30号钢化学成分:含碳(C)0.27~0.34,锰(Mn)0.50~0.80,镍(Ni)≤0.30,硅(Si)0.17~0.37,磷(P)≤0.035,硫(S)≤0.035,铬(Cr)≤0.25,铜(Cu)≤0.25