Abstract: A solid oxide fuel cell includes cathode electrode, a solid oxide electrolyte, and an anode electrode including a first sublayer and a second sublayer. The first sublayer is located between the electrolyte and the second sublayer. The first sublayer is composed of a doped ceria and the second sublayer is composed of a nickel containing phase and a ceramic phase including a doped ceria and scandia stabilized zirconia, such as scandia ceria stabilized zirconia.

Abstract: The present invention aims to provide a rare earth magnet having sufficiently excellent anticorrosion property. The rare earth magnet 1 according to the present invention to solve the above problems includes a magnet body 10 containing rare earth elements, a substantial amorphous layer 20 formed on a surface of the magnet body 10, and a protecting layer 30 on a surface of the amorphous layer 20, and the amorphous layer 20 contains material identical to main component elements of magnet material contained in the magnet body 10.

Abstract: A nickel based alloy coating and a method for applying the nickel based alloy as a coating to a substrate. The nickel based alloy comprises about 0.1-15% rhenium, about 5-55% of an element selected from the group consisting of cobalt, iron and combinations thereof, sulfur included as a microalloying addition in amounts from about 100 parts per million (ppm) to about 300 ppm, the balance nickel and incidental impurities. The nickel-based alloy of the present invention is applied to a substrate, usually an electromechanical device such as a MEMS, by well-known plating techniques. However, the plating bath must include sufficient sulfur to result in deposition of 100-300 ppm sulfur as a microalloyed element. The coated substrate is heat treated to develop a two phase microstructure in the coating.

Abstract: Quenching heat treatment is performed on a whole rocker arm bearing assembly in which shaft ends of a supporting shaft is fixed to inner peripheral edges of shaft end insertion holes of a pair of opposite sidewalls, and by the outer ring is rotatably supported on a raceway portion of an shaft intermediate portion of the supporting shaft through a plurality of rolling elements or directly, thereby manufacturing a rocker arm bearing apparatus.

Abstract: An aluminum-based welding filler wire is made with an aluminum alloy that contains between 0.1 and 6 wt. % titanium, including one portion in the form of TiB2 particles, TiC particles, or a combination thereof, and another portion in the form of free titanium. The filler wire can be used in welding aluminum-based materials.

Abstract: A woven, braided or knitted fabric structure includes wires of silver alloy, preferably a precipitation-hardened Ag Cu Ge alloy. The process for making a fabric structure may include providing silver wire having a temper of more than fully soft but less than half hardness, forming said wire into said structure and heating the structure to precipitation-harden the wire.

Abstract: In a method and system for an improved annealing furnace cooling and purging, atmosphere injection jets are provided in close proximity to a bottom of a tray carrying a lamination product in a cooling section. Atmospheric extraction tubes are also provided extracting atmosphere which is delivered to a high temperature variable speed fan which then outputs at a pressure side atmosphere to tubes having the injection jets. The system may be retrofit into an existing annealing furnace already having water cooled finned tubes and a recirculation fan in the cooling section. Cooling water tubes and a recirculating fan may also be provided in a purge vestibule located after an output from the cooling section for additional cooling.

Abstract: In an improved annealing furnace for laminations having a purge vestibule and an oxidation section, atmosphere injection tubes with atmosphere injection jets are provided in the oxidation section at a conveyor directly beneath trays conveying the laminations. Atmosphere extraction tubes are also provided along with a fan which draws atmosphere from the extraction tubes and provides a pressure output to the atmosphere injection tubes. The speed of the fan may be variable.

Abstract: A fixture and method for repairing superalloy articles. The fixture ideally holds the article in place if repairs are made. An interface between the fixture and the article facilitate transfer of heat between the article and the fixture so that the article can be differentially heat treated. A portion of the article extends from the fixture. This portion of the article, which may be repaired within the fixture or may be repaired elsewhere, is solution heat treated while in the fixture so that the area extending from the fixture is solutioned, while heat is transferred from the article through the fixture, thereby preventing the temperature of the portion of the article within the fixture from being elevated so as to modify its microstructure. The solutioned portion can then be heat treated, while in the fixture, to precipitation harden it as desired.

Abstract: In the manufacture of a physical quantity detector, such as a pressure sensor and a load sensor, comprising a cylindrical part of which one end is closed with a strain generating part and a sensor part formed on the strain generating part, the cylindrical part mentioned above is produced by melting an alloying material having a composition capable of yielding an amorphous alloy, injecting the resultant molten alloy into a metal mold, and cooling the molten alloy in the metal mold to confer amorphousness on the alloy. The metal mold is composed of a split mold having at least two split parts for forming a cavity and an insert pin to be inserted into the cavity so as to define the inner configuration of the cylindrical part, or further an insert core to be inserted into the mold so as to form the surface of the cavity corresponding to the surface of the strain generating part.

Abstract: Systems and methods for repairing Thermo-Span® gas turbine engine components are described herein. Embodiments of these methods minimize post-weld residual stresses in a weld repaired Thermo-Span® component by solution heat treating the component by heating the component to about 2000° F.±25° F., holding the component at about 2000° F.±25° F. for about one hour; and cooling the component to below about 700° F. at a rate equivalent to cooling in air; and precipitation heat treating the component by heating the component to about 1325° F.±25° F., holding the component at about 1325° F.±25° F. for about 8 hours, cooling the component to about 1150° F.±25° F. at a maximum rate of about 100° F./hour, holding the component at about 1150° F.±25° F. for about 8 hours, and cooling the component at a predetermined cooling rate. Dimensions of the fully-machined and weld repaired component are maintained during solution heat treating and precipitation heat treating via custom designed furnace tools.

Abstract: A method for annealing a structure formed by electrodeposition is provided, the method comprising providing the electrodeposition structure, the electrodeposition structure comprising an electroformed mold, the electroformed mold having a nominal thickness between and including 0.5 mm to 8.0 mm and having a melting temperature; heating the electrodeposition structure to a temperature between ambient temperature and the melting temperature of the electrodeposition structure; isostatically pressurizing the electrodeposition structure to a pressure above ambient pressure; cooling the electrodeposition structure to ambient temperature; and depressurizing the electrodeposition structure to ambient pressure.

Abstract: The present invention relates to the use of a pre-coating process, which utilizes metallic plating as a surface pre-treatment for a ferrous-alloy precursor prior to applying a corrosion-inhibiting coating to improve the overall corrosion protection of the pre-treated and pre-coated component. Preferably the ferrous-alloy precursor is a heat-treatable, precipitation-hardenable stainless-steel material and the pre-treatment is a cadmium or a zinc-nickel alloy plating without a subsequent chromate or phosphate seal finish.

Abstract: A process for producing a medical guide wire comprising a step S2, S5 for inserting the core wire and coil into a tubular die having the desired curved form, a step S3, S6 for heat-treating the core wire and coil in the die, a step 7 for removing oxide skin or films from the heat-treated core wire, a step S8 for assembling the obtained coil to the core wire, a step S9 for brazing or soldering an end of the coil to the core wire, a step S10 for grinding or sandering the obtained guide wire, and then a step for washing the guide wire.

Abstract: Disclosed is a brazing sheet product including a core metal sheet (1), on at least one side of the core metal sheet (1) a clad layer (2) made of an aluminium brazing alloy comprising silicon in an amount in the range of 4 to 14% by weight, and on at least one outersurface of the clad layer (2) a layer comprising iron or iron alloy (4), and on the outersurface of the layer comprising iron or iron alloy (4) a further layer (3) including a metal X, whereby X is selected from the group consisting of tin, zinc, bismuth, indium, antimony, strontium, titanium, manganese, copper, or combinations of two or more thereof. Also, disclosed is a method of manufacturing such a brazing product, and a brazed assembly including at least one component made of this brazing product.

Abstract: A method of joining workpieces using a solder alloy. The alloy contains either at least 1% or a maximum of about 10% by weight of an element or a mixture of elements selected from the group consisting of titanium, zirconium, hafnium, vanadium, niobium, and tantalum; either at least 0.01% or 0.01–10% by weight of an element or a mixture of elements selected from the group of the lanthanides (rare earths); either at least 0.5% or 0.5–10% by weight of an element or a mixture of elements selected from the group consisting of silver, copper, and indium; optionally either at least 0.01% or 0.01–1% by weight of gallium; and a remainder consisting of tin, lead, or of a mixture of tin and lead.

Abstract: A material and method for adhering at least two materials that includes the step of interposing at least one intermediate layer between the two materials and associated adhesion material. The materials to be adhered exhibit at least one characteristic dissimilarity and the intermediate material interposed contains at least one shape memory alloy, the shape memory alloy capable of exhibiting superelasticity.

Abstract: A golf club head is provided with a residual compressive stress layer on the inside surface of the club face using a peening treatment. The peening treatment also may remove material from the club head, such as unwanted alpha case on a titanium club head. The body of the club head further may be subjected to a peen treatment.

Abstract: An apparatus and method of manufacturing a wire mesh laminate includes wrapping a central core with multiple layers of mesh screen and a barrier layer having a higher melting point than the mesh screen to form a spool assembly. The spool assembly is then surrounded by an outer cover and is heated to sinter or fuse together the layers of mesh screen.

Abstract: A process for the production of thin walled parts of steel, wherein there are layers that are at least partly differently treatable relating to their strength and hardness qualities. This process can include creating a composite material from a plurality of different layers by connecting at least one core layer and at least one surface layer together. At least one layer of the core or surface layer is cast adjacent to another layer to form a composite material having an alloy gradient that is flat at each interface between any of the core layer or the surface layer. Next, the process can include deforming the composite material along a length of these layers. Finally the process can include heat treating the layers to transform the strength and hardness qualities of at least one of these layers.

Abstract: The present invention is directed to a process for preparing aluminum and aluminum alloy surfaces in heat exchangers for brazing by depositing thereon a kinetic sprayed brazing composition. The process simultaneously deposits monolith or composite coatings that can include all braze materials and corrosion protection materials used in the brazing of aluminum fins to plates and tubes in a single stage.

Abstract: An improved method of weldbonding utilizing inclusion bodies, placed directly between materials to be bonded or included in a weldbonding adhesive. The inclusion bodies maintain a gap between the materials to be welded which provides a gas releasing egress route to disperse the gas and gaseous byproducts produced during welding. This egress route substantially prevents the gases and gaseous byproducts from being expelled through the weld pool and the resultant degradation of the quality of the weld pool, particularly with coated materials, partial penetration welds, and such materials as 6000 series aluminum. The method further comprises an optional step of including a crack-reducing additive, applied either directly to the materials to be welded or included in the adhesive. A laser weldbonding embodiment may use a plurality of phased heat cycles to reduce weld imperfections, and enhance the effects of the adhesive and optional crack-reducing additive.

Abstract: A method of repairing a void on a nickel or cobalt base superalloy investment casting by vibrating the casting for a time before repairing the void, vibrating the casting while filling the void wherein the void is filled by repeatedly making incremental weld deposits of a superalloy filler material in the void using pulsed gas tungsten arc welding, and impinging each incremental deposit with a cooling gas after each incremental weld deposit is made and before the next incremental weld deposit is made, and vibrating the casting for a time after the void is filled.

Abstract: One object of the present invention is to provide a production method for a nuclear fuel assembly support grid that improves the corrosion resistance of welded parts without impairing the characteristics of the support grid so as to be able adequately withstand highly efficient operation. In order to achieve the object, the present invention provide a production method for a nuclear fuel assembly support grid comprising the steps of: assembling a plurality of straps in a grid form; welding intersections of each strap; and carrying out annealing thereafter to precipitate an intermetallic compound on the welded parts.

Abstract: A bright composite sheet product including a roll cast core and a clad material bonded to the core. The core is an aluminum alloy of the AA series 1XXX, 3XXX, 5XXX, or 8XXX, and the clad material contains at least 99.5 wt. % aluminum. The composite sheet products is particularly suited for use in lighting fixtures.

Abstract: This invention relates to a stainless steel gasket having markedly improved strength and fatigue properties due to precipitation strengthening. Its composition comprises C: at most 0.03%, Si: at most 1.0%, Mn: at most 2%, Cr: 16.0%-18.0%, Ni: 6.0%-8.0%, N: at most 0.25%, if necessary Nb: at most 0.30%, and a remainder of Fe and unavoidable impurities. After cold rolling, final annealing is carried out, and after a structure is formed of recrystallized grains with an average grain diameter of at most 5 ?m having an area ratio of 50-100% and an unrecrystallized portion having an area ratio of 0-50%, a metal gasket is formed by steps including temper rolling with a reduction of at least 30% to make the area ratio of a strain induced martensite phase at least 40%, and forming and heat treatment at 200-350° C.

Abstract: Martensitic stainless steel whose steel composition is restricted within a specific range for each element is provided. The scale layer formed on the surface of the base material consists of an inner layer scale mainly including FeCr2O4 and an outer layer scale having a thickness of not more than 20 ?m, which outer layer is deposited on the inner layer scale at a surface coverage of not less than 1% and not more than 15%. The application of rust preventive oil onto the surface of the steel ensures an excellent weather resistance during a long term, and therefore a martensitic stainless steel forming no rust either in the outdoor depository or in the indoor depository can be provided. The steel can be used to manufacture, not only steel pipes, but also steel plates, steel rods and others in a wide application field.

Abstract: High pressure cylinders comprising backing steel cylinders and tool steel liners are disclosed. An annealed tool steel liner is inserted into the backing steel cylinder, followed by heat treating to harden the tool steel liner. The tool steel liner may be provided as a single continuous tube, thereby avoiding problems associated with segmented liners. The high-pressure cylinders are suitable for use as plastic and rubber extruders injection molding cylinders and the like.

Abstract: A surface processing method and power transmission component includes refining a surface region of a metal from a first roughness to a second roughness less than the first roughness. A solid lubricous coating or a hard coating is then deposited on the surface region. The metal has a surface hardness above 50 Rc to reduce the risk that the metal will deform under the coating and leave the coating unsupported. The surface region of the metal may be transformed into a nitrogen-containing compound or solid solution surface region before the surface refining step and deposition of the coating.

Abstract: A material and method for adhering at least two materials that includes the step of interposing at least one intermediate layer between the two materials and associated adhesion material. The materials to be adhered exhibit at least one characteristic dissimilarity and the intermediate material interposed contains at least one shape memory alloy, the shape memory alloy capable of exhibiting -superelasticity.

Abstract: A coated nickel-base superalloy article, which is otherwise susceptible to the formation of a secondary reaction zone, is prepared by furnishing a nickel-base superalloy article substrate having thereon an initial aluminum-containing coating comprising an initial-coating additive zone and an initial-coating diffusion zone. The article is susceptible to the formation of the secondary reaction zone if heated to an elevated SRZ reaction temperature for an SRZ reaction period of time. The formation of the secondary reaction zone is avoided by first removing the initial-coating additive zone and the initial-coating diffusion zone, and thereafter depositing a subsequent aluminum-containing coating onto the article substrate. The subsequent aluminum-containing coating includes a subsequent-coating additive zone and a subsequent-coating diffusion zone.

Abstract: A family of extremely fine-grained alloys are used to make coatings or free-standing bodies having desirable properties for use as a heat-resistant and wear-resistant material. In an illustrative embodiment, the alloys are comprised of a multiplicity of alternate, microcrystalline or nanocrystalline films of tungsten metal and tungsten compound. The tungsten compound film may be comprised of a tungsten carbide or a tungsten boride. The tungsten films are the primary films. Their desirable characteristics, in addition to their very fine crystalline habit, per se, are the high strength, high hardness, high resilience, and high fracture energy which these fine crystallites foster. They may be manufactured by a chemical vapor deposition process in which reactive gas flows are rapidly switched to produce alternate films with abrupt hetero-junctions and thereby to produce the useful micro-crystalline habit. The unique synthesis method allows effective control of critical flaw size.

Abstract: An aluminum-coated structural member includes an Al—Si—Fe alloy layer formed on a steel substrate layer. The alloy layer includes a softer region having a hardness smaller than or equal to a hardness of the steel substrate layer, extends from the surface of the steel substrate layer toward a surface of the alloy layer, over a depth range greater than or equal to 50% of a thickness of the alloy layer. The Al—Si—Fe alloy layer has an oxide weight smaller than or equal to 500 mg/dm2.

Abstract: A method for annealing a structure formed by electrodeposition including providing the electrodeposition structure, the electrodeposition structure including an eletroformed mold, the electroformed mold having a nominal thickness between and including 0.5 mm to 8.0 mm and having a melting temperature; heating the electrodeposition structure to a temperature between ambient temperature and the melting temperature of the electrodeposition structure; isostatically pressurizing the electrodeposition structure to a pressure above ambient pressure; cooling the electrodeposition structure to ambient temperature; and depressurizing the electrodeposition structure to ambient pressure.

Abstract: A method for treating alloy before and after friction stir welding, the method comprising the following steps. First solution heat treating a multiplicity of aluminum-zinc alloy engineered components for a first time period at a first temperature. First air cooling the components in ambient air at room temperature until the components are cooled to room temperature. Friction stir welding the components to form an assembly. Second solution heat treating the assembly for a second time period at a second temperature. Additional steps and embodiments are considered.

Abstract: A steel composition, in which, Si content is regulated to a given range and Nb and Cu or Ni, Mo are compositively added, and a recrystallization annealing is carried out to form an internal oxide layer just beneath a surface of a steel sheet and a surface oxide simultaneously formed on the surface of the steel sheet is removed by pickling. As a result, the formation of oxides of Si, Mn and the like is considerably decreased on the surface of the steel sheet in a subsequent heating before plating because the above internal oxide layer acts as a diffusion barrier. Thus, there can be obtained high tensile strength hot-dipped steel sheets having a considerably excellent plating property.

Abstract: A method of coating a pre-formed trainable material, such as nitinol wire, with a heat resistant substance, heat treating, and cooling to form a desired shape. The substance can be removed by various methods after heat treatment, depending upon the composition of the substance. The method includes forming a trainable material around a mold that dissolves, vaporizes, or can otherwise be removed. The method is useful for forming complicated shapes that would be expensive or impossible to form by conventional methods.

Abstract: A method for fabricating devices in a pre-assembled state comprising forming plural laminae, registering the laminae, and bonding the laminae one to another is described. The plural laminae contain the substructures and structures of the device. The substructures are coupled to structures and other substructures by fixture bridges in the pre-assembled state. The substructures of the device are dissociated by eliminating the fixture bridges. The plural laminae are registered and bonded to form the device either before or after the fixture bridges are eliminated. The fixture bridges can be eliminated in a variety of ways, including vaporization by electrical current, chemical dissolution, or thermochemical dissociation. One method to selectively bond the laminae together is by microprojection welding. Microprojection welding comprises forming laminae with projections that extend from at least one planar surface of the lamina.

Abstract: The present invention is directed to a metal block suitable for machining, the metal block comprising at least two superimposed metal plates, each having a thickness of at least 12.5 mm, wherein the yield strength of the block is at least 75% of the yield strength of the initial metal plate(s). The present invention is further directed to methods for manufacturing such blocks from two or more thick metal plates by explosive welding and other methods. Blocks according to the present invention are useful, for example, for manufacturing aircraft structural components or injection molds for plastics or rubber.

Abstract: A welded steel pipe is formed by heating or soaking an untreated welded steel pipe having a steel composition containing, on the basis of mass percent: about 0.03% to about 0.2% C, about 2.0% or less of Si, not less than about 1.0% to about 1.5% Mn, about 0.1% or less of P, about 0.01% or less of S, about 1.0% or less of Cr, about 0.1% or less of Al, about 0.1% or less of Nb, about 0.1% or less of Ti, about 0.1% or less of V, and about 0.01% or less of N; and by reduction-rolling the treated steel pipe at a cumulative reduction rate of at least about 35% and a final rolling temperature of about 500° C. to about 900° C. The welded steel pipe exhibits excellent hydroformability, i.e., has a tensile strength of at least about 590 MPa and an n×r product of at least about 0.22. The treated steel pipe is preferably reduction-rolled at a cumulative reduction rate of at least about 20% below the Ar3 transformation point.

Abstract: A method of preparing a biaxially textured article includes the steps of: rolling a metal preform while applying shear force thereto to form as-rolled biaxially textured substrate having an a rotated cube texture wherein a (100) cube face thereof is parallel to a surface of said substrate, and wherein a [100] direction thereof is at an angle of at least 30° relative to the rolling direction; and depositing onto the surface of the biaxially textured substrate at least one epitaxial layer of another material to form a biaxially textured article.

Abstract: A welded steel pipe is formed by heating or soaking an untreated welded steel pipe having a steel composition containing, on the basis of mass percent: about 0.05% to about 0.2% C; about 0.2% or less of Si; about 1.5% or less of Mn; about 0.1% or less of P; about 0.01% or less of S; about 0.1% or less of Al; and about 0.01% or less of N; and by reduction-rolling the treated steel pipe at a cumulative reduction rate of at least about 35% and a final rolling temperature of about 500° C. to about 900° C. The welded steel pipe exhibits excellent hydroformability, i.e., has a tensile strength of at least about 400 MPa and an n×r product of at least about 0.22. The treated steel pipe is preferably reduction-rolled at a cumulative reduction rate of at least about 20% below the Ar3 transformation point. The welded steel pipe is suitable for forming structural components.

Abstract: A method of manufacturing a metallic film consisting of giant single crystal grains is disclosed. The method includes depositing the metallic film on a substrate under an atmosphere of an inert gas and a specified additive gas to change a surface energy, grain boundary energy, or internal strain energy of the metallic film. The method also includes annealing step of the resultant of the deposition at a temperature suitable for the grain growth of the metallic film containing the additive gases. According to the method, the metallic film consisting of giant single crystal grains having a grain size whose ratio of thickness to an average grain size of the film is above 50 can be produced without depending upon the kind of substrate and deposition method.

Abstract: A group of alloys suitable for use in a high-temperature, oxidative environment, a protective coating system comprising a diffusion barrier that comprises an alloy selected from the group, an article comprising the diffusion barrier layer, and a method for protecting an article from a high-temperature oxidative environment comprising disposing the diffusion barrier layer onto a substrate are presented.

Abstract: A method and structure for forming a refractory metal liner, includes depositing a layer of refractory metal on a first conductive layer, at least half of the depositing being carried out in the presence of an amount of passivating agent that is sufficient to impede subsequent reaction of at least a top half of the layer of refractory metal with the first conductive layer and is less than an amount of passivating agent necessary to form a stoichiometric refractory metal with the passivating agent, and annealing the refractory metal and the first conductive layer in a first element ambient, thereby forming a stoichiometric refractory metal with the first element in at least a portion of the top half of the layer of refractory metal.

Abstract: The present invention provides a grain-oriented silicon steel sheet excellent in adhesiveness to tension-creating insulating coating films formed on the grain-oriented silicon steel sheet produced by removing inorganic mineral films composed of forsterite and so on with pickling or the like or by deliberately preventing the formation thereof, characterized by: having, at the interface between each of the tension-creating insulating coating films and the steel sheet, an external oxidation type membranous oxide film of 2 to 500 nm in average thickness mainly composed of amorphous silica and/or a mixed oxide film consisting of an external oxidation type membranous oxide film of 2 to 500 nm in average thickness mainly composed of amorphous silica and particulate oxides mainly composed of amorphous silica: and satisfying any one or more of the specified requirements.

Abstract: A weld filler metal alloy composition and a method for welding stainless steel components into a final assembly includes the steps of: austenitizing the stainless steel components to be welded at a temperature of 1800° F.-2000° F.; applying, using conventional arc welding techniques a solid wire of the filler metal alloy comprising in % by weight: up to 0.02% carbon; up to 0.8% manganese; up to 0.02% phosphorus; up to 0.015% sulfur; up to 0.6% silicon; 4.5-5.5% nickel; 0.4-0.7% molybdenum; 10-12.5% chromium; up to 0.1% copper; balance essentially iron and incidental impurities; and tempering the welded assembly welded at a temperature of 930° F.-1300° F. A second tempering step conducted at a temperature of 1095° F.-1145° F. may follow. The welding method can be used to make compressor impellers (6). The compressor impeller components comprise 13Cr-4Ni stainless steel.

Abstract: The invention provides a galvannealed steel sheet which has an oxide layer having 10 nm or larger thickness on the plateau of the coating layer flattened by temper rolling. With the use of the galvannealed steel sheet, no powdering occurs during press-forming, and stable and excellent sliding performance is attained. By selecting the area percentage of the plateau of the flattened coating layer to a range from 20 to 80%, making the coating layer single layer of &dgr;1 phase, and letting &zgr; phase exist in the &dgr;1 phase, further improved sliding performance and anti-powdering property are obtained.

Abstract: The present invention is directed to a method and apparatus for simultaneously cleaning and annealing a plated semiconductor workpiece. A chamber for simultaneously cleaning and annealing a semiconductor workpiece is provided herein. The method according to the present invention includes the steps rinsing the workpiece with mineral acids and DI water, then simultaneously cleaning/annealing the workpiece with heated deoxygenated DI water. By this present method, tool cross contamination by way of plated metal is greatly reduced, and also grain recovery and grain growth at room temperature is greatly accelerated. Thus, the annealing time of grain growth is dramatically reduced using the present method and apparatus.

Abstract: A welded steel pipe is formed by heating or soaking an untreated welded steel pipe having a steel composition comprising, on the basis of mass percent: about 0.05% to about 0.3% C; about 2.0% or less of Si; more than about 1.5% to about 5.0% Mn; about 0.1% or less of P; about 0.01% or less of S; about 0.1% or less of Cr; about 0.1% or less of Al; about 0.1% or less of Nb; about 0.3% or less of Ti; and about 0.01% or less of N; and by diameter-reduction-rolling the treated steel pipe at a accumulated diameter reduction rate of at least about 35% and a finish rolling temperature of about 500° C. to about 900° C. The welded steel pipe exhibits excellent hydroformability, i.e., has a tensile strength of about 780 MPa or more and a n×r product of at least about 0.15. The treated steel pipe is preferably diameter-reduction-rolled at a accumulated diameter reduction rate of at least about 20% below the Ar3 transformation point.