Q235分A、B、C、D四级(GB700-88)Q235A级含C0.14~0.22% Mn0.30~0.65Si≤0.30S≤0.050P≤0.045Q235B级含C0.12~0.20% Mn0.30~0.670Si≤0.30S≤0.045P≤0.045Q235C级含C≤0.18% Mn0.35~0.80Si≤0.30S≤0.040P≤0.040Q235...