Abstract: A ferritic stainless steel and a heat exchanger using the ferritic stainless steel are provided. The ferritic stainless steel includes, in mass %, C: 0.030% or less, N: 0.020% or less, Si: 0.5% or less, Mn: 1.0% or less, P: 0.05% or less, S: 0.01% or less, Cr: 16% to 25%, Nb: 0.05% to 1.0%, Al: 0.003% to 0.20%, and a balance comprising Fe and unavoidable impurities. The Al oxide is present on the surface of the material, the surface coverage ratio by the Al oxide is 5% to 70%, the surface roughness in Ra measured by red laser is 0.010-0.15 ?m, and the thickness from the surface to the point, which includes the value of a half peak of the Al content on the surface, satisfies 300 nm or less, the value of a half peak of the Al content in an elemental profile expressed by a cation ratio.
Abstract: 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}<110>-orientation intensity at 4.0 or more and {311}<136>-orientation intensity at less than 3.0, a relationship rm??1.0t+3.0 (t(mm): sheet thickness, rm: average r-value) is satisfied, thereby providing a ferritic stainless steel sheet and a steel pipe with excellent formability.
Abstract: The present invention particularly has as its technical problem to provide austenitic stainless steel sheet used as the material for housings of turbochargers in which excellent heat resistance and workability are demanded. The austenitic stainless steel sheet according to the present invention comprises, by mass %, C: 0.005 to 0.2%, Si: 0.1 to 4%, Mn: 0.1 to 10%, Ni: 2 to 25%, Cr: 15 to 30%, N: 0.01 to less than 0.4%, Al: 0.001 to 1%, Cu: 0.05 to 4%, Mo: 0.02 to 3%, V: 0.02 to 1%, P: 0.05% or less, and S: 0.01% or less, comprises a balance of Fe and unavoidable impurities, and has an annealing twin frequency of 40% or more and is excellent in heat resistance.
Abstract: A steel material contains, in mass %, C: 0.005 to 0.050, N: 0.05 to 0.30, Si: 0.1 to 1.5, Mn: 0.1 to 7.0, P: 0.005 to 0.100, S: 0.0001 to 0.0200, Cr: 18.0 to 28.0, Cu: 0.1 to 3.0, Ni: 0.1 to 8.0, Mo: 0.1 to 5.0, Al: 0.001 to 0.050, B: 0.0001 to 0.0200, and Ca: 0.0001 to 0.0100. An area ratio of an austenitic phase ranges from 30% to 70% and formulae (I) and (II) below are satisfied. 1.03?[% Cr*F]/[% Cr]?1.40??Formula (I) 1.05?[% Mn*A]/[% Mn]?1.
Abstract: This ferritic stainless steel contains, by mass %, C: 0.001% to 0.030%; Si: 0.01% to 1.00%. Mn: 0.01% to 2.00%, P: 0.050% or less, S: 0.0100% or less, Cr: 11.0% to 30.0%, Mo: 0.01% to 3.00%, Ti: 0.001% to 0.050%, Al: 0.001% to 0.030%, Nb: 0.010% to 1.000%, and N: 0.050% or less, with a remainder being Fe and inevitable impurities, wherein an amount of Al, an amount of Ti, and an amount of Si (mass %) satisfy Al/Ti?8.4Si-0.78.
Abstract: The present invention provides a rolled ferritic stainless steel material excellent in corrosion resistance and toughness, in particular suitable as a material for a flange and a method for producing the same and flange part. The rolled ferritic stainless steel material contains, by mass %, C: 0.001 to 0.08%, Si: 0.01 to 1.0%, Mn: 0.01 to 1.0%, P: 0.01 to 0.05%, S: 0.0002 to 0.01%, Cr: 10.0 to 25.0%, and N: 0.001 to 0.05%, has a balance of Fe and unavoidable impurities, has a thickness of 5 mm or more, and has an area ratio of crystal grains with a <011> direction within 15° from the rolling direction of 20% or more in a cross-section parallel to the rolling direction at any location between the left and right ends of the steel sheet.
Abstract: A stainless steel exhibiting an excellent brazeability includes in mass %: C: from 0.001% to 0.1%; Si: from more than 1.5% to 4.0%; Mn: from 0.05% to 4.0%; Cr: from 10.5% to 30%; Ni: 35% or less; N: from 0.001% to 0.4%; one or both of Ti: 0.002% to 0.030% and Al: 0.002% to 0.10%; and a balance being Fe and inevitable impurities, in which an Si content, a Ti content and an Al content satisfy Formula 1, and an oxide film with a composition satisfying Formula 2 is formed on a surface of the stainless steel, Sim/(Tim+Alm)?40??Formula 1 1.2×SimFem?Sif/Fef?5×Sim/Fem??Formula 2 in Formula 1 and Formula 2, a suffix “f” expresses the oxide film in a unit of atom %, and a suffix “m” expresses a base material in a unit of mass %.
Abstract: The present invention provides a rolled ferritic stainless steel material excellent in corrosion resistance and toughness, in particular suitable as a material for a flange and a method for producing the same and flange part. The rolled ferritic stainless steel material contains, by mass %, C: 0.001 to 0.08%, Si: 0.01 to 1.0%, Mn: 0.01 to 1.0%, P: 0.01 to 0.05%, S: 0.0002 to 0.01%, Cr: 10.0 to 25.0%, and N: 0.001 to 0.05%, has a balance of Fe and unavoidable impurities, has a thickness of 5 mm or more, and has an area ratio of crystal grains with a <011> direction within 15° from the rolling direction of 20% or more in a cross-section parallel to the rolling direction at any location between the left and right ends of the steel sheet.
Abstract: The present invention particularly has as its technical problem to provide austenitic stainless steel sheet used as the material for housings of turbochargers in which excellent heat resistance and workability are demanded. The austenitic stainless steel sheet according to the present invention comprises, by mass %, C: 0.005 to 0.2%, Si: 0.1 to 4%, Mn: 0.1 to 10%, Ni: 2 to 25%, Cr: 15 to 30%, N: 0.01 to less than 0.4%, Al: 0.001 to 1%, Cu: 0.05 to 4%, Mo: 0.02 to 3%, V: 0.02 to 1%, P: 0.05% or less, and S: 0.01% or less, comprises a balance of Fe and unavoidable impurities, and has an annealing twin frequency of 40% or more and is excellent in heat resistance.
Abstract: A ferritic stainless steel for a fuel cell includes, in mass %, Cr: 11 to 25%, C: 0.03% or less, Si: 2% or less, Mn: 2% or less, Al: 0.5 to 4.0%, P: 0.05% or less, S: 0.01% or less, N: 0.03% or less, Ti: 1% or less, and a balance composed of Fe and unavoidable impurities. Furthermore, in the ferritic stainless steel, the maximal concentration of Al in a surface of the ferritic stainless steel is 30 mass % or more in cation ion fraction excepting O in an depth direction region having twice a thickness of an oxide film having less than 0.1 ?m.
Abstract: An automotive member or oil filler pipe includes: a member of ferritic stainless steel containing, in mass %, at most 0.015% of C, at most 0.015% of N, 10.5 to 18.0% of Cr, 0.01 to 0.80% of Si, 0.01 to 0.80% of Mn, at most 0.050% of P, at most 0.010% of S, 0.010 to 0.100% of Al, more than 0.3 to 1.5% of Mo, and one or both of 0.03 to 0.30% of Ti and Nb; and a metal fitting of an aluminized stainless steel sheet, which is attached to the member to define therebetween a gap structure to be exposed to a chloride environment, and has an Al-plating weight per unit area ranging from 20 to 150 g/m2 in the gap structure. Surfaces of the metal fitting and member not facing the gap are coated with a cation electrodeposition coating film having a thickness of 5 to 35 ?m.
Abstract: A Cr-containing ferritic stainless steel sheet is desired with improved corrosion resistance and rust resistance as well as improved ridging resistance. To achieve these results, the ferritic stainless steel sheet derives the relationship between Ap, which shows the ?-phase rate at 1100° C. due to a predetermined ingredient, and Sn in ferritic stainless steel which becomes a dual phase structure of ?+? in the hot rolling temperature region, applies and adds Sn, and hot rolls the steel to give a total rolling rate of 15% or more in 1100° C. or higher hot rolling to thereby obtain ferritic stainless steel sheet which has good ridging resistance, which also has excellent corrosion resistance and rust resistance, and which can be applied to general durable consumer goods, wherein 0.060?Sn?0.634?0.0082Ap and 10?Ap?70.
Abstract: A ferritic stainless steel sheet containing, by mass %, C: 0.020% or less, Cr: 10.0% to 25.0%, N: 0.020% or less, Sn: 0.010% to 0.50%, and one or more of Ti: 0.60% or less, Nb: 0.60% or less, V: 0.60% or less, and Zr: 0.60% or less so as to satisfy Equation (1): (Ti/48+V/51+Zr/91+Nb/93)/(C/12+N/14)?1.0, wherein a difference between a stress ?1 (N/mm2) after prestrain imparting tensile deformation with 7.5% of strain, and an upper yield stress ?2 (N/mm2) when the steel sheet is subjected to heat treatment at 200° C. for 30 minutes and then to tension again after the tensile deformation is 8 or less.
Abstract: This high-strength austenitic stainless steel having excellent hydrogen embrittlement resistance characteristics includes, by mass %, C: 0.2% or less, Si: 0.3% to 1.5%, Mn: 7.0% to 11.0%, P: 0.06% or less, S: 0.008% or less, Ni: 5.0% to 10.0%, Cr: 14.0% to 20.0%, Cu: 1.0% to 5.0%, N: 0.01% to 0.4%, and 0: 0.015% or less, with the balance being Fe and unavoidable impurities, wherein an average size of Cr-based carbonitrides is 100 nm or less, and an amount of the Cr-based carbonitrides is 0.001% to 0.5% in terms of % by mass.
Abstract: This high-strength austenitic stainless steel having excellent hydrogen embrittlement resistance characteristics includes, by mass %, C: 0.2% or less, Si: 0.3% to 1.5%, Mn: 7.0% to 11.0%, P: 0.06% or less, S: 0.008% or less, Ni: 5.0% to 10.0%, Cr: 14.0% to 20.0%, Cu: 1.0% to 5.0%, N: 0.01% to 0.4%, and 0: 0.015% or less, with the balance being Fe and unavoidable impurities, wherein an average size of Cr-based carbonitrides is 100 nm or less, and an amount of the Cr-based carbonitrides is 0.001% to 0.5% in terms of % by mass.
Abstract: This ferritic stainless steel sheet contains, in terms of % by mass, 0.02% or less of C, 0.02% or less of N, 0.10% to 0.60% of Si, 0.10% to 0.80% of Mn, 15.0% to 21.0% of Cr, more than 2.00% to 3.50% or less of Cu, 0.30% to 0.80% of Nb, 1.00% to 2.50% of Mo, and 0.0003% to 0.0030% of B, with a remainder being Fe and unavoidable impurities, wherein a maximum particle size of ?-Cu that is present in a structure is 20 nm to 200 nm.
Abstract: A steel material contains, in mass %, C: 0.005 to 0.050, N: 0.05 to 0.30, Si: 0.1 to 1.5, Mn: 0.1 to 7.0, P: 0.005 to 0.100, S: 0.0001 to 0.0200, Cr: 18.0 to 28.0, Cu: 0.1 to 3.0, Ni: 0.1 to 8.0, Mo: 0.1 to 5.0, Al: 0.001 to 0.050, B: 0.0001 to 0.0200, and Ca: 0.0001 to 0.0100. An area ratio of an austenitic phase ranges from 30% to 70% and formulae (I) and (II) below are satisfied. 1.03?[% Cr*F]/[% Cr]?1.40??Formula (I) 1.05?[% Mn*A]/[% Mn]?1.
Abstract: Ferritic stainless steel hot rolled sheet and steel strip excellent in toughness and corrosion resistance which have a predetermined chemical composition, have a Charpy impact value at 0° C. of 10 J/cm2 or more, and have a thickness of 5.0 to 9.0 mm.
Abstract: A Cr-containing ferritic stainless steel sheet is desired with improved corrosion resistance and rust resistance as well as improved ridging resistance. To achieve these results, the ferritic stainless steel sheet derives the relationship between Ap, which shows the ?-phase rate at 1100° C. due to a predetermined ingredient, and Sn in ferritic stainless steel which becomes a dual phase structure of ?+? in the hot rolling temperature region, applies and adds Sn, and hot rolls the steel to give a total rolling rate of 15% or more in 1100° C. or higher hot rolling to thereby obtain ferritic stainless steel sheet which has good ridging resistance, which also has excellent corrosion resistance and rust resistance, and which can be applied to general durable consumer goods, wherein 0.060?Sn?0.634?0.0082Ap and 10?Ap?70.
Abstract: This ferritic stainless steel contains, by mass %, C: 0.001% to 0.030%; Si: 0.01% to 1.00%. Mn: 0.01% to 2.00%, P: 0.050% or less, S: 0.0100% or less, Cr: 11.0% to 30.0%, Mo: 0.01% to 3.00%, Ti: 0.001% to 0.050%, Al: 0.001% to 0.030%, Nb: 0.010% to 1.000%, and N: 0.050% or less, with a remainder being Fe and inevitable impurities, wherein an amount of Al, an amount of Ti, and an amount of Si (mass %) satisfy Al/Ti?8.4Si-0.78.