X2CrMoTiS18-2 or 1.4523
C: 0.030% max Si: 1.00% max Mn: 0.50% max P: 0.040% max S: 0.15%-0.35% Cr: 17.5%-19.0% Mo: 2.00%-2.50% Ti: 0.30%-0.80% C+N: 0.040% max