Patent classifications
C21D2261/00
RAILWAY WHEEL
A railway wheel in which formation of a quenched layer can be suppressed in the production process is provided. The railway wheel according to the present embodiment has a chemical composition consisting of, in mass %, C: 0.80 to 1.15%, Si: 1.00% or less, Mn: 0.10 to 1.20%, P: 0.050% or less, S: 0.030% or less, Al: 0.005 to 0.190%, N: 0.0200% or less, Nb: 0.005 to 0.050%, Cr: 0 to 0.25%, and V: 0 to 0.12%, with the balance being Fe and impurities. In the microstructure of a rim part of the railway wheel, an area fraction of pro-eutectoid cementite is 0.1 to 1.5% and an area fraction of pearlite is 95.0% or more.
METHOD OF APPLYING A WEAR-RESISTANT COATING ON A YANKEE DRYING CYLINDER
A method of applying a long lasting wear-resistant coating on a Yankee drying cylinder (1), the method comprises: the step of providing a Yankee drying cylinder (1) having a cylindrical shell (2) with a circular cross-section and an outer surface (3); the step of performing a thermal spray operation to form a wear-resistant coating layer (4) on the outer surface of the Yankee drying cylinder (1) during which thermal spray operation coating feedstock (6) is fed to at least one spray device (5), heated to become plastic and/or semi-molten and/or molten and sprayed onto the outer surface (3) of the Yankee drying cylinder (1) to form the wear-resistant coating layer (4), the coating feedstock (6) for the thermal spray operation consisting of: 1.5 to 2.5 weight percent Al 0.0 to 0.2 weight percent Ti, 9.5 to 10.5 weight percent Si, 0.0 to 0.2 weight percent B, 12.5 to 14.2 weight percent Mo, 0.0 to 0.2 weight percent V, 0.0 to 0.2 weight percent C, 0.000 to 0.020 weight percent Cr, 4.5 to 6.0 weight percent Mn, 0.0 to 0.2 weight percent Mg, 0.0 to 0.2 weight percent Ni, 0.0 to 0.2 weight percent Nb, the remainder being iron and impurities.
Coatings and Yankee cylinders with such coatings are also disclosed.
STEEL SHEET, MEMBER, AND PRODUCTION METHODS THEREFOR
A steel sheet has a tensile strength of 1310 MPa or higher, a specified chemical composition, and a steel microstructure containing martensite at an area ratio of 70% or more, bainite at an area ratio of 30% or less, and ferrite and retained austenite at a total area ratio of 5% or less, in which, at a ¼ thickness position of the steel sheet, a number density of carbides having long axes of 0.5 μm or more is 60000 carbides/mm.sup.2 or less, in a ¼-to-¾ thickness region of the steel sheet, a number density of inclusion grains having equivalent circle diameters of 4.0 μm or more is 10 grains/mm.sup.2 or more and 30 grains/mm.sup.2 or less, and, in a surface-to-¼ thickness region of the steel sheet, a number density of inclusion grains having equivalent circle diameters of 4.0 μm or more is 27 grains/mm.sup.2 or less.
METHOD FOR MANUFACTURING A PART OF NITRIDED STEEL
A method for manufacturing a part of nitrided steel includes a step of nitriding the part. After nitriding, laser shocking is carried out on a surface of the nitrided part.
Manufacturing Method for Zirconium Alloy Tubular Products
Manufacturing method for zirconium alloy tubular products containing (% wt.): niobium—0.9-1.7; iron—0.10-0.20; oxygen—0.10-0.20; silicon—less than 0.02, carbon—less than 0.02, zirconium—the alloy base. The method includes melting an ingot by multiple vacuum arc remelting, mechanical processing of the ingot, heating, multi-stage hot forging for production of the forged piece, subsequent mechanical processing of the forged piece for production of tubular billets with vacuum thermal treatment, application of a protective coating, heating to a hot pressing temperature, hot pressing, removal of the protective coating, vacuum thermal treatment, multiple cold rolling steps with a total deformation degree of 58-74% per run and a tubular coefficient of Q=1.18-2.01, with intermediate vacuum thermal treatment in order to produce tubular products, and final vacuum thermal treatment being carried out at the final size with subsequent final finishing operations.
Hot and cold composite formed square and rectangular steel tube with thickened corners and production method
A hot and cold composite formed square and rectangular steel tube and a production method for the same are provided. The radius of an outer corner of the square and rectangular steel tube meets the following conditions: when t is less than or equal to 6 mm, R is greater than 0 and less than 2.0 t; when t is greater than 6 mm and less than or equal to 10 mm, R is greater than 0 and less than 2.5 t; when t is greater than 10 mm, R is greater than 0 and less than 3.0 t, wherein t is the wall thickness of a straight tube part of the square and rectangular steel tube; R is the radius of each of the outer corners of the four corners of the square and rectangular steel tube; and the wall thickness of each corner of the square and rectangular steel tube is between 1.0 t and 1.8 t.
High carbon steel track bushing
An example bushing has three portions along its radial direction including an inner portion most proximal to a central hole of the bushing, an outer portion most distal from the center hole, and a core portion between the inner portion and the outer portion. The core portion has a hardness that is less than the hardness of the inner portion or the outer portion of the bushing. The bushing may be formed using high carbon steel, which in some cases may be spheroidal cementite crystal structure. A rough bushing may be formed using the high carbon steel, followed by a direct hardening process, and an induction hardening process on the inner surface most proximal to the central hole of the bushing. The induction hardening on the inner surface may harden the outer portion while tempering the core portion of the bushing.
METHOD FOR PRODUCING HARDENED STEEL COMPONENTS WITH A CONDITIONED ZINC ANTI-CORROSIVE LAYER
A method for producing hardened steel components is provided. A sheet bar is cut from a galvanized strip made of a hardenable steel alloy. The sheet bar is cold-formed into a component blank and heated to a temperature that produces a structural change to austenite. The austenitized component blank is conveyed to a form hardening tool and is held in a form-fitting manner by an upper tool and lower tool, which have a shape essentially corresponding to that of the component blank. Due to the contact of the material of the component blank with the tools, the heat is removed from the steel material quickly enough that a martensitic hardening occurs. After the galvanization of the metal strip and before the temperature increase for achieving the austenitization, tin is applied to the surface of the strip, sheet blank, or component blank.
FERRITIC STAINLESS STEEL HAVING IMPROVED CORROSION RESISTANCE, AND METHOD FOR MANUFACTURING SAME
Disclosed are a ferritic stainless steel having improved corrosion resistance and a method for manufacturing same. The ferritic stainless steel according to an embodiment of the present disclosure includes, in percent by weight (wt%), 0.001 to 0.05% of C, 0.001 to 0.05% of N, 0.1 to 1.0% of Si, 0.1 to 1.0% of Mn, 12.0 to 22.0% of Cr, 0.01 to 1.0% of Ti, and 0.01 to 1.0% of Nb, with the balance being Fe and inevitable impurities, wherein an area ratio of microdefects is 2% or less, and a sulfur (S) content in a surface film within 5 mm from the surface is 10% or less.
System and method for producing a hardened and tempered structural member
System and methods relating to in-line heat-treating, hardening and tempering of material, such as for example, coiled steel into a roll-formed, hardened and tempered structural member having uniform or different targeted properties in selected zones of the structural member. The different targeted properties may be achieved by heating and/or cooling the material subject to certain parameters.