FERRITIC STAINLESS STEEL WELDED STRUCTURE AND METHOD FOR MANUFACTURING THE SAME, WELDING MATERIAL, AND EXHAUST HEAT RECOVERY DEVICE

• Main Authors: TAI ZENICHI, FUJIMURA YOSHIYUKI
• Format: Patent
• Language: English; Japanese
• Published: 03.04.2023
• Subjects: ALLOYS; CHEMISTRY; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; FERROUS OR NON-FERROUS ALLOYS; MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR; METALLURGY; PERFORMING OPERATIONS; SOLDERING OR UNSOLDERING; TRANSPORTING; TREATMENT OF ALLOYS OR NON-FERROUS METALS; WELDING; WORKING BY LASER BEAM

To provide a ferritic stainless steel welded structure which is excellent in corrosion resistance and heat resistance, especially, corrosion resistance and heat resistance of a weld metal part.SOLUTION: A ferritic stainless steel welded structure includes a base material and a weld metal part. The base material has a composition which consists of, by mass, 0.100% or less C, 1.00% or less Mn, 1.00% or less Ni, 0.100% or less P, 0.050% or less S, 15.00-24.00% Cr, 0.100% or less N, 1.00% or less Cu, 1.00% or less Mo, 3.00% or less Si, 0.80-5.00% Al, 0.50% or less Nb, and 0.50% or less Ti, wherein the total content of Nb and Ti is 6(C+N) or more (C and N each represent contents of C and N), with the balance consisting of Fe and impurities. The weld metal part contains, by mass, 0.10-1.00% Al, and 15.00-24.00% Cr, wherein the total solid solution amount of C and N is 0.015 mass% or less.SELECTED DRAWING: None 【課題】耐食性及び耐熱性、特に、溶接金属部の耐食性及び耐熱性に優れるフェライト系ステンレス鋼溶接構造体を提供する。【解決手段】母材及び溶接金属部を含むフェライト系ステンレス鋼溶接構造体である。母材は、質量基準で、Ｃ：０．１００％以下、Ｍｎ：１．００％以下、Ｎｉ：１．００％以下、Ｐ：０．１００％以下、Ｓ：０．０５０％以下、Ｃｒ：１５．００～２４．００％、Ｎ：０．１００％以下、Ｃｕ：１．００％以下、Ｍｏ：１．００％以下、Ｓｉ：３．００％以下、Ａｌ：０．８０～５．００％、Ｎｂ：０．５０％以下、Ｔｉ：０．５０％以下を含み、Ｎｂ及びＴｉの合計含有量が６（Ｃ＋Ｎ）以上（Ｃ及びＮは、Ｃ及びＮの含有量をそれぞれ表す）であり、残部がＦｅ及び不純物からなる組成を有する。溶接金属部は、質量基準で、Ａｌ：０．１０～１．００％、Ｃｒ：１５．００～２４．００％を含み、Ｃ及びＮの合計固溶量が０．０１５質量％以下である。【選択図】なし