A martensitic stainless steel containing, by mass %, C: 0.20% to 0.40%, N: 0.1% or less, Mo: 3% or less, and Cr: 12.0% to 16.0%, such that 0.3%C+N0.4% and a PI value (=Cr+3.3 Mo+16 N) is 18 or more, with the remainder being substantially Fe and unavoidable impurities is quenched from a temperature of 1,030 C. to 1,140 C. and subjected to a subzero treatment and tempering so as to obtain a prior austenite crystal grain size of a surface layer of 30 m to 100 m and a surface hardness of 58 HRc to 62 HRc.

A martensitic stainless steel containing, by mass %, C: 0.20% to 0.40%, N: 0.1% or less, Mo: 3% or less, and Cr: 12.0% to 16.0%, such that 0.3%C+N0.4% and a PI value (=Cr+3.3 Mo+16 N) is 18 or more, with the remainder being substantially Fe and unavoidable impurities is quenched from a temperature of 1,030 C. to 1,140 C. and subjected to a subzero treatment and tempering so as to obtain a prior austenite crystal grain size of a surface layer of 30 m to 100 m and a surface hardness of 58 HRc to 62 HRc.

There is provided an austenitic stainless steel material having a consistent high-strength across the overall length of the steel material, which has a chemical composition consisting of, in mass percent: C: 0.10% or less, Si: 1.0% or less, Mn: 3 to 8%, P: 0.05% or less, S: 0.03% or less, Ni: 10 to 20%, Cr: 15 to 30%, N: 0.20 to 0.70%, with the balance being Fe and impurities, the austenitic stainless steel material having a grain size number of 6.0 or greater, the grain size number conforming to ASTM E 112 tensile strength of the austenitic stainless steel material is 800 MPa or more, and the difference between the maximum value and the minimum value of the tensile strength is 50 MPa or smaller. The number of alloy carbo-nitrides having a circle equivalent diameter of larger than 1000 nm in the steel is 10/mm.sup.2 or more.

An article, for example a turbomachinery article is presented. The article includes a weldable first component having a base portion and a flange portion. The flange portion is outwardly projecting normal to a surface of the base portion; and is joined with the base portion by a solid state joint. The base portion comprises a nanostructured ferritic alloy; and the flange portion comprises a steel substantially free of oxide nanofeatures. The first component is joined to a second component through the flange portion of the first component by a weld joint.

An article, for example a turbomachinery article is presented. The article includes a weldable first component having a base portion and a flange portion. The flange portion is outwardly projecting normal to a surface of the base portion; and is joined with the base portion by a solid state joint. The base portion comprises a nanostructured ferritic alloy; and the flange portion comprises a steel substantially free of oxide nanofeatures. The first component is joined to a second component through the flange portion of the first component by a weld joint.

The invention concerns a component made of a steel alloy comprising iron and as alloying element copper, in particular consisting of (in wt % in relation to the total alloy, wherein the sum of all constituents equals 100 wt %) iron96, carbon 0.04 to 0.12, copper 0.5 to 2.0, manganese+silicon+chromium+nickel 0.5 to 2.5, titanium 0 to 0.1, boron 0 to 0.005, and typical unavoidable impurities. In the production of semi-finished goods and of components, a combination of cold working and annealing treatment below the recrystallization temperature is used in order to thus obtain advantageous properties with regard to strength and ductility.

The invention concerns a component made of a steel alloy comprising iron and as alloying element copper, in particular consisting of (in wt % in relation to the total alloy, wherein the sum of all constituents equals 100 wt %) iron96, carbon 0.04 to 0.12, copper 0.5 to 2.0, manganese+silicon+chromium+nickel 0.5 to 2.5, titanium 0 to 0.1, boron 0 to 0.005, and typical unavoidable impurities. In the production of semi-finished goods and of components, a combination of cold working and annealing treatment below the recrystallization temperature is used in order to thus obtain advantageous properties with regard to strength and ductility.

A high-ductility, high-strength electrolytic zinc-based coated steel sheet includes an electrolytic zinc-based coating on a base steel sheet, in which the base steel sheet has a predetermined composition and a steel microstructure in which the total area percentage of one or two of martensite containing a carbide having an average particle size of 50 nm or less and bainite containing a carbide having an average particle size of 50 nm or less is 90% or more in the entire steel microstructure, the total area percentage of one or two of the martensite containing a carbide having an average particle size of 50 nm or less and the bainite containing a carbide having an average particle size of 50 nm or less is 80% or more in a region extending from the surface of the base steel sheet to a depth of ? of the thickness of the base steel sheet.

A high-yield-ratio high-strength electrogalvanized steel sheet having an electrogalvanized coating layer formed on a surface of a base steel sheet, in which the base steel sheet has a certain chemical composition, and a steel microstructure, in which a total area fraction of one or both of bainite containing carbides having an average grain diameter of 50 nm or less and tempered martensite containing carbides having an average grain diameter of 50 nm or less is 90% or more in the whole of the steel microstructure, and in which a total area fraction of one or both of the bainite containing and the tempered martensite containing carbides is 80% or more in a region from the surface of the base steel sheet to a position located at ? of a thickness of the base steel sheet, and diffusible hydrogen in steel in an amount of 0.20 mass ppm or less.

A steel alloy intended for cutting applications and hot working tools, comprising, in weight percent (wt. %), C: 0.40-1.2 wt. %, Si: 0.30-2.0 wt. %, Mn: max 1.0 wt. %, Cr: 3.0-6.0 wt. %, Mo: 0-4.0 wt. %, W: 0-8.0 wt. %, wherein (Mo+W/2)3.5 wt. %, Nb: 0-4.0 wt. %, V: 0-4.0 wt. %, wherein 1.0 wt. %(Nb+V)4.0 wt. %, Co: 25-40 wt. %, S: max 0.30 wt. %, N: max 0.30 wt. %, the balance being Fe and unavoidable impurities.