Abstract: An energy-storing container is made of a lightweight steel having the following chemical composition (in wt %): C 0.04-2%; Mn 14-30%; Al 1.5-12%; Si 0.3-3%; Cr 0.12-6%, and additionally one or more of the following elements: Ti, V, Nb, B, Zr, Mo, Ni, Cu, W, Co, P, N, each at up to 5% and in total at up to 10%, wherein the remainder is Fe including common steel tramp elements, wherein the concrete alloy composition is selected in order to limit the ??-martensite fraction before or after a forming process to no more than 3%, with the stipulation that the ??-martensite equivalent according to 0.1*wt % Mn+wt % C+0.05*wt % Si is between 3.4 and 10.5.

Abstract: A martensitic Cr-containing steel having excellent corrosion resistance, SSC resistance, and IGHIC resistance is provided. A martensitic Cr-containing steel according to the present invention includes: a chemical composition consisting of, by mass %, Si: 0.05 to 1.0%, Mn: 0.1 to 1.0%, Cr: 8 to 12%, V: 0.01 to 1.0%, sol. Al: 0.005 to 0.10%, with the balance being Fe and impurities, wherein an effective Cr amount defined by “Cr?16.6×C” is not less than 8%, and an Mo equivalent defined by “Mo+0.5×W” is 0.03 to 2%; a micro-structure wherein a grain size number of prior-austenite crystal grain is not less than 8.0; and a yield strength of less than 379 to 551 MPa, wherein a grain-boundary segregation ratio of Mo and W is not less than 1.5.

Abstract: Manufacturing a cold-rolled steel plate, having a steel slab having the chemical composition containing, on the basis of percent by mass, C from 0.03 to 0.08%, Si from 0 to 1.0%, Mn from 0.2 to 0.8%, P at 0.03% or less, S at 0.01% or less, and Al at 0.05% or less so as to satisfy the following: formula (1) and at least one of Nb from 0.03 to 0.4%, V from 0.01 to 0.3%, and Ti from 0.01 to 0.3% so as to satisfy the following formula (2), with a residue being formed of Fe and unavoidable impurities. The steel slab is heated to 1200° C. or more and hot rolled to form a hot-rolled steel plate, which is wound from 550 to 700° C. to form a hot-rolled coil, and the hot-rolled coil is cold rolled or annealed and cold rolled, obtaining cross-sectional hardness from 200 to 350 HV.

Abstract: A low-alloy steel pipe includes C: 0.15% to less than 0.30%, Si: 0.05 to 1.00%, Mn: 0.05 to 1.00%, P: at most 0.030%, S: at most 0.0050%, Al: 0.005 to 0.100%, O: at most 0.005%, N: at most 0.007%, Cr: 0.10% to less than 1.00%, Mo: 1.0% to not more than 2.5%, V: 0.01 to 0.30%, Ti: 0.002 to 0.009%. Nb: 0 to 0.050%, B: 0 to 0.0050%, Ca: 0 to 0.0050%, Mo/Cr?2.0, and the balance being Fe and impurities. The pipe has a crystal grain size number of 7.0 or more, 50 or more particles of cementite based on equivalent circle diameter and area of the matrix, M2C-based alloy carbide in a number density of not less than 25/?m2, and a yield strength of 758 MPa or more.

Abstract: Identifying a stable phase of a binary alloy comprising a solute element and a solvent element. In one example, at least two thermodynamic parameters associated with grain growth and phase separation of the binary alloy are determined, and the stable phase of the binary alloy is identified based on the first thermodynamic parameter and the second thermodynamic parameter, wherein the stable phase is one of a stable nanocrystalline phase, a metastable nanocrystalline phase, and a non-nanocrystalline phase.

Abstract: The invention discloses a drill pipe having ultra-high toughness and high strength and comprising the following chemical elements in mass percentage: C: 0.24-0.30%, Si: 0.1-0.5%, Mn: 0.7-1.5%, Cr: 0.7-1.5%, Mo: 0.5-0.75%, V: 0.01-0.10%, Nb: 0.01-0.05%, P?0.015%, S?0.005%, and the balance of Fe and unavoidable impurities; and a process of manufacturing the drill pipe having ultra-high toughness and high strength, comprising: heating the drill pipe as a whole to 900-950° C.; subjecting the inner surface of the drill pipe to axial-flow water-spray cooling and the outer surface of the drill pipe to laminar-flow water-spray cooling while controlling the amount of the water sprayed at thickened ends of the drill pipe and that along the pipe body to be different from each other; and controlling the tempering temperature to be 650-675° C. The inventive drill pipe having ultra-high toughness and high strength has a longitudinal full-size impact toughness at ?20° C. of at least 100 J and has a strength of 135 ksi.

Abstract: A manufacturing method of precision machine tool bearing with high precision stability includes the procedures: (1) microstructural stabilization of bearing body: by cold ring rolling, two liquid quenching, ultrasonic assisted multiple cryo-tempering treatment and stress ageing treatment, the bearing body with high microstructure stability can be obtained; (2) precision machining; (3) internal stress relaxation of bearing body: after precision machining, by executing magnetic treatment on the bearing body, bearing ring with high microstructure stability and low internal stresses can be obtained; and (4) bearing assembly: finally precision machine tool bearing with high precision stability can be obtained.

Abstract: A high-strength hot-dip galvanized steel sheet having a surface coated with a hot-dip galvanized coating, the steel sheet having a chemical composition comprising C: more than 0.10% and less than 0.18%, Si: 0.01 to 1.00%, Mn: 1.5 to 4.0%, P: 0.100% or less, S: 0.020% or less, Al: 0.010 to 0.500%, Cr: 0.010 to 2.000%, Nb: 0.005 to 0.100%, Ti: 0.005 to 0.100%, B: more than 0.0005% and 0.0030% or less, and Fe and incidental impurities, and a method for producing the same. The steel sheet has a microstructure including ferrite having an area fraction in the range of 0 to 10%, martensite having an area fraction in the range of 15 to 60%, tempered martensite having an area fraction in the range of 20 to 50%, and bainitic ferrite having an area fraction in the range of 20 to 50%.

Abstract: A non-oriented electrical steel sheet containing: in mass%, C: 0.005% or less; Si: 0.1% to 2.0%; Mn: 0.05% to 0.6%; P: 0.100% or less; and Al: 0.5% or less, in which 10 pieces/?m3 or less in number density of non-magnetic precipitate AlN having an average diameter of 10 nm to 200 nm are contained, and an average magnetic flux density B50 in a rolling direction and in a direction perpendicular to rolling is 1.75 T or more. This non-oriented electrical steel sheet can be manufactured by two methods of a method of performing hot rolling annealing at a temperature of 750° C. to an Ac1 transformation point and a method of setting a coil winding temperature to 780° C. or higher and performing self annealing.

Abstract: There are provided a steel sheet for resistance to composite corrosion from sulfuric acid and hydrochloric acid, having excellent wear resistance and surface quality, and a method of manufacturing the same. The steel sheet having excellent surface qualities may be provided by improving resistance to erosion occurring due to coal cinders to increase a lifespan thereof and securing excellent resistance to composite corrosion from sulfuric acid and hydrochloric acid. Wear resistance may be significantly increased by adding P, and in order to solve a problem in that wear resistance is deteriorated due to the addition of P, a component system and a hot rolling process condition may be controlled, thereby forming a corrosion resistant layer having excellent corrosion resistance.

Abstract: A cold rolled and annealed martensitic steel sheet is provided. The steel sheet includes by weight percent, 0.30?C?0.5%, 0.2?Mn?1.5%, 0.5?Si?3.0%, 0.02?Ti?0.05%, 0.001?N?0.008%, 0.0010?B?0.0030%, 0.01?Nb?0.1%, 0.2?Cr?2.0%, P?0.02%, S?0.005%, Al?1%, Mo?1% and Ni?0.5%. The remainder of the composition includes iron and unavoidable impurities resulting from melting. The microstructure is 100% martensitic and a prior austenite grain size is lower than 20 ?m. The steel sheet has a delayed fracture resistance of at least 24 hours during an acid immersion U-bend test. A method, part, structural member and vehicle are also provided.

Abstract: The present invention relates to a hot-rolled steel sheet applied as a material for home appliances, vehicles, or the like and, more specifically, to a hot-rolled steel sheet having excellent workability and anti-aging properties and a method for manufacturing the same. To this end, the present invention uses ultra-low carbon Al-killed steel so as to optimize the alloying elements thereof and the manufacturing conditions, thereby providing hot-rolled steel sheets having both excellent workability and anti-aging properties.

Abstract: An electric resistance welded steel pipe for an oil well includes in terms of mass %: 0.02 to 0.14% of C, 0.05 to 0.50% of Si, 1.0 to 2.1% of Mn, 0.020% or less of P, 0.010% or less of S, 0.010 to 0.100% of Nb, 0.010 to 0.050% of Ti, 0.010 to 0.100% of Al, and 0.0100% or less of N. Contents of Cu, Ni, Cr, Mo, V, and B are 0 to 0.50%, 0 to 1.00%, 0 to 0.50%, 0 to 0.30%, 0 to 0.10%, and 0 to 0.0030%, respectively. Remainder consisting of Fe and unavoidable impurities. In a case that a full thickness specimen is subjected to a pipe axis direction tensile test, a tensile strength is 780 MPa or more, 0.2% proof stress/tensile strength is 0.80 or more, and 2% flow stress/tensile strength is from 0.85 to 0.98.

Abstract: A method of manufacturing a galvanized steel sheet having a composition containing, by mass %, C: 0.05% or more and 0.5% or less, Si: 0.01% or more and 2.5% or less, Mn: 0.5% or more and 3.5% or less, P: 0.003% or more and 0.100% or less, S: 0.02% or less, Al: 0.010% or more and 0.5% or less, B: 0.0002% or more and 0.005% or less, Ti: 0.05% or less, a relationship of Ti>4N being satisfied, and the balance comprising Fe and inevitable impurities, and a microstructure containing 60% or more and 95% or less of tempered martensite in terms of area ratio and 5% or more and 20% or less of retained austenite in terms of area ratio.

Abstract: The present invention provides a cold-rolled and annealed Dual-Phase steel sheet having strength from 980 to 1100 MPa and a breaking elongation greater than 9%. The composition includes the contents being expressed by weight: 0.055%?C?0.095%, 2%?Mn?2.6%, 0.005%?Si?0.35%, S?0.005%, P?0.050%, 0.1?Al?0.3%, 0.05%?Mo?0.25%, 0.2%?Cr?0.5%, Cr+2Mo?0.6%, Ni?0.1%, 0.010?Nb?0.040%, 0.010?Ti?0.050%, 0.0005?B?0.0025%, and 0.002%?N?0.007%. The remainder of the composition includes iron and inevitable impurities resulting from the smelting. A manufacturing method is also provided.

Abstract: A method is disclosed for the operationally reliable production of a cold-rolled flat steel product of ?0.5 mm in thickness for deep-drawing and ironing applications. In the method, a steel melt which (in wt %) comprises up to 0.008% C, up to 0.005% Al, up to 0.043% Si, 0.15-0.5% Mn, up to 0.02% P, up to 0.03% S, up to 0.020% N and in each case optionally up to 0.03% Ti and up to 0.03% Nb and, as a remainder, iron and unavoidable impurities, is, with the omission of a Ca treatment, subjected to a secondary metallurgical treatment which, in addition to a vacuum treatment, comprises a ladle furnace treatment and during which the steel melt to be treated is kept under a slag, the Mn and Fe contents of which are, in sum total, <15 wt %. From the steel melt, a thin slab or a cast strip are produced, which are subsequently hot-rolled to form a hot strip with a thickness of <2.5 mm and wound to form a coil. Subsequently, the hot strips are cold-rolled to form a flat steel product of up to 0.5 mm in thickness.

Abstract: A method of making weathering steel by preparing a molten melt producing an as-cast carbon alloy steel strip with a corrosion index of at least 6.0 comprising, by weight, 0.02%-0.08% carbon, <0.6% silicon, 0.2%-2.0% manganese, <0.03% phosphorus, <0.01% sulfur, <0.01% nitrogen, 0.2%-0.5% copper, 0.01%-0.2% niobium, 0.01%-0.2% vanadium, 0.1%-0.4% chromium, 0.08%-0.25% nickel, <0.01% aluminum, and the remainder iron and impurities. The molten melt is solidified and cooled into a cast strip ?4 mm in thickness in a non-oxidizing atmosphere. The strip is hot rolled in an austenitic temperature range above Ar3 to between 10% and 50% reduction, cooled at above 20° C./s and coiled below 700° C. to form a steel strip with a microstructure comprising bainite and acicular ferrite with more than 70% niobium in solid solution. Then, age hardening the strip resulting in a yield strength of at least 550 MPa and a total elongation of at least 8%.

Abstract: The invention relates to a method for producing an ultra high strength material with high elongation by work hardening an essentially nickel-free austenitic material and then subjecting the material to heat treatment in the temperature range between 200° C. and <1,100° C. within a period from 10 s to 10 minutes.

Abstract: A method for manufacturing a metal structure (130) for use in a downhole assembly comprises plastically deforming at least a portion of the metal structure (130); and heating at least the deformed portion of the metal structure to a temperature below its critical and/or transformation temperature. An assembly for performing the method comprises a production fixture (370) configured to receive the metal structure (130), wherein the production fixture is adapted to undergo heating to a temperature below and/or up to the critical and/or transformation temperature of the metal structure. By heating at least the deformed portion of the metal structure to a temperature below its critical and/or transformation temperature, the metal structure may undergo stress relief, which may help prevent undesirable movement of deformed portion, e.g. collet fingers of a catching apparatus, against the direction of deformation after impact(s) and/or shock(s) from moving objects, in use.

Abstract: A steel sheet includes a microstructure containing a volume fraction of 20% to 55% of ferrite having an average grain size of 7 ?m or less, a volume fraction of 5% to 15% of retained austenite, a volume fraction of 0.5% to 7% of martensite having an average grain size of 4 ?m or less, and a structure composed of bainite and/or tempered martensite and having an average grain size of 6 ?m or less, and a difference in nano-hardness between ferrite and the structure composed of bainite and/or tempered martensite being 3.5 GPa or less and a difference in nano-hardness between the structure composed of bainite and/or tempered martensite and martensite being 2.5 GPa or less.