The welding process null which prevents the ductile decrease crack of the ferritic stainless steel

摘要

PROBLEM TO BE SOLVED: To prevent generation of ductile fracture with excellent reproducibility, in welding ferritic stainless steel. ;SOLUTION: In welding a ferritic stainless steel which contains, in mass percentage 0.03% or less C, 2.0% or less Si, 2.0% or less Mn, 5.0-30.0% Cr, and 0.03% or less N, and which contains one or more kind of 0.05-1.0% Nb, 0.05-1.0% Ti, 0.05-3.0 Mo, and 0.02-1.0% Cu, with the balance Fe and impurities, the highest achievable temperature on the rear of a weld zone during welding is set lower than the melting point of that steel by 100°C or more, and also, the penetration ratio (%) defined in the following equation is set in the range of 20-80%: penetration ratio (%) = penetration depth/thickness of base stock to be welded × 100.;COPYRIGHT: (C)1997,JPO