Nippon Steel Stainless Steel Corporation

Kou Nishimura

Yoshiharu Inoue

Junichi Hamada

Jun Araki

Toshio Tanoue

Nozomu Fukuda

A ferritic stainless steel sheet is provided that has a predetermined chemical composition, wherein: a grain size number is 6.0 or more; the ferritic stainless steel sheet satisfies the formulas [A+B≥9.0] and [X+Y≥9.0] with respect to crystal orientation intensities of a ferrite phase obtained by X-ray diffraction; and the sheet thickness is 1.0 mm or more. A represents a {111}<112> crystal orientation intensity at a center portion of sheet thickness, B represents a {111}<112> crystal orientation intensity at a ⅛ portion of the sheet thickness, X represents a {322}<236> crystal orientation intensity at a center portion of sheet thickness, and Y represents a {322}<236> crystal orientation intensity at a ⅛ portion of the sheet thickness.

Ferritic stainless steel sheet, production method thereof, and ferritic stainless member

A ferritic stainless steel sheet includes a base metal and a nitrided layer that is formed on a surface of the base metal, a chemical composition of the base metal contains, in mass %, C: 0.001 to 0.020%, Si: 0.01 to 1.50%, Mn: 0.01 to 1.50%, P: 0.010 to 0.050%, S: 0.0001 to 0.010%, Cr: 16.0 to 25.0%, N: 0.001 to 0.030%, Ti: 0.01 to 0.30%, and optional elements, with the balance: Fe and unavoidable impurities, a steel microstructure of the base metal includes, in volume ratio, 95% or more of a ferritic phase, the nitrided layer is a layer that is present in a region from a surface of a rolled surface to a 0.05 μm depth position in a sheet thickness direction, and an average nitrogen concentration in the nitrided layer is, in mass %, 0.80% or more.

Ferritic stainless steel sheet

A ferritic stainless steel sheet and a steel pipe as a material suitable for a heat-resistant component that is required to have especially excellent formability are provided. The ferritic stainless steel sheet contains 10 to 20 mass % of Cr and a predetermined amount of C, Si, Mn, P, S, Al and one or both of Ti and Nb, a {111}-orientation intensity being 5 or more and {411}-orientation intensity being less than 3 at a portion in the vicinity of a sheet-thickness central portion of the ferritic stainless steel sheet. Further, with similar composition and by setting {111}&#x3c;110&#x3e;-orientation intensity at 4.0 or more and {311}&#x3c;136&#x3e;-orientation intensity at less than 3.0, a relationship r&#x2265;&#x2212;1.0t+3.0 (t(mm): sheet thickness, r: average r-value) is satisfied, thereby providing a ferritic stainless steel sheet and a steel pipe with excellent formability.

Growing community of inventors

Tokyo, Japan

Kou Nishimura