STAINLESS STEEL MATERIAL AND DIFFUSION BONDED OBJECT

• Main Authors: IMAGAWA KAZUNARI, OKU MANABU, KUMANO NAOHITO
• Format: Patent
• Language: English; Japanese
• Published: 02.09.2021
• 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 stainless steel material having excellent diffusion bonding properties and high corrosion resistance of a bonded portion after diffusion bonding, and causing small thermal expansion by diffusion bonding.SOLUTION: The stainless steel material of the present invention includes a ferrite phase and a martensite phase, and contains C of 0.030 mass% or less, Si of 0.60 mass% or less, Mn of 2.0 mass% or less, P of 0.040 mass% or less, S of 0.003 mass% or less, Ni of 1.0 to 6.0 mass%, Cr of 17.5 to 22.0 mass%, Mo of 1.5 mass% or less, Cu of 2.0 mass% or less, Nb of 8(C+N) to 0.50 mass% (C and N represent their respective contents), Al of 0.10 mass% or less, and N of 0.030 mass% or less, with balance composed of Fe and unavoidable impurities, in which an average crystal grain size is 10 μm or less, and Ms=(3000×(0.068-(C+N))+50×(0.47-Si)+60×(1.33-Mn)+110×(8.9-Ni)+75×(14.6-Cr)-32)×5/9 shall be 180°C or higher.SELECTED DRAWING: None 【課題】拡散接合性に優れ、拡散接合後に溶接部の耐食性が高く且つ拡散接合による熱膨張が小さいステンレス鋼材を提供する。【解決手段】フェライト相及びマルテンサイト相を含み、Ｃ：０．０３０質量％以下、Ｓｉ：０．６０質量％以下、Ｍｎ：２．０質量％以下、Ｐ：０．０４０質量％以下、Ｓ：０．００３質量％以下、Ｎｉ：１．０〜６．０質量％、Ｃｒ：１７．５〜２２．０質量％、Ｍｏ：１．５質量％以下、Ｃｕ：２．０質量％以下、Ｎｂ：８（Ｃ＋Ｎ）〜０．５０質量％（Ｃ及びＮはそれぞれの含有量を表す）、Ａｌ：０．１０質量％以下、Ｎ：０．０３０質量％以下を含み、残部がＦｅ及び不可避的不純物からなる組成を有し、平均結晶粒径が１０μｍ以下、Ｍｓ＝（３０００×（０．０６８−（Ｃ＋Ｎ））＋５０×（０．４７−Ｓｉ）＋６０×（１．３３−Ｍｎ）＋１１０×（８．９−Ｎｉ）＋７５×（１４．６−Ｃｒ）−３２）×５／９を１８０℃以上とする。【選択図】なし