Abstract: Steel for induction hardening wherein coarsening of austenite crystal grains can be prevented even at a high temperature of over 1100° C. such as which occurs at projecting parts of steel parts at the time of induction hardening, the steel for induction hardening characterized by containing, by mass %, C: 0.35 to 0.6%, Si: 0.01 to 1%, Mn: 0.2 to 1.8%, S: 0.001 to 0.15%, Al: 0.001 to 1%, Ti: 0.05 to 0.2%, and Nb: 0.001 to 0.04%, restricting N: 0.0060% or less, P: 0.025% or less, and O: 0.0025% or less, satisfying Nb/Ti?0.015, and having a balance of iron and unavoidable impurities.

Abstract: A method for enhancing the formability of press-formed high strength, age-hardenable aluminum alloy sheet is disclosed. The sheet is partially formed when in an overaged condition, for example in a T7 or T8 temper condition, to form a preform. After an annealing and solutionizing process the preform is promptly further deformed in a second forming operation and subsequently aged to develop high strength. The method may be employed to form components of more complex shape from higher strength aluminum alloys such as 6000 series and 7000 series alloys.

Abstract: According to one embodiment, a high-strength stabilizer steel for vehicles having excellent corrosion resistance and low-temperature toughness, containing 0.07 to 0.20% C, more than 0.6% and 1.5% or less Si, 1 to 3% Mn, 0.1 to 1.0% Cr, 0.005 to 0.080% sAl, 0.005 to 0.060% Ti, 0.005 to 0.060% Nb, 0.070% or less Ti+Nb, 150 ppm or less N, 0.035% or less P, 0.035% or less S, 0.01 to 1.00% Cu, 0.01 to 1.00% Ni, the remainder being Fe, and unavoidable impurities, wherein a structure before molding a stabilizer is any one of a bainite, a martensite, and a mixed structure of bainite/martensite and an original austenitic crystal grain size number after a heat treatment of the stabilizer is Gh 9 or more.

Abstract: A roller bearing element for a large roller bearing includes the following features: at least one contact zone for a roller bearing counter element, the contact zone has an induction-hardened surface layer, the roller bearing element is comprised of a steel, which includes an admixture of carbon of at least 0.46 mass %.

Abstract: A high-strength die-quenched part 1 is formed by heating a high-strength steel sheet 11 up to an austenite region, hot stamping and cooling inside a mold, and its microstructure has the martensite wherein carbide particles 2 are finely dispersed over an entire region including prior-austenite grain boundaries. It is desirable that the prior-austenite grain size in the microstructure of the high-strength steel sheet, which is a base material, be 10 ?m or smaller. The high-strength die-quenched part has high-strength and high-ductility thanks to its martensite.

Abstract: A high strength steel plate containing 0.02 to 0.08% C, by mass, and has substantially a two phase microstructure of ferrite and bainite. The ferrite contains precipitates having a particle size of 30 nm or smaller grain size. The steel plate has a yield strength of 448 MPa or higher. A method for manufacturing the high strength steel plate which comprises hot rolling, accelerated cooling and reheating. The accelerated cooling is conducted down to a temperature of 300 to 600° C. at a cooling rate of 5° C./s or higher. The reheating is conducted up to a temperature of 550 to 700° C. at a heating rate of 0.5° C./s or higher.

Abstract: A holder having a baseplate with a tang extending rearwardly therefrom, a plurality of openings for receiving fasteners and a plurality of legs extending from the baseplate, the tang being heat treated or work hardened to harden the tang and facilitate its detachment for non-friable substrate applications. Work hardening may be accomplished, for example, by heating and quenching the tang to increase both its hardness and its brittleness to a level that allows the tang to be broken off with an impact force but not when inserted into a friable substrate so that the holder retains greater functionality.

Abstract: A method of forming a product from an initial blank comprises subjecting the initial blank to a hot forming and press hardening operation to form the product with substantially a uniform first tensile strength. Subsequently, the product is subjected to post hot-forming processing in which a first region of the product is heated selectively to above a known temperature, using one of conduction heating, resistance heating, and induction heating. The first region is then cooled, such that the first region attains a second tensile strength that is substantially less than the first tensile strength.

Abstract: An apparatus for the heat-treating of a heat-hardenable steel cruciform article having a weld seam includes a heating element to heat the weld seam to a point that an austenitic transformation occurs, and a quenching chamber to cool the weld seam, causing the formation of Martensite and an associated expansion. The quenching is rapid since slow quenching may allow a crystalline phase other than martensite to form. The apparatus may comprise rollers operable to convey the welded cruciform article through the apparatus at a speed such that the weld seam is subjected to heating for a predetermined heat time sufficient to cause a formation of martensite there within, and such that the heated portion reaches the quenching chamber and is quenched to create a substantial amount of martensite, e.g., an amount sufficient to cause expansion of the part.

Abstract: According to one embodiment, a high-strength stabilizer steel for vehicles having excellent corrosion resistance and low-temperature toughness, containing 0.07 to 0.20% C, more than 0.6% and 1.5% or less Si, 1 to 3% Mn, 0.1 to 1.0% Cr, 0.005 to 0.080% sAl, 0.005 to 0.060% Ti, 0.005 to 0.060% Nb, 0.070% or less Ti+Nb, 150 ppm or less N, 0.035% or less P, 0.035% or less S, 0.01 to 1.00% Cu, 0.01 to 1.00% Ni, the remainder being Fe, and unavoidable impurities, wherein a structure before molding a stabilizer is any one of a bainite, a martensite, and a mixed structure of bainite/martensite and an original austenitic crystal grain size number after a heat treatment of the stabilizer is Gh 9 or more.

Abstract: A method of thermal forming of refractory alloy suture needles is disclosed. Needle blanks made from refractory alloys are used to form surgical needles, which are heated to a temperature above the ductile to brittle transition temperature but below the recrystallization temperature of the refractory alloy. The heated needle blanks are then mechanically formed into a surgical needle. A Fixture and an apparatus for forming refractory alloy surgical needles using this method are also disclosed.

Abstract: A high-strength steel pipe having a strength of API X65 grade or higher consisting essentially of, by mass %, 0.02 to 0.08% of C, 0.01 to 0.5% of Si, 0.5 to 1.8% of Mn, 0.01% or less of P, 0.002% or less of S, 0.01 to 0.7% of Al, 0.005 to 0.04% of Ti, 0.05 to 0.50% Mo, at least one element selected from 0.005 to 0.05% of Nb and 0.005 to 0.10% of V, and the balance being Fe, in which the volume percentage of the ferritic phase is 90% or higher, and complex carbides containing Ti, Mo, and at least one element selected from the group consisting of Nb and V are precipitated in the ferritic phase. The high-strength steel pipe has excellent HIC resistance and good toughness of a heat-affected zone, and can be manufactured stably at a low cost.

Abstract: A method for producing a structural and/or safety-related motor vehicle component having at least one hot-formed and press-hardened part constructed from high-strength steel includes the steps of partially heat-treating a region of the motor vehicle component by heating the region to a heat-up temperature in a temperature range between 500° C. and 900° C.; maintaining the heat-up temperature for a duration of a holding time; and cooling down from the heat-up temperature in one or more phases. A body component constructed as a structural and/or safety-related motor vehicle component from a steel sheet blank that has been hot-formed and press-hardened includes joining flanges and/or coupling locations and/or safety-related parts, wherein the joining flanges, coupling locations and/or safety-related parts are partially heat-treated in several steps with the disclosed method.

Abstract: To produce a metallic shaped part (1), in particular a vehicle body part, from a semifinished product (2) made of an unhardened hot-workable steel sheet, first of all the semifinished product (2) is formed by a cold-forming method, in particular a drawing method, into a part blank (10) (process step II). The part blank (10) is then trimmed at the margins to a marginal contour (12?) approximately corresponding to the part (1) to be produced (process step III). Finally, the trimmed part blank (17) is heated and press-hardened in a hot-forming tool (23) (process step IV). The part (1) produced in the process already has the desired marginal contour (24) after the hot forming, so that the final trimming of the part margin is dispensed with. In this way, the cycle times during the production of hardened parts of steel sheet can be considerably reduced.

Abstract: According to one aspect of the present invention, there is provided a process of fabricating a steel material by performing a heat treatment to a steel material having high strength, in order to reduce hardness at one part of the steel material to less than hardness at other parts of the steel material, wherein the heat treatment comprises a heating step in which a portion having a certain depth from a surface of the steel material is rapidly heated by induction heating or direct energization heating, and a cooling step in which the steel material, which has been subject to the heating step, is rapidly cooled a predetermined time after the heating step, and a heating temperature in the heating step is Ac1 transforming point or more.

Abstract: The invention relates to a method for producing hardened profiles, in particular hardened open profiles, wherein the component is at least partly heated to above the austenitizing temperature of the base material and after heating the component is cooled at a rate above the critical hardening rate, the energy necessary for the heating being introduced at least partly by induction, wherein free edges are provided in the component to adjust a temperature or hardness gradient over the cross section of the component, the size, type and extension of the edges being set for a desired degree of hardness and/or hardness gradient.

Abstract: A device for removing layers of corrosion and other coatings from a metal surface is disclosed. Said device includes a signal generator driving an induction coil that is positioned on the structure. A control unit includes a temperature sensor that senses the temperature in the metal structure. The control unit is adapted to control the power output of the signal generator in accordance with the temperature in the metal structure.

Abstract: The present invention provides a method of manufacturing a steel product, comprising the step of heat treating a steel product having been subjected to quenching or accelerated cooling on a hot rolling line after hot rolling to pass the steel product through a plurality of induction heating apparatuses, which are installed on the hot rolling line, three times or more. The method of the present invention makes it possible to uniformly heat treat the steel product with high productivity.

Abstract: A bearing component formed from a bearing steel, wherein the component has an outer surface and comprises through-hardened bainite and/or martensite and has a substantially homogeneous chemical composition, at least a part of the bearing component having a compressive residual stress profile comprising ?25 to ?1000 MPa at the near surface, wherein the near surface is defined as a region 500 microns or less below the outer surface.

Abstract: The invention discloses a soft magnetic amorphous alloy and a soft magnetic nanocomposite alloy formed from the amorphous alloy. Both alloys comprise a composition expressed by the following formula: (Fe1-x-yCoxMy)100-a-b-cTaBbNc where, M is at least one element selected from the group consisting of Ni and Mn; T is at least one element selected from the group consisting of Nb, W, Ta, Zr, Hf, Ti, Cr, Cu, Mo, V and combinations thereof, and the content of Cu when present is less than or equal to 2 atomic %; N is at least one element selected from the group consisting of Si, Ge, C, P and Al; and 0.01?x+y<0.5; Q?y?0.4; 1<a<5 atomic %; 10<b<30 atomic %; and 0<c<10 atomic %. A core, which may be used in transformers and wire coils, is made by charging a furnace with elements necessary to form the amorphous alloy, rapidly quenching the alloy, forming a core from the alloy; and heating the core in the presence of a magnetic field to form the nanocomposite alloy.

Abstract: A method for tempering a workpiece is provided. The method includes providing a ferrous alloy workpiece having a martensite and/or bainite phase therein, heating at least a portion of the workpiece to a preselected temperature and then cooling the workpiece to a lower temperature. The preselected temperature is below the austensizing temperature of the alloy and the heating is accomplished in no more than 60 seconds. One embodiment of the present invention heats the workpiece using resistance heating.

Abstract: A method for annealing a strip of steel having a variable thickness in its length direction with at least thicker and thinner sections, wherein the strip has been cold rolled to form the thicker and thinner sections, one thicker and one thinner section having a length of at most a few meter. The annealing is performed by continuous annealing.

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 (S1) and a tempering step (S2) being carried out after the quench-hardening step (S1), the quench-hardening step (S1) includes a first quench-hardening step (S11) and a second quench-hardening step (S12) being carried out after the first quench-hardening step (S11), the entire region of the columnar work (3) from an outer circumferential surface (31f) to a core thereof (32), 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: A hot rolled dual phase steel strip with Thickness® 1.0 mm can be used for producing cold pressed and cut pieces, in particular for the car manufacturing industry, by replacing with the same mechanical performances the cold rolled dual phase steel strip usually employed for these purposes. Said hot rolled strip in peritectic steel has a carbon percentage between 0.06 and 0.15% with chemical analysis without any important addition of chromium and phosphorous, with a constant geometrical profile on the whole length and tolerances, particularly with respect to the thickness, which are typical of a cold rolled strip with parallelism <0.05 mm, crown between strips centre and side edges <0.07 mm, while showing a structure with a microcrystalline fineness better than grade 10 of the ASTM 112 standard in a percentage higher than 80% of the whole structure.

Abstract: The invention relates to a high-hardness palladium alloy for manufacturing semi-finished products to be used in goldsmith's art or jewels to be obtained by the lost wax casting method, which comprises, in the following concentrations, expressed in thousandths by weight (‰): palladium from 948 to 990‰; copper from 0.0 to 50‰; indium from 0.0 to 50‰; gallium from 1 to 48‰; aluminium from 0.8 to 49.5‰; ruthenium from 0.0 to 50‰; rhenium from 0.0 to 50‰; silicon from 0.1 to 1.2‰; platinum from 0.0 to 40‰; nickel from 0.0 to 50‰; iridium from 0.0 to 40‰. In the manufacturing process of the above alloy, the component elements of said alloy are placed in a crucible, respectively made of zirconia, boron nitride or other ceramic material, and are melted using the induction method and using a protective atmosphere, respectively of argon, nitrogen or other inert gas.

Abstract: A process for producing a profile component from a semi-finished sheet metal part, which at least in certain sections has a structurally increased strength. The semi-finished sheet metal part is formed in an at least a single-stage bending process. The bending process and also subsequent parting and cutting operations on the semi-finished sheet metal part are combined with a thermal treatment of at least one geometrically delineated region of the semi-finished sheet metal part. The thermal treatment comprises at least one heating step and is combined with a subsequent cooling step, in such a way that the at least one geometrically delineated region has a structurally increased strength after cooling. Bending can be effected by using roller profiling wherein rollers are preferably cooled or swage bending.

Abstract: A steel for use in high strength pinion shaft which is not refined and used by applying high frequency hardening, with less occurrence of peeling during hobbing, having high surface hardness, impact value and torsional strength after high frequency hardening, and with less heat treatment strains during high frequency hardening, containing, on the mass % basis; C: 0.45-0.55%, Si: 0.10-0.50%, Mn: 0.50-1.20%, P: 0.025% or less, S: 0.025% or less, Mo: 0.15-0.25%, B: 0.0005-0.005%, Ti: 0.005-0.10%, and N: 0.015% or less, satisfying: 0.80?Ceq 0.95 and f value?1.0, and the balance of Fe and inevitable impurities, as well as a manufacturing method thereof.

Abstract: A method for the treatment of sheets which are rolled to final dimensions in a roll stand, subsequently undergoing on-line cooling, straightening and heat treatment for homogenization and influencing of microstructure. To improve the heat treatment, the heat treatment is carried out online such that it is decoupled from the preceding cooling and straightening, while taking into account the speed at which the sheet exits from the final workstation upstream, the time at which the heat treatment begins is selected in such a way that the sheet has completely left this final workstation before the sheet is subjected to the heat treatment.

Abstract: The invention relates to the hardening of the surface layer of parts of machines, plants and apparatuses and also tools. Objects for which the application is possible and advantageous are components which are subjected to severe fatigue or wear stresses and are composed of hardenable steels and have a complicated shape and whose surface has to be hardened selectively on the functional surfaces or whose functional surface has a multidimensional shape. The process for hardening the surface layer of components having a complicated shape is carried out by means of a plurality of energy input zones.

Abstract: The invention relates to a method for producing strips (1) of steel, preferably of silicon steel, in particular of grain-oriented silicon steel or of multiphase steel in which a slab (3) is initially cast in a casting machine (2), wherein this is then rolled in at least one roll train (4, 5) to form strip (1) and wherein before and/or after the at least one roll train (4, 5), the slab is heated in at least one furnace (6, 7).

Abstract: A continuous annealing facility comprised of a heating zone, soaking zone, and cooling zone is used for continuous annealing of a steel strip having a Curie point (Tc) by an annealing temperature over Tc during which the heat treatment in the heating zone is divided into three regions, in a first heating zone, a radiant heating means using gas heating and/or a radiant heating means using electric heaters is used to heat the steel strip to less than Tc?50° C., in a next second heating zone, the heated steel strip is heated by a solenoid coil type high frequency induction heating means to a region of Tc?30° C. to Tc?5° C., and, in a final third heating zone, the heated steel strip is heated by a radiant heating means using gas heating and/or a radiant heating means using electric heaters to a treatment target temperature over Tc to thereby anneal a steel strip having a Curie point uniformly in the longitudinal direction.

Abstract: Various inexpensive rolling elements for use under high interface pressure such as induction hardened gears are provided, which have improved seizure resistance at tooth flanks and a temper hardness of HRC 50 or more at 300 ° C. To this end, a rolling element is made from a steel material which contains at least 0.5 to 1.5 wt % carbon and 0.2 to 2.0 wt % one or more alloy elements selected from V, Ti, Zr, Nb, Ta and Hf; and in which 0.4 to 4.0% by volume one or more compounds selected from the carbides, nitrides and carbonitrides of the above alloy elements and having an average particle diameter of 0.2 to 5 ?m are dispersed. In such a rolling element, the soluble carbon concentration of a martensite parent phase of a rolling contact surface layer is adjusted to 0.3 to 0.8 wt %, the martensite parent phase having been subjected to induction hardening and low temperature tempering, and one or more of the above carbides, nitrides and carbonitrides are dispersed in an amount of 0.4 to 4.

Abstract: We provide a steel product that includes, by mass %, C: 0.35-0.7%, Si: 0.30-1.1%, Mn: 0.2-2.0%, Al: 0.005-0.25%, Ti: 0.005-0.1%, Mo: 0.05-0.6%, B: 0.0003-0.006%, S: 0.06% or less, P: 0.02% or less, Cr: 0.2% or less, and the balance Fe and inevitable impurities, and has a structure of bainite and/or martensite, the total volume fraction of bainite and martensite being 10% or more, and an induction hardened member that is made of the steel product having a hardened surface layer formed by induction hardening and has a prior austenite grain size of 12 ?m or less through the layer thickness. The member has high fatigue strength and therefore is suitable for an automobile drive shaft, an automobile constant velocity joint or the like.

Abstract: A heat treatment apparatus 10 comprises a supporting unit 20 for supporting a columnar workpiece 12 turnably, and an induction-heating coil 30 for induction-heating the workpiece 12 supported turnably by the supporting unit 20. Below the workpiece 12 supported by the supporting unit 20, a cooling tank 50 is provided which contains a liquid coolant. The workpiece 12 is made of steel such as carbon steel for mechanical structure, and spring steel. The workpiece 12 is made of a material which has a magnetic transformation point at 770° C. The material is ferromagnetic below this temperature, and becomes paramagnetic above this temperature.

Abstract: A method of protecting an element from excessive surface wear is provided. In this method, a localized area of the element that will be subjected to excessive surface wear is exposed to induction heating for a period sufficient to heat the localized area to an elevated temperature at which the localized area undergoes austenitic transformation. The localized area is quenched, followed by tempering, and then cooling. A result of the method is a localized hardened area formed monolithically with the element and having a localized hardness that is greater than a base hardness of the element.

Abstract: Quenched layers are formed without irregularities on the inner circumferential surface of a track bushing having a small inside diameter or on the inner circumferential surfaces of two or more track bushings which are subjected to quenching in an overlapped condition. To introduce a cooling medium for cooling the inner circumferential surface of the track bushing, a guide tube having an outside diameter smaller than the inside diameter of the track bushing is disposed on the side of the inner circumferential surface and the cooling medium introduced by the guide tube is diverted by a diverting member having a spherical or similar curved surface, such that the cooling medium is allowed to flow in a direction substantially parallel with an axial direction of the track bushing 1 within a space defined by the outer circumferential surface of the guide tube and the inner circumferential surface of the track bushing, thereby performing laminar flow cooling.

Abstract: Improved induction coil apparatus and methods are presented for induction hardening undercut fillets of crankshafts or other workpiece recesses in which an active turn is energized for heating a journal area in the workpiece recess and one or more passive turns are translated toward undercut fillets once the coil assembly is moved toward the recess with coupling portions of the passive and active turns coupling energy from the active turn to the passive turn(s) for heating the undercut fillets.

Abstract: Method for increasing the fatigue strength of a mechanical part of a wind turbine and/or for reducing the tendency to form what are called “white etching cracks” or “brittle flakes” in such a bearing, which includes making one or several of the bearing rings and/or roller elements concerned of the bearing at least partly of a hardened steel having a carbon content between 0.4 and 0.8 percent by weight.

Abstract: A method for producing hot-rolled strip from austenitic stainless steels. In a first step, a cast product is subjected to a rolling operation in a rolling mill with a finishing train, and, in a second step, a heat treatment is carried out to prevent susceptibility to corrosion, especially intergranular corrosion due to chromium carbide precipitation. To establish the final rolling temperature (Twe), a run-in temperature (Tein) of the cast product into the finishing train of the rolling mill that is above 1,150° C., and preferably above 1,200° C., is established by a multistage heating process, especially a two-stage heating process, which comprises a preheating stage and an intensive heating stage, and the heat treatment is carried out by directly utilizing the rolling heat.

Abstract: An induction heat treatment method with which temperature control is enabled, condition setting is easy, and the quality of a treatment object can be stabilized includes: a data acquiring step of heating and quench-hardening a sample of the treatment object to thereby acquire process data; a storing step of storing the process data; a checking step of checking the power supply output transition data and the quenching timing data as to validity based on the temperature transition data stored in the storing step; and a mass production step of performing heat treatment of the treatment object in accordance with the power supply output transition data and the quenching timing data stored in the storing step and checked as to validity in the checking step.

Abstract: A holder having a baseplate with a tang extending rearwardly therefrom, a plurality of openings for receiving fasteners and a plurality of legs extending from the baseplate, the tang being heat treated or work hardened to harden the tang and facilitate its detachment for non-friable substrate applications. Work hardening may be accomplished, for example, by heating and quenching the tang to increase both its hardness and its brittleness to a level that allows the tang to be broken off with an impact force but not when inserted into a friable substrate so that the holder retains greater functionality.

Abstract: An apparatus for the heat-treating of a heat-hardenable steel cruciform article having a weld seam includes a heating element to heat the weld seam to a point that an austenitic transformation occurs, and a quenching chamber to cool the weld seam, causing the formation of Martensite and an associated expansion. The quenching is rapid since slow quenching may allow a crystalline phase other than martensite to form. The apparatus may comprise rollers operable to convey the welded cruciform article through the apparatus at a speed such that the weld seam is subjected to heating for a predetermined heat time sufficient to cause a formation of martensite there within, and such that the heated portion reaches the quenching chamber and is quenched to create a substantial amount of martensite, e.g., an amount sufficient to cause expansion of the part.

Abstract: A simpler and less expensive method of fabricating pressed components from sheet steel that can be heat treated while inside the press, whereby the material is heated to above its transformation point Ac3, pressed, and cooled, controlled, to below its crystalline-transformation point. The sheet is unwound from a coil (1), heated to above its transformation point, pressed in a press, and separated.

Abstract: The present invention provides a leaf spring material superior in mechanical characteristics and a manufacturing method of the leaf spring material capable of reliably achieving the same, utilizing induction hardening. The manufacturing method of the leaf spring material comprises the steps of imparting tensile stress on a first surface along the longitudinal direction of the first surface and compressive stress on a second surface along the longitudinal direction of the second surface of a substantially strip-shaped steel plate, and subjecting the first surface to induction hardening. With this induction hardening, an induction-hardened structure having a higher average hardness than that of a parent material structure in the vicinity of the second surface and comprising martensite and finely and evenly dispersed austenite is imparted on a surface layer in the vicinity of the first surface.

Abstract: The present invention provides a leaf spring material superior in mechanical characteristics and a manufacturing method of the leaf spring material capable of reliably achieving the same, utilizing induction hardening. The leaf spring material comprises a substantially strip-shaped steel plate having a first surface and a second surface. The leaf spring material has in the vicinity of the first surface a hardened layer comprising an induction-hardened structure having a higher average hardness than that of the parent material structure in the vicinity of the second surface, and a compressive residual stress layer of a thickness at least not smaller than that of the thickness of the hardened layer in the vicinity of the first surface. Such a characteristic structure is achieved by stress-induced hardening that imparts a predetermined tensile stress or higher.

Abstract: In a method for heat treating a fuel assembly channel made of zircaloy, the channel is continuously moved relative to a heat-treatment device and, longitudinal sections of it are heated to the beta phase range in an inductive heating zone. The longitudinal section of the channel heated in this manner is than cooled in a cooling zone to a temperature within an alpha phase range. The heat treatment is effected by at least two heating devices, which are spaced apart from one another, operate independently of each other, and each contain at least one induction coil and together form a heating zone. The channel section is first heated using a first heating device and then heat-treated using a second heating device which has less power and in that cooling is effected using a stream of inert gas applied to the outer surface of the channel.

Abstract: Long work of Fe based alloy while being rotated at a given rotation speed under the action of rotating chucks is heated by high-frequency heating coil to thereby accomplish the heating step. In the first cooling step after termination of the heating, the long work while having its rotation speed increased is brought into contact with first to fourth correction rollers, and in that state is cooled so as to fall within a temperature range of Pf temperature or below to over Ms temperature. The time spent in the cooling preferably ranges from 5 to 10 sec. In the subsequent second cooling step, the rotation speed of the long work is reduced, preferably so as to be equal to that at the heating, and cooling of the long work is continued.

Abstract: A method of thermal forming of refractory alloy suture needles is disclosed. Needle blanks made from refractory alloys are used to form surgical needles, which are heated to a temperature above the ductile to brittle transition temperature but below the recrystallization temperature of the refractory alloy. The heated needle blanks are then mechanically formed into a surgical needle. A Fixture and an apparatus for forming refractory alloy surgical needles using this method are also disclosed.

Abstract: There is provided a component for machine structure having a hardened layer through an induction hardening in at least a part thereof, and more improving fatigue strengths as compared with the conventional ones, in which the hardened layer has a hardness Hv of not less than 750 and an average grain size of prior austenite grains is not more than 7 ?m over a full thickness of the hardened layer.

Abstract: There is provided an inexpensive rolling element used under high interface pressure such as induction hardened gears, the rolling element being improved in the seizure resistance of its tooth flanks and having a temper hardness of HRC 50 or more at 300° C. To this end, the rolling element is made from a steel material containing at least 0.45 to 1.5 wt % C and one or more alloy elements selected from 0.1 to 0.5 wt % V and 0.3 to 1.5 wt % Cr, and has a rolling contact surface layer having a structure tempered at low temperature in which 2 to 18% by volume cementite disperses in a martensite parent phase formed by induction heating and cooling and containing 0.25 to 0.8 wt % carbon solid-dissolving therein.