Mechanical properties:
Tensile strength σb (MPa): ≥ 450
Conditions yield strength σ0.2 (MPa): ≥ 205
Elongation δ5 (%): ≥ 22
Reduction of area ψ (%): ≥ 50
Hardness: ≤ 183HB
Heat treatment specifications: air-cooled 680 ~ 820 ℃ annealing or slow cooling.
Microstructure: Organizing for the ferrite.
Chemical Composition (%):
C: ≤ 0.12
Si: ≤ 1.00
Mn: ≤ 1.25
P: ≤ 0.060
S: ≤ 0.015 (in GB/T1220-2007 in, S ≥ 0.015)
Cr: 16.00 ~ 18.00
Mo: ≤ 0.60
Ni: ≤ 0.60
