shall be free of cracks, folds, scabs, inclusions, laminations and pressed iron oxide scales. Local defects of steel shall be removed, which shall not adversely affect the use of steel, and the minimum allowable size of steel shall be ensured. The width of removal shall not be less than 5 times of the removal depth. Individual small scratches and indentations not exceeding half of the nominal size tolerance calculated from the actual size are allowed.