Abstract: A ferritic stainless steel that a composition including in terms of % by mass, C: 0.015% or less, Si: 1.0% or less, Mn: 1.0% or less, P: 0.040% or less, S: 0.010% or less, Cr: 10.0% to 23.0%, Al: 0.2% to 1.0%, N: 0.015% or less, Cu: 1.0% to 2.0%, Nb: 0.30% to 0.65%, Ti: 0.50% or less, O: 0.0030% or less, and the balance being Fe and unavoidable impurities, wherein a Si content and an Al content satisfy Si?Al, and the Al content and an O content satisfy Al/O?100.

Abstract: A steel slab having a composition containing C: more than 0.07% and 0.2% or less, Si: 2.0% or less, Mn: 1.0% to 3.0%, Al: 0.1% or less, Ti: 0.05% to 0.3%, and V: 0.05% to 0.3% on a mass percent basis is heated to 1100° C. or more and is subjected to rough rolling and finish rolling. In the finish rolling, the total rolling reduction of two final passes is 30% or more, and the finish rolling temperature ranges from (Ar3 transformation temperature) to (Ar3 transformation temperature+120° C.). Cooling is started within 2 seconds after the finish rolling. Coiling is performed at an average cooling rate of 40° C./s or more at a coiling temperature in the range of 300° C. to 500° C. The resulting high-strength hot-rolled steel sheet has a microstructure in which a bainite phase constitutes more than 90% by volume, the average lath interval of bainite is 0.

Abstract: The ferritic stainless steel sheet contains, in mass%, C: 0.020% or less, Si: 0.6% or less, Mn: 0.5% or less, P: 0.04% or less, S: 0.010% or less, Al: 0.015% or more and 0.20% or less, Cr: 17.0% or more and 24.0% or less, Ni: less than 0.6%, N: 0.020% or less, Ca: 0.0002% or more and 0.0020% or less, and O: 0.0050% or less and further contains one or two selected from Ti: 0.01% or more and 0.45% or less and Nb: 0.01% or more and 0.55% or less, with the balance being Fe and unavoidable impurities. The ferritic stainless steel sheet satisfies (Ti+Nb×48/93)/(C+N)?8.0 (where Ti, Nb, C, and N represent the contents (% by mass) of these elements, respectively).

Abstract: A martensitic stainless steel has a chemical composition containing, by mass %, C: 0.030% or more and less than 0.20%, Si: 0.01% or more and 2.0% or less, Mn: 0.01% or more and 3.0% or less, P: 0.050% or less , S: 0.010% or less, Cr: 10.0% or more and 16.0% or less, Ni: 0.01% or more and 0.80% or less, Al: 0.001% or more and 0.50% or less, Zr: 0.005% or more and 0.50% or less, and N: 0.030% or more and less than 0.20%, with the balance consisting of Fe and inevitable impurities.

Abstract: A ferritic stainless steel sheet is provided. The ferritic stainless steel includes, in mass %, C: 0.020% or less, Si: 0.05 to 0.50%, Mn: 0.05 to 0.50%, P: 0.040% or less, S: 0.030% or less, Al: 0.001 to 0.150%, Cr: 18.0 to 25.0%, Ti: 0.01 to 0.50%, Ca: 0.0001 to 0.0015%, O (oxygen): 0.0015 to 0.0040%, and N: 0.025% or less, with the balance being Fe and incidental impurities. The ferritic stainless steel sheet further satisfies formula (1), below: 0.5?PBI?20.0 . . . (1) (where PBI=(7Al+2Ti+Si+10Zr+130Ca)×O (oxygen)×1000, and Al, Ti, Si, Zr, Ca, and O (oxygen) in the formula each represent a content [mass %] of a corresponding element in the ferritic stainless steel sheet, and the content of an element not included in the ferritic stainless steel sheet is 0).

Abstract: Provided is a ferritic stainless steel sheet excellent in terms of corrosion resistance with which a decrease in the quantity of surface defects and an improvement in toughness are realized at the same time. The ferritic stainless steel sheet has a chemical composition containing, by mass %, C: 0.020% or less, Si: 0.05% to 0.40%, Mn: 0.05% to 1.00%, P: 0.040% or less, S: 0.030% or less, Al: 0.001% to 0.15%, Cr: 20.0% to 23.0%, Ni: 0.01% to 0.80%, Cu: 0.30% to 0.80%, Ti: 0.10% to 0.50%, Nb: 0.010% to 0.150%, Zr: 0.005% to 0.150%, N: 0.020% or less, and the balance being Fe and inevitable impurities, in which relational expression (1) below is satisfied. Zr?Nb?Ti??(1) (Here, each of Zr, Nb, and Ti in relational expression (1) denotes the content (mass %) of the corresponding chemical element.

Abstract: The present invention provides stainless steel sheets including a Ni and O-containing coating on the surface and having excellent weld penetration characteristics and excellent crevice corrosion resistance, and provides a method for producing such stainless steel sheets. A stainless steel sheet includes a Ni and O-containing coating on a surface of the stainless steel sheet. The Ni and O-containing coating has a coating weight of greater than or equal to 0.1 g/m2 and less than or equal to 20 g/m2. The Ni and O-containing coating has a composition including, in at. %, Ni: greater than or equal to 25% and less than or equal to 60%, and O: greater than or equal to 40% and less than or equal to 70%.

Abstract: A stainless steel sheet for fuel cell separators including a substrate made of stainless steel sheet, and low-electrical-resistivity metal particles, where the substrate has a textured structure formed on a surface thereof with the average interval between the projected parts of the textured structure being 10 nm or more and 300 nm or less, the low-electrical-resistivity metal particles have an average particle size of 50 nm to 1.0 ?m, the low-electrical-resistivity metal particles are attached to the surface of the substrate having the textured structure at a density of 1.0 particle or more for 1 ?m2, and a ratio of the average particle size of the low-electrical-resistivity metal particles to the average interval between the projected parts is 1.0 to 15.0.

Abstract: Provided are a material for cold rolled stainless steel sheets having sufficient corrosion resistance, excellent surface quality, excellent formability, and excellent ridging resistance; a method for manufacturing the same; and a cold rolled steel sheet. A material for cold rolled stainless steel sheets according to the present invention contains C: 0.005% to 0.025%, Si: 0.02% to 0.50%, Mn: 0.55% to 1.0%, P: 0.040% or less, S: 0.01% or less, Cr: 15.5% to 18.0%, Ni: 0.01% to 1.0%, Al: 0.001% to 0.10%, and N: 0.005% to 0.025% on a mass basis, the remainder being Fe and inevitable impurities, and has a metallographic structure containing 5% to 20% of a martensite phase in terms of volume fraction, the remainder being a ferrite phase.

Abstract: A lubricant coating material for stainless steel sheets that has excellent press formability (deep drawability and mold galling resistance) and a lubricated stainless steel sheet in which the same is used includes: a lubricant coating material for stainless steel sheets that contains an acrylic resin and polyethylene wax, the polyethylene wax having a melting point of 115° C. or greater, and the content of the polyethylene wax ranging from greater than 20 parts by mass to 50 parts by mass with respect to 100 parts by mass of the acrylic resin; and a lubricated stainless steel sheet in which the same is used.

Abstract: A method for manufacturing a hot rolled steel sheet having a low yield ratio and that is excellent in low-temperature toughness, the steel sheet having a specified chemical composition. The method comprises hot rolling a steel material into a steel sheet, cooling the steel material using a cooling process comprising a first cooling and a second cooling, and performing a coiling process on the steel sheet in such a manner that the coiling temperature is 450° C. or more in terms of surface temperature of the steel sheet.

Abstract: Provided is a ferritic stainless steel excellent in oxidation resistance and thermal fatigue resistance. The ferritic stainless steel contains, in mass %, C: 0.020% or less, Si: more than 0.1% and 3.0% or less, Mn: 0.05 to 2.0%, P: 0.050% or less, S: 0.010% or less, Al: 0.3 to 6.0%, N: 0.020% or less, Cr: 12 to 30%, Nb: more than 0.3% and 1.0% or less, Ti: 0.01 to 0.5%, Mo: 0.3 to 6.0%, Co: 0.01 to 3.0%, and Ni: 0.02 to 1.0%, the balance being Fe and unavoidable impurities. Moreover, Si+Al>1.0%, Al—Mn>0%, and Nb—Ti>0% hold.

Abstract: A high strength hot rolled steel sheet is provided with low yield ratio and that is excellent in low-temperature toughness. The hot rolled steel sheet can be used as a raw material of a steel pipe. The steel sheet has a chemical composition containing C: 0.03% or more and 0.10% or less, Si: 0.01% or more and 0.50% or less, Mn: 1.4% or more and 2.2% or less, P: 0.025% or less, S: 0.005% or less, Al: 0.005% or more and 0.10% or less, Nb: 0.02% or more and 0.10% or less, Ti: 0.001% or more and 0.030% or less, Mo: 0.01% or more and 0.50% or less, Cr: 0.01% or more and 0.50% or less, and Ni: 0.01% or more and 0.50% or less, in which the condition that Moeq is 1.4% or more and 2.2% or less.

Abstract: Provided are a hot rolled ferritic stainless steel sheet and a hot rolled and annealed ferritic stainless steel sheet and methods for manufacturing these steel sheets. A hot rolled ferritic stainless steel sheet having a chemical composition containing, by mass %, C: 0.005% to 0.060%, Si: 0.02% to 0.50%, Mn: 0.01% to 1.00%, P: 0.04% or less, S: 0.01% or less, Cr: 15.5% to 18.0%, Al: 0.001% to 0.10%, N: 0.005% to 0.100%, Ni: 0.1% to 1.0%, and the balance being Fe and inevitable impurities and an absolute value of planar anisotropy in terms of modulus of longitudinal elasticity below of 35 GPa or less.

Abstract: Provided is a ferritic stainless steel sheet for a urea SCR casing which is excellent in terms of corrosion resistance in a urea SCR environment and which increases the durability of a urea SCR casing. The steel sheet has a chemical composition containing, by mass %, C: 0.020% or less, Si: 0.01% or more and 0.50% or less, Mn: 0.01% or more and 0.50% or less, P: 0.040% or less, S: 0.010% or less, Al: 0.01% or more and 0.20% or less, Cr: 20.5% or more and 24.0% or less, Cu: 0.40% or more and 0.80% or less, Ni: 0.05% or more and 0.6% or less, N: 0.020% or less, one or both selected from among Ti: 0.01% or more and 0.40% or less and Nb: 0.01% or more and 0.55% or less, and the balance being Fe and inevitable impurities, in which the relationship Ti+Nb×48/93?8×(C+N) (in the relational expression, Ti, Nb, C, and N denote the contents (mass %) of the corresponding chemical elements) is satisfied.

Abstract: Provided are a ferritic stainless steel sheet and a method for manufacturing the steel sheet. The ferritic stainless steel sheet according to the present invention has a chemical composition containing, by mass %, C: 0.005% to 0.025%, Si: 0.02% to 0.50%, Mn: 0.55% to 1.00%, P: 0.04% or less, S: 0.01% or less, Al: 0.001% to 0.10%, Cr: 15.5% to 18.0%, Ni: 0.1% to 1.0%, N: 0.005% to 0.025%, and the balance being Fe and inevitable impurities, an elongation after fracture of 28% or more, an average r-value of 0.75 or more, and a minimum value of maximum logarithmic strain at the forming limit, which is, determined on the basis of a forming limit diagram (FLD), of 0.15 or more.

Abstract: A metal sheet for separators of polymer electrolyte fuel cells comprises: a substrate made of metal; and a surface-coating layer with which a surface of the substrate is coated, with a strike layer in between, wherein a coating ratio of the strike layer on the substrate is 2% to 70%, the strike layer is distributed in a form of islands, and a maximum diameter of the islands of the strike layer as coating portions is 1.00 ?m or less and is not greater than a thickness of the surface-coating layer.

Abstract: The disclosure is to provide a martensitic stainless steel excellent in strength, workability and corrosion resistance. The martensitic stainless steel comprises a chemical composition containing, in mass %: C: 0.020% or more and less than 0.10%, Si: 0.01% or more and 2.0% or less, Mn: 0.01% or more and 3.0% or less, P: 0.050% or less, S: 0.050% or less, Cr: 10.0% or more and 16.0% or less, Ni: 0.01% or more and 0.80% or less, Al: 0.001% or more and 0.50% or less, and N: more than 0.050% and 0.20% or less, satisfying N %?C %, and the balance containing Fe and incidental impurities, where C % and N % indicate respectively the contents of C and N (mass %) in the steel.

Abstract: A metal sheet for separators of polymer electrolyte fuel cells having both excellent corrosion resistance in the use environment of separators of polymer electrolyte fuel cells and excellent adhesion property between a substrate and a surface-coating layer even in the case where the surface-coating layer is made thinner is provided. A metal sheet for separators of polymer electrolyte fuel cells includes: a substrate made of metal; and a surface-coating layer with which the substrate is coated, with a strike layer in between, wherein a coating weight of the strike layer is 0.001 g/m2 to 1.0 g/m2.

Abstract: Provided is a ferritic stainless steel having a chemical composition containing, in mass %: 0.003% to 0.025% of C; 0.05% to 1.00% of Si; 0.05% to 1.00% of Mn; 0.04% or less of P; 0.01% or less of S; 16.0% to 23.0% of Cr; 0.20% to 0.80% of Cu; 0.05% to 0.60% of Ni; 0.20% to 0.70% of Nb; 0.005% to 0.020% of N; and the balance being Fe and incidental impurities, in which a nitrogen-enriched layer is present that has a nitrogen concentration peak value of 0.03 mass % to 0.30 mass % at a depth of within 0.05 ?m of a surface of the steel.