Abstract: An object is to provide a metal-resin bonded member that is easy to manufacture and has high bonding strength. The metal-resin bonded member includes a metal body having an iron oxide layer on the surface and a resin body bonded to the metal body via the iron oxide layer. The iron oxide layer has a thickness of 50 nm to 10 ?m. The iron oxide layer comprises 60-40 at % Fe and 40-60 at % O at the outermost surface side. The iron oxide layer contains magnetite (Fe3O4). The iron oxide layer is formed by heating the surface of an iron-based substrate at 200-850° C. in an oxidation atmosphere. The resin body is composed of polyphenylene sulfide (PPS). The bonding of the metal body and the resin body via the iron oxide layer can be carried out by insert molding, thermal adhesion utilizing friction heating, etc.

Abstract: The controlled cooling of previously heated and substantially straight steel wires of diameter more than 3.5 mm to a predetermined temperature including the steps: guiding the wires along individual paths through first coolant bath having bath liquid of water and a stabilizing additive, the bath liquid and the wires create a steam film around each wire along individual paths; directing an impinging liquid immersed inside first coolant bath towards the wires over a length along individual paths to cool down the wires, the impinging liquid decreases the thickness of the steam film or destabilizes the steam film, increasing speed of cooling over the length along individual paths; guiding the wires along individual paths out of the first coolant bath to be cooled down in air; after the further cooling, guiding the wires along individual paths through second coolant bath.

Abstract: The invention relates to a method and an apparatus for the targeted heat treatment of specific component zones of a steel component. A predominantly austenitic structure can be created in the steel component in one or more first regions, from which, by quenching, a majority martensitic microstructure can be created; and in one or more second regions, a majority bainitic microstructure can be created, wherein the steel component is initially heated in a furnace to a temperature above the AC3 temperature, the steel component is subsequently transferred into a treatment station, and can cool down during the transfer, and in the treatment station, the one or more second regions of the steel component are cooled down to a cooling finish temperature ?2 during a treatment time.

Abstract: In the present invention, a flat emitter is formed by the formation of emitter material wires into a unitary non-porous flat emitter structure. The wires are formed with increased yield and tensile strength as a result of the manner of the formation of the emitter material or metal into the wires that is transferred to the flat emitter. To form the flat emitter, the wires are encapsulated and subjected to sufficient temperatures and pressure in a hot isostatic pressing treatment/process to increase the density of the wires into a solid sheet without the presence of voids or pores in the sheet. In forming the emitter sheet in this manner, the strength properties from the wires are retained within the sheet to provide the emitter with increased creep resistance and a consequently longer useful life in the x-ray tube.

Abstract: A wire rod according to an aspect of the present invention has a predetermined chemical composition, a solute N is 0.0015% or less, a structure in an area from a surface of the wire rod to a depth of ¼ of a diameter of the wire rod in a cross section thereof includes 90.0 area % or more of pearlite, and 0 to 10.0 area % in total of bainite and ferrite, a total amount of martensite and cementite in the area from the surface of the wire rod to the depth of ¼ of the diameter of the wire rod is limited to 2.0 area % or less, and the calculated maximum size of TiN-type inclusions in a surface layer area of the wire rod is 50 ?m or less.

Abstract: An attachment assembly for the disc of a mobile agricultural device, including a washer configured to attach to a disc of the mobile agricultural device. The washer may be attached to a center location of the disc. The washer is operatively connected to a deflector bar. The deflector bar substantially prevents debris from accumulating between the disc and a fertilizer assembly attached to the disc, as the disc rotates. The deflector bar in other embodiments, may be directly connected to a fertilizer assembly, rather than to the washer.

Abstract: This case hardening steel has a chemical composition including, by mass %: C: 0.1 to 0.6%; Si: 0.02 to 1.5%; Mn: 0.3 to 1.8%; P: 0.025% or less; S: 0.001 to 0.15%; Al: over 0.05 to 1.0%; Ti: 0.05 to 0.2%; N: 0.01% or less; and O: 0.0025% or less, and further including, by mass %, one or more of Cr: 0.4 to 2.0%, Mo: 0.02 to 1.5%, Ni: 0.1 to 3.5%, V: 0.02 to 0.5%, and B: 0.0002 to 0.005%, and the balance consisting of iron and unavoidable impurities.

Abstract: A method of producing a high tenacity metal wire material having improved bending and torsional properties as well as high toughness and excellent fatigue resistance is provided without losing tenacity and elongation property. In the method, when a heat treatment is performed at a temperature range of 90-300° C. on a metal wire material of high-carbon steel containing 0.5-1.1% by mass of carbon atoms and having a processing strain of 2.5 or greater and tensile strength of 3,000 MPa or greater, a relationship between heat treatment time t(s) and heat treatment temperature T(K) at said temperature range represented by the equation: 0.1?Ln(t)?10100/T+20?11 is satisfied.

Abstract: Fatigue damage resistant metal or metal alloy wires have a submicron-scale or nanograin microstructure that demonstrates improved fatigue damage resistance properties, and methods for manufacturing such wires. The present method may be used to form a wire having a nanograin microstructure characterized by a mean grain size that is 500 nm or less, in which the wire demonstrates improved fatigue damage resistance. Wire manufactured in accordance with the present process may show improvement in one or more other material properties, such as ultimate strength, unloading plateau strength, permanent set, ductility, and recoverable strain, for example. Wire manufactured in accordance with the present process is suitable for use in a medical device, or other high end application.

Abstract: A high-carbon steel wire has as steel composition: a carbon content ranging from 0.40 weight percent to 0.85 weight percent, a silicon content ranging from 1.0 weight percent to 2.0 weight percent, a manganese content ranging from 0.40 weight percent to 1.0 weight percent, and a chromium content ranging from 0.0 weight percent to 1.0 weight percent. The remainder is iron. This steel wire has as metallurgical structure a volume percentage of retained austenite ranging from 4 percent to 20 percent, while the remainder is tempered primary martensite and untempered secondary martensite. The steel wire is obtained by partitioning after quenching.

Abstract: The present invention relates to a method for heat treatment of a columnar work. In order to provide the method for heat treatment of a columnar work being able to attain a high productivity, a reduction of cost, and an improvement of quality, as compared with the prior art, the method for heat treatment of a columnar work of the present invention includes a quench-hardening step and a tempering step being carried out after the quench-hardening step, the quench-hardening step includes a first quench-hardening step and a second quench-hardening step being carried out after the first quench-hardening step, the entire region of the columnar work from an outer circumferential surface to a core thereof, or a partial region thereof, is heated up to a temperature not lower than a transformation temperature Ac3, and then, the work is quench-hardened.

Abstract: The present invention provides a wire rod with a composition at least including: C: 0.95-1.30 mass %; Si: 0.1-1.5 mass %; Mn: 0.1-1.0 mass %; Al: 0-0.1 mass %; Ti: 0-0.1 mass %; P: 0-0.02 mass %; S: 0-0.02 mass %; N: 10-50 ppm; O: 10-40 ppm; and a balance including Fe and inevitable impurities, wherein 97% or more of an area in a cross-section perpendicular to the longitudinal direction of the wire rod is occupied by a pearlite, and 0.5% or less of an area in a central area in the cross-section and 0.5% or less of an area in a first surface layer area in the cross-section are occupied by a pro-eutectoid cementite.

Abstract: A high carbon steel wire material which is made of high carbon steel as a raw material for wire products such as steel cords, bead wires, PC steel wires and spring steel, allows for these wire products to be manufactured efficiently at a high wire drawing rate and has excellent wire drawability and a manufacturing process thereof. This high carbon steel wire material is made of a steel material having specific contents of C, Si, Mn, P, S, N, Al and O, and the Bcc-Fe crystal grains of its metal structure have an average crystal grain diameter (Dave) of 20 ?m or less and a maximum crystal grain diameter (Dmax) of 120 ?m or less, preferably an area ratio of crystal grains having a diameter of 80 ?m or more of 40% or less, an average sub grain diameter (dave) of 10 ?m or less, a maximum sub grain diameter (dmax) of 50 ?m or less and a (Dave/dave) ratio of the average crystal grain diameter (Dave) to the average sub grain diameter (dave) of 4.5 or less.

Abstract: A method and device for cooling a wire. The device includes a block of material having a very high thermal capacity with a channel adapted for allowing passage of a wire to be cooled and at least one conduit for circulation of a cooling fluid, and at least one nozzle for injecting a turbulent fluid jet towards the wire to be cooled. The turbulent jet is capable of producing necessary cooling, thus avoiding the need for using conventional lead baths.

Abstract: The present invention aims at providing a method for production of a steel product which surely retains scale during cooling, storage, and transportation and permits scale to scale off easily at the time of mechanical descaling and pickling that precede the secondary fabrication. The steel product is produced by heating and hot rolling a steel billet and spraying the hot-rolled steel product with steam and/or water mist having a particle diameter no larger than 100 ?m, for surface oxidation.

Abstract: The invention provides wire rod excellent in drawability and steel wire made from the wire rod as starting material with high productivity at good yield and low cost. A hard steel wire rod of a specified composition is hot rolled, the hot-rolled steel is coiled in a specified temperature range, and the coiled steel is subjected to patenting at a predetermined cooling rate, thereby affording a high-carbon steel wire excellent in workability. It is high-strength steel wire excellent in drawability comprising a pearlite structure of an area ratio of 97% or greater and the balance of non-pearlite structures including bainite, degenerate-pearlite and pro-eutectoid ferrite and having a pearlite block size of not less than 20 ?m and not greater than 45 ?m. The invention also provides a high-carbon steel wire excellent in ductility, which is manufactured by subjecting the wire rod to intermediate patenting and cold drawing and has a tensile strength of 2800 MPa or greater.

Abstract: A high dimensional cored wire is provided containing de-oxidant material arranged in a core of the wire, the de-oxidant material being in finely divided granular or powdery form coated with a protective coating material, the diameter of the cored wire varying between 13 and 40 mm. A process for manufacturing the wire is also provided.

Abstract: The invention provides wire rod excellent in drawability and steel wire made from the wire rod as starting material with high productivity at good yield and low cost. A hard steel wire rod of a specified composition is heated in a specified temperature range to conduct post-reaustenization patenting and thereby obtain a high-carbon steel wire excellent in ductility that has a pearlite structure of an area ratio of 97% or greater and the balance of non-pearlite structures including bainite, degenerate-pearlite and pro-eutectoid ferrite and whose fracture reduction of area RA satisfies Expressions (1), (2) and (3) below: RA?RAmin??(1), where RAmin=a?b×pearlite block size (?m), a=?0.0001187×TS (MPa)2+0.31814×TS (MPa)?151.32??(2) b=0.0007445×TS (MPa)?0.3753??(3).

Abstract: A wire rod which is mainly composed of pearlite and has an area fraction of 5% or less of a non-pearlite structure composed of pro-eutectoid ferrite, degenerate-pearlite or bainite in a section, or has an area fraction of 10% or less of a non-pearlite structure in a portion from the surface to a depth of 100 ?m.

Abstract: A wire rod or a steel wire of a bamboo nano-structure, whose mean grain diameter in a C-direction section is 200 nm or smaller, is prepared by applying a hot or warm working and additionally applying a cold working to a steel and next, by performing a forging, by a tool or a die such as cold pressure production, to a section, of a desired, limited site, other than a section parallel to an L-direction, an equiaxed nano-structure, whose mean grain diameter is 200 nm or smaller, is formed in this site. As a typical example of a formed article, there is enumerated a high strength micro screw in which a shaft outer diameter is 1.6 mm or smaller, a surface layer part of a head part recess has equiaxed nano-structure and a hardness Hv?300, and a screw main body portion has bamboo nano-structure and a hardness Hv?250.

Abstract: A method for the production of steels is provided. A heat treatment is carried out, in which the steel is hardened in water twice at different high temperatures, and subsequently subjected to an annealing treatment. It has been shown that the steel 26NiCrMoV14-5 has a high subzero toughness. In one aspect, the steel is usable down to a temperature of at least minus 170° C.

Abstract: A steel wire for a cold-formed spring according to the present invention contains a prescribed chemical component composition, wherein: a martensitic transformation start temperature MS1 shown by the following expression (1) is in the range from 280° C. to 380° C.; the austenite grain size number N of austenite grains is No. 12 or more; the grain boundary share of carbide precipitated along the austenite grain boundaries is 50% or less; the amount of retained austenite after austenitized and tempered is 20 vol. % or less; and the tensile strength is 2,000 MPa or more; MS1=550?361[C]?39[Mn]?20[Cr]??(1), where [C], [Mn] and [Cr] represent the contents (mass %) of C, Mn and Cr, respectively. Such a steel wire can: secure hot-rolling formability and subsequent drawability while aiming at higher strength and higher stress; moreover exhibit excellent corrosion resistance; and obtain a spring (mainly a suspension spring for an automobile) excellent also in fatigue strength which is a basic required characteristic.

Abstract: A heat treatment method of manufacturing high carbon bearing steel having excellent abrasion resistance and fatigue resistance, a steel wire rod for high carbon bearing steel subjected to the heat treatment, a manufacturing method of the steel wire rod, high carbon bearing steel manufactured by the heat treatment and a soaking method of a steel bloom used for manufacturing the steel wire rod. The heat treatment method of bearings includes the steps of: quenching a bearing-shaped steel part containing, by weight, 0.5% to 1.20% carbon and 1.0% to 2.0% silicon; and partitioning the quenched steel part at a temperature ranging from Ms?100° C. to Ms for at least 10 minutes, where Ms represents a temperature at which formation of martensite will start.

Abstract: The invention provides wire rod excellent in drawability and steel wire made from the wire rod as starting material with high productivity at good yield and low cost. A hard steel wire rod of a specified composition is heated in a specified temperature range to conduct post-reaustenization patenting and thereby obtain a high-carbon steel wire excellent in ductility that has a pearlite structure of an area ratio of 97% or greater and the balance of non-pearlite structures including bainite, degenerate-pearlite and pro-eutectoid ferrite and whose fracture reduction of area RA satisfies Expressions (1), (2) and (3) below: RA?Ramin??(1), where RAmin=a?b×pearlite block size (?m), a=?0.0001187×TS (MPa)2+0.31814×TS (MPa)?151.32??(2) b=0.0007445×TS (MPa)?0.3753??(3).

Abstract: Iron-based alloys and articles in strips, sheets, workpieces and the like are converted into high strength steel with a minimum of cost, time and effort, including producing dual phase materials. This is achievable by extremely rapid micro-treating of low, medium, and high carbon iron-based alloys and articles by rapid heating and rapid cooling at least a portion of the alloy/article. This heating step involves nearly immediately heating the iron-based alloy to a selected temperature above its austenite conversion temperature. Then, the alloy is immediately quenched, also at an extremely fast rate, on at least a portion of the iron-based alloy in a quenching unit adjacent the heating unit. This procedure forms high strength alloy in a desired area, depending upon where the treatment was performed.

Abstract: A cooling unit, a heating-cooling operation including a cooling unit, a rod or wire manufacturing system, a method for manufacturing a rod or wire, a method for heat treating of a rod or wire, a method for treating metal, a steel rod or steel wire, and a treated metal having an improved tensile strength are disclosed. The cooling unit includes at least one adaptable quenching zone and at least one adaptable soaking zone. The at least one adaptable quenching zone is capable of quenching to a soaking temperature. The at least one adaptable soaking zone is capable of maintaining substantially the soak temperature.

Abstract: A process for manufacturing plated-steel armor wires intended for reinforcement of flexible tubular pipes for transporting hydrocarbons, comprising a plating coating is intimately bonded, by high pressure, to a core made of hardenable steel with moderate mechanical properties, and then the plated wire obtained undergoes a rapid high-temperature hardening step followed by a tempering step.

Abstract: Disclosed is a hard-drawn spring which exhibits fatigue strength and sag resistance equal or superior to springs produced using an oil-tempered wire. The hard-drawn spring is produced using a steel wire containing 0.5 to 0.7 mass % of C, 1.0 to 1.95 mass % of Si, 0.5 to 1.5 mass % of Mn and 0.5 to 1.5 mass % of Cr, with the balance being Fe and inevitable impurities. In the steel wire, the number of carbides having circle-equivalent diameters of 0.1 ?m or more is 5 particles/100 ?m2 or less.

Abstract: A method for the production of steels is provided. A heat treatment is carried out, in which the steel is hardened in water twice at different high temperatures, and subsequently subjected to an annealing treatment. It has been shown that the steel 26NiCrMoV14-5 has a high subzero toughness. In one aspect, the steel is usable down to a temperature of at least minus 170° C.

Abstract: A method of cooling strip or wire products in which, subsequent to being annealed, the product is cooled to a temperature of about 20-50° C. below its oxidation temperature. The product is wound around a drum immediately downstream of an annealing path so that the product lies in mutually juxtaposed turns on the drum. It is thereafter unwound from the drum after a number of turns. The number of turns is such that the product is cooled to a desired temperature. The drum has a diameter that exceeds the diameter at which the product will be influenced mechanically by plastic deformation.

Abstract: The technology described herein provides a method and system to prevent iron oxide formation and decarburization during strand heat treating of a steel product without the subsequent required use of acid pickling, which has associated health and environmental risks. Additionally, this technology provides placing a coating, such as copper plating, to the surface of a steel wire prior to strand heat treating to avoid both iron oxide formation and decarburization through the surface of the steel wire by preventing interactions between the steel wire and the furnace atmosphere. To remove oxides formed by the plating metal, the oxides are chemically reduced by passing the steel wire through a reducing gas, electrolytically reduced by plating with the wire anodic, mechanically reduced through the use of brushes, or the like, or chemically reduced by acid pickling.

Abstract: A method of producing forgings includes the steps of: forming forgings from a steel wire rod; heating the forgings to a temperature range of 830˜900° C.; subjecting the forgings to first tempering at a temperature range of 100˜300° C. after the heating at 830˜900° C.; and subjecting the forgings to second tempering at a temperature range of 300˜400° C, after the first tempering. In the first tempering, the forgings are quenched in a salt bath having a temperature in the range of 100˜300° C., and are tempered for 60˜130 minutes. In the second tempering, the forgings are quenched in a salt bath having a temperature in the range of 300—400° C., and are tempered for 30˜150 minutes.

Abstract: An oil-tempered wire for a cold-formed coil spring having a quality equivalent of or higher than a hot-formed coil spring is provided. A cold-formed coil spring made from the oil-tempered wire is also provided. Material used is the steel which contains, in weight percentage, 0.35 to 0.55% C, 1.8 to 3.0% Si, 0.5 to 1.5% Mn, 0.5 to 3.0% Ni, and 0.1 to 1.5% Cr. The ferrite fraction in the microscopic structure of this material is set to 50% or less. Hot rolled wire is cold drawn with a predetermined reduction of area, and a heat treatment using high frequency induction heating is conducted. It is preferable to set the maximum heating temperature between 900° C. to 1020° C. (favorably 950° C.) and holding time between 5 to 20 seconds. It is preferable to make the oil tempered material to have the grain size number of 9 or more, and the tensile strength from 1830 to 1980 MPa.

Abstract: The high carbon steel wire rod contains 0.65% to 1.20% of C, 0.05% to 1.2% of Si, 0.2% to 1.0% of Mn, and 0.35% or less (including 0%) of Cr, further contains P and S each in an amount restricted to 0.02% or less, where 80% or more of the metal structure is constituted by a pearlite structure; and an average tensile strength TS and an average lamellar spacing ? of the high carbon steel wire rod show the relation of TS?8700/?{square root over ( )}(?/Ceq)+290 in which Ceq=% C+% Mn/5+% Cr/4. The high carbon steel wire rod can omit a patenting treatment before or during wire drawing, is superior in wire drawability, and exhibits a low drawing resistance in a wire drawing die in an as-hot-rolled state.

Abstract: Disclosed is a method for patenting at least one steel wire, according to which the temperature is increased at least to a level at which the steel austenitizes, followed by quenching in a liquid medium by directing the wire through at least one curtain of cooling liquid so as to obtain a cooling temperature that lies below the austenitizing temperature, the liquid flowing in a turbulent manner substantially perpendicular to the wire, followed by an isothermal stage during which the wire is maintained at a constant temperature allowing pearlitic transformation. The inventive method is characterized by the fact that additionally, a number of successive curtains can be specifically adjusted so as to obtain the temperature which allows pearlitic transformation and is to be kept constant during the isothermal stage as the cooling temperature through the cooling process in a liquid medium, and the isothermal stage immediately follows the cooling process in a liquid medium.

Abstract: The very thin, high carbon wire is 0.05 to 0.50 mm in diameter and comprises, in mass %, 0.90-1.20% of C, 0.05-1.2% of Si, 0.2-1.0% of Mn, and 0.0050% or less of N, with the balance being iron and impurities. In a differential scanning thermal analysis curve A of the steel wire, the steel wire has an exothermic peak X in the temperature range of 60° to 130° C., and a maximum height h of the exothermic peak X relative to a reference line Y joining the point of 60° C. and the point of 130° C. in the differential scanning thermal analysis curve is set at 5 ?W/mg or more. The very thin, high carbon steel wire is free of delamination in high-speed stranding and superior in both strength and ductility.

Abstract: A steel wire of pearlite structure containing 0.8-1.0 mass % of C and 0.8-1.5 mass % of Si is disclosed. In the cross section of the steel wire the difference in average hardness between a region up to 100 ?m from the surface thereof and a deeper region is within 50 in micro-Vickers hardness. The steel wire is manufactured by working a wire rod having the abovementioned chemical composition through shaving, patenting and drawing processes, then strain-relief annealing the resultant wire, and thereafter subjecting the thus annealed to a shot peening process. The steel wire has a high heat resistance and a high fatigue strength, and can be produced through a drawing process without applying a quenching and tempering process.

Abstract: The present invention relates to a method of forming a coil of spring wire by winding a wire into a coil spring formed of a plurality of rings of the wire wherein each of the rings has a substantially constant strain rate. The forming speed of the wire being wound is controlled so that each of the rings has a substantially constant strain rate and minimum work hardening occurs.

Abstract: The present invention provides a steel wire rod excellent in scale peelability for mechanical descaling, and a manufacturing method thereof. The steel wire rod in accordance with the present invention has: a base metal portion formed of a steel containing C in an amount of not more than 1.1% and Si in an amount of 0.05 to 0.80% on a mass % basis as components; and a scale layer deposited on the surface of the base metal portion, wherein the Si average concentration in the interface portion of the scale with the base metal portion is not less than 2.0 times the Si content of the base metal portion.

Abstract: A double tapered steel wire (S) is evenly heat treated over the entire length thereof. The wire (S) has its constant-diameter straight portion (21, 24) disposed between its opposite end tapered portions (22, 23) each tapered down to its reduced-diameter outer end. In heat treatments, a diameter of the wire (S) is continuously detected by a detection means (3, 6), so that the amount of energy of induction heating applied to the wire (S) is controlled by a control unit (12) in a manner such that the amount of the energy is proportional to a wire diameter of the wire (S) having been detected, whereby heat applied to the wire (S) varies over the entire length of the wire (S). As a result, the wire (S) is quenched and tempered over its entire length in a manner such that the wire (S) thus heat treated has its small-diameter portions (24) and its large-diameter portion (21) differ from each other in tensile strength.

Abstract: To achieve a drawn wire with a tensile strength defined by the equation of Y=Yo exp(A2?d) wherein Y is the tensile strength in MPa (N/mm2), Yo is the strength of as patented wire, A2 is a coefficient dependant on wire chemistry and drawing conditions, and ?d is a total true drawing strain, a high carbon steel wire contains 0.95 to 1.3% carbon and a combination of chromium, manganese, silicon, cobalt, niobium, and boron is processed such that the bright wire of an intermediate diameter has a structure void of micro cracks, patented to produce a desired microstructure with defined inter-lamella spacing and austenite grain, coated with brass, and fine drawn with an optimized die draft schedule at a specified true strain.

Abstract: A process for thermomechanical treatment of steel for torsionally-strained spring elements, the initial material being heated with a heating rate of at least 50 K/s and austenitized, and then, being formed in at least one forming step with the formed product being quenched to below the martensite temperature to martensite and then tempered. To improve the strength or toughness properties of the spring steel in the strain direction of the torsionally strained spring elements so that the increase of vibration strength is considerable, the initial material is heated to a temperature above the recrystallization temperature and then formed at such a temperature, that dynamic and/or static recrystallization of the austenite occurs, and that the recrystallized austenite of the formed product is quenched.

Abstract: A steel wire rods and bars for machine structural use having, in the as-hot-rolled state, the same cold workability as a conventional steel wire rods and bars subjected to softening annealing after hot rolling, and a production method thereof are provided. This hot-rolled wire rods and bars usable for machine structural use without annealing comprises, in terms of mass %, C: 0.1 to 0.5%, Si: 0.01 to 0.5%, Mn: 0.3 to 1.5% and the balance of Fe and unavoidable impurities and if desired, comprises strengthening elements, wherein the microstructure of steel is composed of ferrite and pearlite, the ferrite grain size is No. 11 or more as defined in JIS G 0552, a granular carbide having an equivalent-circle diameter of 2 ?m or less and an aspect ratio of 3 or less is contained in an area ratio of 5 to 40%, and the steel wire rods and bars has a tensile strength TS (MPa)?573×Ceq+257 and a reduction of area RA (%)??23×Ceq+75 (wherein Ceq=C+Si/7+Mn/5+Cr/9+Mo/2).

Abstract: A bar or wire product for use in cold forging, characterized in that it comprises a steel having the chemical composition, in mass %: C: 0.1 to 0.6%, Si: 0.01 to 0.5%, Mn: 0.2 to 1.7%, S: 0.001 to 0.15%, Al: 0.015 to 0.05%, N: 0.003 to 0.025%, P: 0.035% or less, O: 0.003% or less and balance: Fe and inevitable impurities, and it has, in the region from the surface thereof to the depth of the radius thereof×0.15, a structure wherein ferrite accounts for 10 area % or less and the balance is substantially one or more of martensite, bainite and pearlite, and the average hardness in the region from the depth of the radius thereof×0.5 to the center thereof is less than that of the surface layer thereof by 20 or more of HV; and a method for producing the bar or wire product.

Abstract: A steel wire, 0.10-0.40 mm in diameter, obtained by subjecting a high-carbon (0.70-0.90 wt. %) steel wire material to heat treatment and wire drawing, wherein its tensile strength and test values of special repeated torsional tests satisfy a predetermined relation; and a method of manufacturing the same. A high strength steel wire which has so high a ductility as to substantially prevent the wire from being broken even during wire twisting, and which rarely encounters a decrease in the ductility even after the wire has been subjected to age hardening by heating, is obtained, and a method of manufacturing the same is economical.

Abstract: Steel wires and steel rods with excellent cold forging properties and used in a manufacture of various machine components, which have relatively high strengths, are disclosed. The steel wires are produced by maintaining a product (n×YS) of a yield strength (YS) and a work hardening coefficient (n) obtained by a tensile test of the steel wire within a range of 4.0-11.0 kgf/mm2, without a need of additional quenching and tempering treatments after cold forging. There is no need to perform heating for spheroidizing annealing for a long time, and it is possible to produce quenched and tempered steel wires having excellent cold forging properties by quenching and tempering treatments in a short period of time.

Abstract: A high-carbon steel wire rod with superior drawability which has the chemical composition (in mass %) of C: 0.6-1.0%, Si: 0.1-1.5%, Mn: 0.3-0.9%, P: no more than 0.02%, S no more than 0.03%, N: no more than 0.005%, (optional Nb: 0.020-0.050% and V: 0.05-0.20%), with the remainder being Fe and inevitable impurities, and the structure which is characterized in that pearlite accounts for no less than 95 area % and pearlite has an average nodule diameter (P &mgr;m) no larger than 30 &mgr;m and an average lamella space (S nm) no smaller than 100 nm such that the value of F calculated by the formula below is larger than zero F=350.3/{overscore (S)}+130.3/{overscore (P)}−51.7.

Abstract: Steel wires and steel rods with excellent cold forging properties and used in a manufacture of various machine components, which have relatively high strengths, are disclosed. The steel wires are produced by maintaining a product (n×YS) of a yield strength (YS) and a work hardening coefficient (n) obtained by a tensile test of the steel wire within a range of 4.0-11.0 kgf/2, without a need of additional quenching and tempering treatments after cold forging. There is no need to perform heating for spheroidizing annealing for a long time, and it is possible to produce quenched and tempered steel wires having excellent cold forging properties by quenching and tempering treatments in a short period of time.

Abstract: [OBJECT] An oil-tempered wire for a cold-formed coil spring having a quality equivalent of or higher than a hot-formed coil spring is provided. A cold-formed coil spring made from the oil-tempered wire is also provided.

Abstract: According to the present invention, there is disclosed a heat treated high carbon or alloy steel wire and method of heat-treating the wire. The wire is produced by the steps of initially heating the high carbon or alloy steel wire to a temperature of about 1600 degrees F. to about 1800 degrees F. for between 10 seconds and 2 minutes; rapidly cooling the wire to an intermediate point temperature of between 400 to about 1000 degrees F.; holding the wire at the intermediate point temperature for about 2 minutes to about 40 minutes; and cooling the resulting wire to ambient temperature.