牌號質(zhì)量等級化學成分(質(zhì)量分數(shù))/%CSiMnPSVbNBbTibALsaCrCuNiMo

≤

≤

≥

牌號Q235GJB、C0.200.350.60-1.500.0250.015---0.0150.300.300.300.08

D、E0.180.0250.010

Q345GJB、C0.200.55≤1.600.0250.0150.1500.0700.0350.0150.300.300.300.20

D、E0.180.0200.010

Q390GJB、C0.200.55≤1.700.0250.0150.2000.0700.0300.0150.300.300.700.50

D、E0.180.0200.010

Q420GJB、C0.200.55≤1.700.0250.0150.2000.0700.0300.0150.800.301.000.50

D、E0.180.0200.010

Q460GJB、C0.200.55≤1.700.0250.0150.2000.1100.0300.0151.200.501.200.50

D、E0.180.0200.010

Q500GJC0.180.60≤1.800.0250.0150.1200.1100.0300.0151.200.501.200.60

D、E0.0200.010

Q550GJCC0.180.60≤2.000.0250.0150.1200.1100.0300.0151.200.502.000.60

D、E0.0200.010

Q620GJCC0.180.60≤2.000.0250.0150.1200.1100.0300.0151.200.502.000.60

D、E0.0200.010

Q690GJCC0.180.60

≤2.200.0250.0150.1200.1100.0300.0151.200.502.000.60

D、E0.0200.010

a 允許用全鋁含量(Alt)來代替酸溶鋁含量(Als)的要求，此時全鋁含量Alt應不小于0.020％，如果鋼中添加V、Nb或Ti任一種元素，且其含量不低于0.015％時，小鋁含量不適用。

b 當V、Nb、Ti組合加入時，對于Q235GJ、Q345GJ，(V+Nb+Ti)≤0.15％,對于Q390GJ、Q420GJ、Q460GJ,(V+Nb+Ti)≤0.22％。

c 當添加硼時，Q550GJ、Q620GJ、Q690GJ及淬火加回火狀態(tài)鋼中的B≤0.003％。