HIGH-GRADE DUPLEX STAINLESS STEEL WITH MUCH SUPPRESSED FORMATION OF INTERMETALLIC PHASES AND HAVING EXCELLENT CORROSION RESISTANCE, EMBRITTLEMENT RESISTANCE, CASTABILITY AND HOT WORKABILITY

摘要

PROBLEM TO BE SOLVED: To provide high-grade duplex stainless steel having an excellent corrosion resistance, embrittlement resistance, castability and hot workability.;SOLUTION: The high-grade duplex stainless steel has a chemical composition consisting, by weight, of 21.0-38.0% Cr, 3.0-12.0% Ni, 1.5-6.5% Mo, 0-6.5% W, 3.0% or less Si, 1.0% or less Al, 8.0% or less Mn, 0.2-0.7% N, 0.1% or less C, at least one element selected from the group consisting of 0.1% or less B, 3.0% or less Cu and 3.0% or less Co, and Mischmetal (MM) and/or 0.0001-1.0% Y in total, and the balance of iron and inevitable impurities. Formation of intermetallic phases such as sigma (σ) and khi (χ) deteriorating corrosion resistance and mechanical properties is suppressed.;COPYRIGHT: (C)2011,JPO&INPIT