PRECIPITATION HARDENING TYPE STAINLESS STEEL HAVING SATISFACTORY MACHINABILITY AND CORROSION RESISTANCE

摘要

PROBLEM TO BE SOLVED: To provide precipitation hardening type stainless steel which has corrosion resistance and strength required for a marine shaft, a marine pump shaft or the like, also has excellent machinability in a solid solution state.;SOLUTION: The precipitation hardening type stainless steel having satisfactory machinability and corrosion resistance has a composition comprising, by mass, 0.001 to 0.030% C, 0.05 to 1.00% Si, 0.05 to 1.00% Mn, 4.50 to 6.50% Ni, 14.00 to 17.00% Cr, 0.20 to 2.00% Mo, 2.00 to 4.00% Cu, ≤0.05% N, ≤0.010% O, and one or two kinds of metals selected from 0.15 to 0.50% Nb and 0.15 to 0.50% Ti by 0.15 to 0.50% in total, and the balance Fe with inevitable impurities, and also satisfying inequality (1): 0.811[75(14.6-Cr)+110(8.9-Ni)+60(1.33-Mn)+50(0.47-Si)+3000{0.068-(C+N)}-32]-220.8≥100.;COPYRIGHT: (C)2004,JPO