C: 0.070% max Si: 0.70% max Mn: 1.00% max P: 0.040% max S: 0.015% max Cr: 13.0%-15.0% Mo: 1.20%-2.00% Ni: 5.00%-6.00% Nb: 0.15%-0.60% Cu: 1.20%-2.00%