【化学成分】(质量分数)(%) 等级 C Mn Si P S V Nb Ti Al Cr Ni
A ≤0.20 1.00~1.60 ≤0.55 ≤0.045 ≤0.045 0.02~0.20 0.015~0.060 0.02~0.20 - ≤0.30 ≤0.70
B ≤0.20 1.00~1.60 ≤0.55 ≤0.040 ≤0.040 0.02~0.20 0.015~0.060 0.02~0.20 - ≤0.30 ≤0.70
C ≤0.20 1.00~1.60 ≤0.55 ≤0.035 ≤0.035 0.02~0.20 0.015~0.060 0.02~0.20 ≥0.015 ≤0.30 ≤0.70
D ≤0.20 1.00~1.60 ≤0.55 ≤0.030 ≤0.030 0.02~0.20 0.015~0.060 0.02~0.20 ≥0.015 ≤0.30 ≤0.70
E ≤0.20 1.00~1.60 ≤0.55 ≤0.025 ≤0.025 0.02~0.20 0.015~0.060 0.02~0.20 ≥0.015 ≤0.30 ≤0.70
【抗拉强度】(σb/MPa) 490~650 【伸长率】(δ5/%) 等级 δ5/%
A ≥19
B ≥19
C ≥20
D ≥20
E ≥20
【屈服点】(σs/MPa) 厚度(直径、边长)/mm ≤16 >16~35 >35~50 >50~100
σs/MPa ≥390 ≥370 ≥350 ≥330