C: 0.030%-0.080% Si: 1.00% max Mn: 1.00%-2.00% P: 0.025% max S: 0.015% max Cr: 13.5%-16.0% Mo: 1.00%-1.50% Ni: 24.0%-27.0% Ti: 1.90%-2.30% Alg: 0.35% max B: 0.0030%-0.010% V: 0.10%-0.50%