MARTENSITIC STAINLESS STEEL

• Main Authors: AMAYA, HISASHI, KONDO, KUNIO
• Format: Patent
• Language: English; French
• Published: 27.01.2005
• Subjects: ALLOYS; CHEMISTRY; FERROUS OR NON-FERROUS ALLOYS; METALLURGY; TREATMENT OF ALLOYS OR NON-FERROUS METALS

A martensitic stainless steel which has a essential chemical composition, in mass %, wherein C: 0.001 to 0.1 %, Si: 0.05 to 1.0 %, Mn: 0.05 to 2.0 %, P: 0.025 % or less, S: 0.010 % or less, Cr: 11 to 18 %, Ni: 1.5 to 10 %, sol.Al : 0.001 to 0.1 %, N: 0.1 % or less, O: 0.01 % or less, Cu: 0 to 5 %, and Mo forming a solid solution: 3.5 to 7 %, wherein the following formula (1) is satisfied and optionally one or more elements selected from at least one gro up of the following A to C groups are further contained, and wherein the balanc e is composed of Fe, Mo forming no solid solution, if any, and impurities, formula (1): Ni-bal.= 30(C+N)+0.5(Mn+Cu)+Ni+8.2 -1.1(Cr+Mo+1.5Si) >= -4.5 ; A group - W: 0.2 to 5 %, B group - V: 0.001 to 0.50 %, Nb: 0.001 to 0.50 %, Ti : 0.001 to 0.50 % and Zr: 0.001 to 0.50 %, C group - Ca: 0.0005 to 0.05 %, Mg: 0.0005 to 0.05 %, REM: 0.0005 to 0.05 % and B: 0.0001 to 0.01 %. The martensitic stainless steel has the resistance to sulfide stress corrosion cracking being superior to that of super 13 Cr steel and exhibits the streng th and corrosion resistance comparable to those of duplex stainless steel.</SDO AB>