High-strength welded steel structures having excellent corrosion resistance

摘要

PCT No. PCT/JP96/02834 Sec. 371 Date Mar. 25, 1998 Sec. 102(e) Date Mar. 25, 1998 PCT Filed Sep. 27, 1996 PCT Pub. No. WO97/12072 PCT Pub. Date Apr. 3, 1997Welded high-strength steel structure with excellent SSC and corrosion resistance in a wet carbon dioxide environment having a low H2S concentration. A structure having a Vickers hardness of at most 350 and a joint tensile strength of at least 620 MPa and composed of a base metal comprising a martensitic stainless steel with a martensitic or tempered martensitic structure containing 0.001 to 0.05% C and 9 to 14% Cr and a weld metal comprising an austenitic-ferritic stainless steel having a duplex structure composed of austenite and 35 to 75% by volume of ferrite and containing 22 to 27% Cr,7 to 11% Ni and 1.5 to 5% Mo, and at most 0.03% C as an impurity.