Abstract: A fluid circulation heating roller according to an embodiment of the present invention includes a roller body having a hollow cylindrical shape, a rotation shaft extending from each of opposite end portions of the roller body and disposed in the same center line, multiple first ducts extending in an axial direction in the roller body so as to heat the outer circumferential portion of the roller body, multiple second ducts extending in the axial direction on the outer circumferential portion of the roller body, wherein the number of second ducts are the same as the number of first ducts, and an insert inserted into at least one of the first or second ducts and extending in the axial direction. The generation of turbulence flow of fluid can be suppressed and laminar flow can be induced, whereby it is possible to maintain fluid-flowing speed and facilitate steam circulation and heat transfer.

Abstract: Disclosed are a gear product having an enhance deposition surface and a deposition system for manufacturing the gear product. The gear product having a reinforced deposition surface according to the present disclosure includes: teeth in which valleys and crests are successively famed along an outer or inner circumference of a cylindrical body having a central rotation shaft; and a reinforced deposition layer, which is formed by radiating a laser beam in a coaxial nozzle system to be directed to the teeth and injecting powdered materials to be in contact with a radiation axis of the laser beam around the radiated laser beam such that the powdered materials are melted and integrated with a surface of the teeth.

Abstract: The present invention relates to a method for producing graphene on a face-centered cubic metal catalyst having a plane oriented in one direction, and more particularly to a method of producing graphene on a metal catalyst having the (100) or (111) crystal structure and a method of producing graphene using a catalyst metal foil having a single orientation, obtained by electroplating a metal catalyst by a pulse wave current and annealing the metal catalyst. The invention also relates to a method of producing graphene using a metal catalyst, and more particularly to a method of producing graphene, comprising the steps of: alloying a metal catalyst with an alloying element; forming step structures on the metal catalyst substrate in an atmosphere of a gas having a molecular weight of carbon; and supplying hydrocarbon and hydrogen gases to the substrate. On unidirectionally oriented metal catalyst prepared according to the present invention, graphene can be grown uniformly and epitaxially.

Abstract: The present invention relates to a method for producing graphene on a face-centered cubic metal catalyst having a plane oriented in one direction, and more particularly to a method of producing graphene on a metal catalyst having the (100) or (111) crystal structure and a method of producing graphene using a catalyst metal foil having a single orientation, obtained by electroplating a metal catalyst by a pulse wave current and annealing the metal catalyst. The invention also relates to a method of producing graphene using a metal catalyst, and more particularly to a method of producing graphene, comprising the steps of: alloying a metal catalyst with an alloying element; forming step structures on the metal catalyst substrate in an atmosphere of a gas having a molecular weight of carbon; and supplying hydrocarbon and hydrogen gases to the substrate. On unidirectionally oriented metal catalyst prepared according to the present invention, graphene can be grown uniformly and epitaxially.

Abstract: The present invention relates to a method for producing graphene on a face-centered cubic metal catalyst having a plane oriented in one direction, and more particularly to a method of producing graphene on a metal catalyst having the (100) or (111) crystal structure and a method of producing graphene using a catalyst metal foil having a single orientation, obtained by electroplating a metal catalyst by a pulse wave current and annealing the metal catalyst. The invention also relates to a method of producing graphene using a metal catalyst, and more particularly to a method of producing graphene, comprising the steps of: alloying a metal catalyst with an alloying element; forming step structures on the metal catalyst substrate in an atmosphere of a gas having a molecular weight of carbon; and supplying hydrocarbon and hydrogen gases to the substrate. On unidirectionally oriented metal catalyst prepared according to the present invention, graphene can be grown uniformly and epitaxially.

Abstract: The present invention relates to a method for producing graphene on a face-centered cubic metal catalyst having a plane oriented in one direction, and more particularly to a method of producing graphene on a metal catalyst having the (100) or (111) crystal structure and a method of producing graphene using a catalyst metal foil having a single orientation, obtained by electroplating a metal catalyst by a pulse wave current and annealing the metal catalyst. The invention also relates to a method of producing graphene using a metal catalyst, and more particularly to a method of producing graphene, comprising the steps of: alloying a metal catalyst with an alloying element; forming step structures on the metal catalyst substrate in an atmosphere of a gas having a molecular weight of carbon; and supplying hydrocarbon and hydrogen gases to the substrate. On unidirectionally oriented metal catalyst prepared according to the present invention, graphene can be grown uniformly and epitaxially.

Abstract: Disclosed is a wrought magnesium alloy having excellent strength and extrusion or rolling formability, and a method of producing the same. The wrought magnesium alloy comprises 0.1-1.5 at % group IIIa, 1.0-4.0 at % group IIIb, 0.35 at % or less of one selected from the group consisting of groups IIa, IVa, VIIa, IVb, and a mixture thereof, 1.0 at % or less of group IIb, and a balance of Mg and unavoidable impurities and thus has a second phase composite microstructure. The wrought magnesium alloy of the present invention has high strength, toughness, and formability in addition to the electromagnetic wave shield ability of magnesium. Accordingly, the wrought magnesium alloy is a material useful to portable electronic goods, such as notebook personal computers, mobile phones, digital cameras, camcorders, CD players, PDA, or MP3 players, automotive parts, such as engine room hoods, oil pans, or inner panel of door, or structural parts for airplane.

Abstract: An engine tappet of high abrasion resistance, whose surface is coated with a sintered layer. This sintered layer is prepared from a binder comprising about 50-100 wt % of nickel powder, about 0-45 wt % of Cr, about 0-35 wt % of Mo, about 0-10 wt % of Al, about 0-25 wt % of Co, about 0-10 wt % of Cu and inevitably mixed impurities; and from hard particles selected from the group consisting of carbides, nitrides, borides and the mixtures thereof. Also, there is provided an engine tappet which is coated with an alloy powder composition comprising about 44-88 wt % of WC, about 4-10 wt % of Co, about 15-50 wt % of Ni, about 5-20 wt % of Cr, about 0.5-4 wt % of B, about 2-4 wt % of Fe, about 0.5-4 wt % of Si, about up to 1.0 wt % of C and inevitably mixed impurities.

Abstract: The present invention relates to a wear resistant materials having excellent wear resistance and a method of manufacturing the materials, comprising a process that lugs are formed on surface by electro-sparking welding apparatus having a vibrator, and a process that coats solid lubricant layer having wear resistance on the said lugs (ref. FIG. 3).

Abstract: Erosion and wear resistant iron alloy, comprising: Cr 20.0-36.0% by weight, B 2.5-5.0% by weight, Mn 0.5-3.2% by weight, Si 0.05-0.6% by weight, Mo 0.3-2.5% by weight, V 0.05-0.3% by weight, Nb 0.03-0.3% by weight, P 0.5% by weight or less, C 0.05-0.3% by weight, and a trace of unavoidable impurities, which confers superior corrosion and wear resistance upon abraded or corroded portions by coating or molding.

Abstract: Disclosed is a manufacture and coating method of mechanical products using ferrous alloy in order to improve wear, corrosion, and heat resistances of the mechanical products which are exposed to friction and wear environments with or without lubricating conditions. The mechanical products of the invention include rotation contact parts such as bush and shaft in the inside of caterpillar roller, mechanical seal under high surface pressure, and drawing dice and plug under sliding friction stress. A ferrous alloy composition used for coating in the invention comprises Cr:18.0-42.0 wt %, Mn: 1.0-3.2 wt %, B:3.0-4.5 wt %, Si: 1.0-3.0 wt %, C: less than 0.3 wt %, inevitably incorporated impurities, and Fe for the rest of content. A ferrous alloy composition used for manufacturing bush type product comprises C: less than 4.5%, Si:2.5%, Mn:less than 2%, Cr:0.5-35%, and Fe for the rest of content.

Abstract: The present invention is concerned about high toughness and high strength untempered steel having the mechanical properties equivalent to or better than those of tempered steel and processing method thereof, more particularly, the high toughness and high strength untempered steel having the tensile strength higher than 90 kgf/mm.sup.2 with the impact toughness higher than 5 kgf-m/cm.sup.2 in the KS 3 specimen, and processing method thereof.