Abstract: A ferritic stainless steel sheet contains abut 0.01 percent by mass or less of carbon; about 1.0 percent by mass or less of silicon; about 1.5 percent by mass or less of manganese; about 11 to about 23 percent by mass of chromium; about 0.06 percent by mass or less of phosphorous; about 0.03 percent by mass or less of sulfur; about 1.0 percent by mass or less of aluminum; about 0.04 percent by mass or less of nitrogen; about 0.0005 to about 0.01 percent by mass of boron; about 0.3 percent by mass or less of vanadium; about 0.8 percent by mass or less of niobium and/or about 1.0 percent by mass or less of titanium wherein 18?Nb/(C+N)+2(Ti/(C+N))?60; and the balance being iron and unavoidable impurities. The average crystal grain diameter is about 40 ?m or less and the average surface roughness is about 0.3 ?m or less.

Abstract: The soft Cr-containing steel includes, on a % by mass basis, C: from about 0.001% to about 0.020%, Si: more than about 0.10% and less than about 0.50%, Mn: less than about 2.00%, P: less than about 0.060%, S: less than about 0.008%, Cr: from about 12.0% to about 16.0%, Ni: from about 0.05% to about 1.00%, N: less than about 0.020%, Nb: from about 10×(C+N) to about 1.00%, Mo: more than about 0.80% and less than about 3.00%, wherein the contents of alloying elements, represented by Si and Mo, respectively, on a % by mass, satisfy the formula Si≦1.2−0.4Mo, so as to prevent precipitation of the Laves phase and to stably secure an effect of increasing high-temperature strength due to solid solution Mo.

Abstract: A ferritic stainless steel sheet for fuel tanks and fuel pipes comprises, by mass percent, about 0.1% or less of C; about 1.0% or less of Si; about 1.5% or less of Mn; about 0.06% or less of P; about 0.03% or less of S; about 1.0% or less of Al; about 11% to about 20% Cr; about 2.0% or less of Ni; about 0.5% to about 3.0% Mo; about 0.02% to about 1.0% V; about 0.04% or less of N; at least one of about 0.01% to about 0.8% Nb and about 0.01% to about 1.0% Ti; and the balance being Fe and incidental impurities. The ferritic stainless steel sheet is produced by rough-rolling a slab having the above composition; hot-rolling the rough-rolled sheet under a linear pressure of at least about 3.5 MN/m at a final pass in the finish rolling; cold-rolling the hot-rolled sheet at a gross reduction rate of at least about 75%; and annealing the cold-rolled sheet. The cold-rolling step includes one rolling stage or at least two rolling stages including intermediate annealing.

Abstract: A ferritic stainless steel sheet for use in automobile fuel tanks and fuel pipes having smooth surface and resistance to organic acid is provided. The sheet contains, by mass, not more than about 0.1% C, not more than about 1.0 Si, not more than about 1.5% Mn, not more than about 0.06% P, not more than about 0.03% S, about 11% to about 23% Cr, not more than about 2.0% Ni, about 0.5% to about 3.0% Mo, not more than about 1.0% Al, not more than about 0.04% N, at least one of not more than about 0.8% Nb and not more than about 1.0% Ti, and the balance being Fe and unavoidable impurities, satisfying the relationship: 18≦Nb/(C+N)+2Ti/(C+N)≦60, wherein C, N, Nb, and Ti in the relationship represent the C, N, Nb, and Ti contents by mass percent, respectively. A process for making the same is also provided.

Abstract: The invention provides a Fe—Cr alloy structure containing Cr of about 6% or more by mass but about 25% or less by mass, having a corrosion-resistant paint film containing metal powder having ionization tendencies greater than iron, with a content of the metal powder of about 20% or more by volume but about 60% or less by volume in a dry paint film, with a dry film thickness of about 5 &mgr;m or more but about 100 &mgr;m or less; and a manufacturing method thereof; whereby excellent corrosion resistance and excellent adhesion is provided.

Abstract: The soft Cr-containing steel includes, on a % by mass basis, C: from about 0.001% to about 0.020%, Si: more than about 0.10% and less than about 0.50%, Mn: less than about 2.00%, P: less than about 0.060%, S: less than about 0.008%, Cr: from about 12.0% to about 16.0%, Ni: from about 0.05% to about 1.00%, N: less than about 0.020%, Nb: from about 10×(C+N) to about 1.00%, Mo: more than about 0.80% and less than about 3.00%, wherein the contents of alloying elements, represented by Si and Mo, respectively, on a % by mass, satisfy the formula Si ≦1.2−0.4 Mo, so as to prevent precipitation of the Laves phase and to stably secure an effect of increasing high-temperature strength due to solid solution Mo.

Abstract: A ferritic stainless steel sheet for fuel tanks and fuel pipes comprises, by mass percent, about 0.1% or less of C; about 1.0% or less of Si; about 1.5% or less of Mn; about 0.06% or less of P; about 0.03% or less of S; about 1.0% or less of Al; about 11% to about 20% Cr; about 2.0% or less of Ni; about 0.5% to about 3.0% Mo; about 0.02% to about 1.0% V; about 0.04% or less of N; at least one of about 0.01% to about 0.8% Nb and about 0.01% to about 1.0% Ti; and the balance being Fe and incidental impurities. The ferritic stainless steel sheet is produced by rough-rolling a slab having the above composition; hot-rolling the rough-rolled sheet under a linear pressure of at least about 3.5 MN/m at a final pass in the finish rolling; cold-rolling the hot-rolled sheet at a gross reduction rate of at least about 75%; and annealing the cold-rolled sheet. The cold-rolling step includes one rolling stage or at least two rolling stages including intermediate annealing.

Abstract: A ferritic stainless steel sheet for use in automobile fuel tanks and fuel pipes having smooth surface and resistance to organic acid is provided. The sheet contains, by mass, not more than about 0.1% C, not more than about 1.0 Si, not more than about 1.5 % Mn, not more than about 0.06% P, not more than about 0.03% S, about 11% to about 23% Cr, not more than about 2.0% Ni, about 0.5% to about 3.0% Mo, not more than about 1.0% Al, not more than about 0.04% N, at least one of not more than about 0.8% Nb and not more than about 1.0% Ti, and the balance being Fe and unavoidable impurities, satisfying the relationship: 18≦Nb/(C+N)+2Ti/(C+N)≦60, wherein C, N, Nb, and. Ti in the relationship represent the C, N, Nb, and Ti contents by mass percent, respectively. A process for making the same is also provided.

Abstract: A ferritic stainless steel sheet contains abut 0.01 percent by mass or less of carbon; about 1.0 percent by mass or less of silicon; about 1.5 percent by mass or less of manganese; about 11 to about 23 percent by mass of chromium; about 0.06 percent by mass or less of phosphorous; about 0.03 percent by mass or less of sulfur; about 1.0 percent by mass or less of aluminum; about 0.04 percent by mass or less of nitrogen; about 0.0005 to about 0.01 percent by mass of boron; about 0.3 percent by mass or less of vanadium; about 0.8 percent by mass or less of niobium and/or about 1.0 percent by mass or less of titanium wherein 18≦Nb/(C+N)+2(Ti/(C+N))≦60; and the balance being iron and unavoidable impurities. The average crystal grain diameter is about 40 &mgr;m or less and the average surface roughness is about 0.3 &mgr;m or less.

Abstract: A ferritic stainless steel sheet for use in automobile fuel tanks and fuel pipes having smooth surface and resistance to organic acid is provided. The sheet contains, by mass, not more than about 0.1% C, not more than about 1.0 Si, not more than about 1.5% Mn, not more than about 0.06% P, not more than about 0.03% S, about 11% to about 23% Cr, not more than about 2.0% Ni, about 0.5% to about 3.0% Mo, not more than about 1.0% Al, not more than about 0.04% N, at least one of not more than about 0.8% Nb and not more than about 1.0% Ti, and the balance being Fe and unavoidable impurities, satisfying the relationship: 18≦Nb/(C+N)+2Ti/(C+N)≦60, wherein C, N, Nb, and Ti in the relationship represent the C, N, Nb, and Ti contents by mass percent, respectively. A process for making the same is also provided.

Abstract: A ferritic stainless steel sheet contains abut 0.01 percent by mass or less of carbon; about 1.0 percent by mass or less of silicon; about 1.5 percent by mass or less of manganese; about 11 to about 23 percent by mass of chromium; about 0.06 percent by mass or less of phosphorous; about 0.03 percent by mass or less of sulfur; about 1.0 percent by mass or less of aluminum; about 0.04 percent by mass or less of nitrogen; about 0.0005 to about 0.01 percent by mass of boron; about 0.3 percent by mass or less of vanadium; about 0.8 percent by mass or less of niobium and/or about 1.0 percent by mass or less of titanium wherein 18≦Nb/(C+N)+2(Ti/(C+N))≦60; and the balance being iron and unavoidable impurities. The average crystal grain diameter is about 40 &mgr;m or less and the average surface roughness is about 0.3 &mgr;m or less.

Abstract: A ferritic stainless steel sheet for use in automobile fuel tanks and fuel pipes having smooth surface and resistance to organic acid is provided. The sheet contains, by mass, not more than about 0.1% C, not more than about 1.0 Si, not more than about 1.5% Mn, not more than about 0.06% P, not more than about 0.03% S, about 11% to about 23% Cr, not more than about 2.0% Ni, about 0.5% to about 3.0% Mo, not more than about 1.0% Al, not more than about 0.04% N, at least one of not more than about 0.8% Nb and not more than about 1.0% Ti, and the balance being Fe and unavoidable impurities, satisfying the relationship: 18≦Nb/(C+N)+2Ti/(C+N)≦60, wherein C, N, Nb, and Ti in the relationship represent the C, N, Nb, and Ti contents by mass percent, respectively. A process for making the same is also provided.

Abstract: A ferritic stainless steel sheet for fuel tanks and fuel pipes comprises, by mass percent, about 0.1% or less of C; about 1.0% or less of Si; about 1.5% or less of Mn; about 0.06% or less of P; about 0.03% or less of S; about 1.0% or less of Al; about 11% to about 20% Cr; about 2.0% or less of Ni; about 0.5% to about 3.0% Mo; about 0.02% to about 1.0% V; about 0.04% or less of N; at least one of about 0.01% to about 0.8% Nb and about 0.01% to about 1.0% Ti; and the balance being Fe and incidental impurities. The ferritic stainless steel sheet is produced by rough-rolling a slab having the above composition; hot-rolling the rough-rolled sheet under a linear pressure of at least about 3.5 MN/m at a final pass in the finish rolling; cold-rolling the hot-rolled sheet at a gross reduction rate of at least about 75%; and annealing the cold-rolled sheet. The cold-rolling step includes one rolling stage or at least two rolling stages including intermediate annealing.

Abstract: The soft Cr-containing steel includes, on a % by mass basis, C: from about 0.001% to about 0.020%, Si: more than about 0.10% and less than about 0.50%, Mn: less than about 2.00%, P: less than about 0.060%, S: less than about 0.008%, Cr: from about 12.0% to about 16.0%, Ni: from about 0.05% to about 1.00%, N: less than about 0.020%, Nb: from about 10×(C+N) to about 1.00%, Mo: more than about 0.80% and less than about 3.00%, wherein the contents of alloying elements, represented by Si and Mo, respectively, on a % by mass, satisfy the formula Si ≦1.2-0.4 Mo, so as to prevent precipitation of the Laves phase and to stably secure an effect of increasing high-temperature strength due to solid solution Mo.

Abstract: Fe—Cr alloy having excellent weldability and initial rust resistance with no requirement of greatly increasing the amount of elements such as Ni, Cu, Cr or Mo, addition of Nb or Ti and, further, excess reduction of C and N, in which the Fe—Cr alloy containing Cr in an amount of more than about 8.0 mass % and less than about 15 mass % is controlled specifically for the ingredients to contain Co: from about 0.01 mass % to about 0.5 mass %, V: from about 0.01 mass % to about 0.5 mass % and W: from about 0.001 mass % to about 0.05 mass %, and a value X represented by the following equation (1) and, preferably, a value Z represented by the following equation (2) satisfy: X≦11.0, and 0.03≦Z≦1.5 respectively: X value=Cr(mass %)+Mo(mass %)+1.5Si(mass %)+0.5Nb(mass %)+0.2V(mass %)+0.3W(mass %)+8Al(mass %)−Ni(mass %)−0.6Co(mass %)−0.5Mn(mass %)−30C(mass %)−30N(mass %)−0.

Abstract: Fe—Cr alloy having excellent weldability and initial rust resistance with no requirement of greatly increasing the amount of elements such as Ni, Cu, Cr or Mo, addition of Nb or Ti and, further, excess reduction of C and N, in which the Fe—Cr alloy containing Cr in an amount of more than about 8.

Abstract: A ferritic stainless steel sheet having less planar anisotropy and excellent anti-ridging characteristics is disclosed. The sheet includes not more than about 0.02 wt % of C, about 0.01-1.0 wt % of Si, about 0.01-1.0 wt % of Mn, not more than about 0.08 wt % of P, not more than about 0.01 wt % of S, about 0.005-0.30 wt % of Al, about 11-50 wt % of Cr, about 0.1-5.0 wt % of Mo, not more than about 0.03 wt % N, with the contents of C and N satisfying the relations: about 0.005 wt %.ltoreq.(C+N)<about 0.03 wt %, and (C/N)<about 0.6. The sheet also includes Ti in an amount to satisfy the relation: about 5.ltoreq.Ti/(C+N).ltoreq.about 30. The balance of the sheet includes Fe and incidental impurities, with the sheet having an X-ray integral intensity ratio (222)/(310) of not less than about 35 in a plane parallel to a sheet surface at a depth of 1/4 of the sheet thickness from the sheet surface.

Abstract: A ferritic stainless steel exhibiting excellent atmospheric corrosion resistance and crevice corrosion resistance can be provided by positively adding P thereto and by adequately adjusting Ca and Al. The ferritic stainless steel according to the present invention essentially consists of, in weight percentages,C: about 0.05% or lessSi: about 1.0% or lessCr: about 11% or more and less than about 20%Mn: about 1.0% or lessN: about 0.10% or lessS: about 0.03% or lessCa: about 5 ppm or more and about 50 ppm or lessAl: about 0.5% or lessP: more than about 0.04% and about 0.20% or lessand the balance being iron and incidental impurities. The stainless steel according to the present invention may also contain at least one element selected from a group (1) consisting of about 6% or less of Mo, group (2) consisting of about 1.0% or less of Cu, about 3% or less of Ni and about 3% or less of Co, or group (3) consisting of about 1.0% or less of Ti, about 1.0% or less of Nb, about 1.0% or less of V, about 1.

Abstract: High Cr content, P added ferritic stainless steel containing, in % by weight, C: up to 0.02%, Si: up to 1.0%, Mn: up to 1.0%, S: up to 0.03%, Cr: from more than 20% to 40%, N: up to 0.015%, Al: up to 0.5%, and P: from more than 0.06% to 0.20%, the balance being Fe and incidental impurities, is improved in atmospheric corrosion resistance and rust prevention. The stainless steel may further contain at least one element selected from the following groups: (1) Mo: up to 4.0%; (2) one or more elements of Ti: up to 1.0%, Nb: up to 1.0%, Ta: up to 1.0%, V: up to 1.0%, W: up to 1.0%, Zr: up to 1.0%, and B: up to 0.01%; and (3) one or more elements of Cu: up to 1.0%, Ni: up to 5.0%, and Co: up to 1.0%.

Abstract: A sheet metal made from a ferritic stainless steel alloy which has an improved corrosion resistivity and is suitable for use in manufacturing exterior building material, in particular, roofing material, by means of forming process such as roll-forming, without formation of pocket wave. The steel alloy comprises 10-32 wt % of Cr and 0.005-0.1 wt %, in total, of C and N, the balance being Fe and unavoidable impurities. The sheet metal has been processed to present a mechanical property that, when tested in a tensile test conducted for a test piece sampled in the widthwise direction of cold-rolling and measured at the elastic limit reached in the test, a strain ratio is equal to or greater than 2.5.The method of making the sheet metal comprises the steps of: cold rolling a steel slab into a sheet metal, subjecting the thus obtained sheet metal to final annealing, subjecting the sheet metal to skin-pass rolling, and, subjecting the resulting sheet metal to aging process at a temperature of 200.degree.-550.degree.