28Mn6 or 1.1170
C: 0.25%-0.32% Si: 0.40% max Mn: 1.30%-1.65% P: 0.035% max S: 0.035% max Cr: 0.40% max Mo: 0.10% max Ni: 0.40% max Cr+Mo+Ni: 0.63% max