| 摘要 |
PURPOSE:To prevent the occurrence of creep damage in a ferritic steel by specifying the composition of a ferritic steel at the time of producing a welded joint by joining and welding an austenitic stainless steel and a ferritic steel. CONSTITUTION:At the time of producing a welded joint by joining and welding an austenitic stainless steel to a ferritic steel, a ferritic steel having a composition containing, by weight, 0.03-0.12% C, <=0.70% Si, 0.10-1.50% Mn, <=0030% P, <=0.015% S, 1.50-3.50% Cr, <=0.40% Mo, 1.00-3.00% W, 0.10-0.35% V, 0.01-0.10% Nb, <=0.030% sol.Al, <=0.020% B, and <=0.30% N is used. At this time, a Y309 or 'Inconel (R)' type material is used as a welding material. By this method, the occurrence of creep or creep fatigue crack, due to thermal stress, on the ferritic steel side can be prevented, and the service life of a welded joint can be prolonged. |
