NEUTRAL CHLORIDE CORROSION RESISTANT AUSTENITIC STAINLESS STEEL

• Main Authors: TARUYA YOSHIO, HASHIZUME HISANOBU
• Format: Patent
• Language: English
• Published: 08.09.1998
• Edition: 6
• Subjects: ALLOYS; CHEMISTRY; FERROUS OR NON-FERROUS ALLOYS; METALLURGY; TREATMENT OF ALLOYS OR NON-FERROUS METALS

PROBLEM TO BE SOLVED: To provide an austenitic stainless steel having excellent crevice corrosion resistance and stress corrosion cracking resistance in a neutral chloride environment and furthermore excellent in sulfuric acid dew point corrosion- resistance and hot workability. SOLUTION: This stainless steel has a compsn. contg., by weight, <=0.05% C, <=1% Si, <=2% Mn, <=0.03% P, <=0.01% S, 18 to 24% Cr, 16 to 26% Ni, 4 to 6.5% Mo, 0.1 to 0.3% N, 0 to 3.0% Cu, 0 to 3.0% W, 0 to 0.05% Al, 0 to 0.005% Ca, 0 to 0.005% Mg and 0 to 0.002% B, in which PI value and Ni-bal. value shown by the formulae I and II satisfy 35<=PI<=50 and -2.5<=Ni-bal.<=1, and the balance Fe with inevitable impurities. The formula I is PI=Cr+3.3(Mo+0.5W)+16N and the formula II is Ni-bal.=Ni+30(C+N)+0.5Mn-1.1(Cr+1.5Si+Mo), where the elemental symbols in each formula denote the weight% of each element in the steel.