Niobium-containing economical high-plasticity duplex stainless steel with excellent intergranular corrosion resistance and manufacturing method thereof

• Main Authors: WANG HAICHEN, ZHOU QINGLONG, XIAO SHENGYI, JIANG HAIHONG, ZHANG RIHUI, JIANG LAIZHU, XIAO XIANGYONG, KONG QINGMAO, MAO WEIDONG, JIANG YI
• Format: Patent
• Language: Chinese; English
• Published: 13.12.2022
• Subjects: ALLOYS; CHEMICAL SURFACE TREATMENT; CHEMISTRY; CLEANING OR DEGREASING OF METALLIC MATERIAL BY CHEMICALMETHODS OTHER THAN ELECTROLYSIS; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATIONOR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING MATERIAL WITH METALLIC MATERIAL; COATING METALLIC MATERIAL; DIFFUSION TREATMENT OF METALLIC MATERIAL; FERROUS OR NON-FERROUS ALLOYS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUSMETALS OR ALLOYS; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION INGENERAL; MAKING METAL MALLEABLE BY DECARBURISATION, TEMPERING OR OTHERTREATMENTS; METALLURGY; METALLURGY OF IRON; MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; TREATMENT OF ALLOYS OR NON-FERROUS METALS

The niobium-containing economical high-plasticity duplex stainless steel comprises the following components in percentage by mass: 0.01 to 0.06 percent of C, 0.2 to 0.9 percent of Si, 3.0 to 5.0 percent of Mn, 0.8 to 2.0 percent of Ni, 20.6 to 22.5 percent of Cr, less than or equal to 1.0 percent of Mo, less than or equal to 1.0 percent of Cu, 0.08 to 0.15 percent of N, less than 0.07 percent of V, less than 0.04 percent of P, less than 0.0015 percent of S, 0.02 to 0.30 percent of Nb, 0.001 to 0.003 percent of B, 0.01 to 0.03 percent of RE and the balance of Fe and other inevitable impurities. The stainless steel is low in cost, the intergranular corrosion resistance and pitting corrosion resistance of the stainless steel are superior to those of 304 stainless steel, the stress corrosion resistance of the stainless steel is superior to those of 304 austenitic stainless steel and 2205 dual-phase stainless steel at the same time, the room-temperature yield strength Rp0.2 is larger than 500 MPa, the ductility A5