Abstract: A method for producing ultra-high strength martensitic cold-rolled steel sheet adopts pulsed ultra-rapid heating of cold-rolled martensitic steel sheets after smelting, solidification, hot rolling, billet or ingot casting, as well as conventional manufacturing processes such as hot continuous rolling and winding, pickling, and room temperature cold rolling. The steel sheets are rapidly heated at a heating rate of 100-500° C./s to a single-phase region of austenite, and then the samples are immediately water-cooled to obtain martensite structure without undergoing heat preservation or a very short holding time. The tensile strength of the martensitic steel is in the range of 1800-2300 MPa, and the total elongation can reach 12.3%. Compared with the continuous annealing product of the same martensitic steel, the tensile strength is increased by 700 MPa or more, and the maximum increase of total elongation is 6%.

Abstract: In a heat treatment method for obtaining a bearing ring for an annular roller bearing whose thickness changes in an axial direction, the heat treatment method includes (A) applying a quenching process to a work which is annular, made of high carbon chromium bearing steel, and having a thickness changing in an axial direction, (B) applying a tempering process to the work which is quenched to entirely soak the work in cooling liquid and inductively heat the work in a state that the work is soaked in the cooling liquid, and (C) applying a finishing process to the work which is tempered.

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: When a plurality of outer rings (R) are sequentially and inductively heated to a target temperature by energizing a heating coil (2) elongated more than each of the plurality of outer rings (R), which are made of steel and retained coaxially by a retaining unit (3), while relatively moving the outer rings (R) and the heating coil (2) in an axial direction, an output of the heating coil (2) is varied in consideration of the number of outer rings (R) present in an opposing region of the heating coil (2).

Abstract: A single shot inductor is provided to induction heat treat closely spaced multiple eccentric cylindrical components arranged along the longitudinal axis of a workpiece. The single shot inductor has multiple planar arcuate single turn coil sections separated from each other by an axial coil section so that each of the multiple planar arcuate single turn coil sections sequentially heat treats the closely spaced multiple eccentric cylindrical components inserted within the single shot inductor.

Abstract: A steel for an induction hardening including, by mass %, C: more than 0.75% to 1.20%, Si: 0.002 to 3.00%, Mn: 0.20 to 2.00%, S: 0.002 to 0.100%, Al: more than 0.050% to 3.00%, P: limited to 0.050% or less, N: limited to 0.0200% or less, O: limited to: 0.0030% or less, and the balance composing of iron and unavoidable impurities, wherein an Al content and a N content satisfy, by mass %, Al?(27/14)×N>0.050%.

Abstract: A method for forming and treating a steel article of a high strength and ductile alloy. The method includes the steps of providing a starting steel composition for the steel article, preheating the composition, heating the starting material to a peak temperature range in less than forty seconds, holding the heated steel composition at the peak temperature range for between two and sixty seconds, quenching the heated steel composition from the peak temperature range to below 177° C. (350° F.) at a temperature rate reduction of 200 to 3000° C./sec (360 and 5400° F./sec), removing residual quench media from the surface of the quenched steel composition, tempering the quenched steel composition at a temperature of 100 to 704° C. (212 to 1300° F.); and air cooling the tempered steel composition to less than 100° C. (212° F.) to form a steel having desired mechanical properties.

Abstract: Leaf springs, and methods of manufacturing thereof, having first and second sections, spaced apart along the length of said leaf spring, said sections are through hardened and tempered to achieve, respectively different levels of finished through hardness, are disclosed.

Abstract: The invention relates to a method for producing a component from transformable steel by hot forming, in which a plate first is cut out of a strip or sheet as the pre-material, and is then heated to forming temperature and pre-formed, having an at least partially martensitic transformation structure after forming. Instead of a press mould hardening, the at least partially martensitic transformation structure is created in the pre-material, or in the plate to be formed, by austenitisation and quenching already before forming, and then the thus-conditioned plate is reheated after forming, while maintaining the at least partially martensitic transformation structure, to a temperature below the Ac1 transformation temperature, and formed at this temperature.

Abstract: A non-scaling heat-treatable steel with particular suitability for producing hardened or die-hardened components is disclosed, characterized by the following chemical composition in % by weight: C 0.04-0.50; Mn 0.5-6.0; Al 0.5-3.0; Si 0.05-3.0; Cr 0.05-3.0; Ni less than 3.0; Cu less than 3.0; Ti 0.010-?0.050; B 0.0015-?0.0040; P less than 0.10; S less than 0.05; N less than 0.020; remainder iron and unavoidable impurities. Further disclosed is a method for producing a non-scaling hardened component from the steel and a method for producing a hot strip from a steel.

Abstract: A steel pipe with a wall thickness over 30 mm is subjected to heat treatment of quenching and tempering using a temperature range of at least not less than 750° C. during the heating stage, makes it possible to obtain a heavy-wall seamless steel pipe having excellent toughness by resulting grain refinement. Quenching is by performing water cooling after heating the steel pipe to a temperature in the range of not less than 900° C. to not more than 1000° C. by using, as a heating means, induction heating at a frequency of not more than 200 Hz. Tempering is performed at a temperature in the range of not less than 500° C. to not more than 750° C. Preferably, after the heating by induction heating, a soaking treatment is performed in the temperature range of not less than 900° C. to not more than 1000° C. for 10 minutes or less followed by water cooling.

Abstract: A method of producing a forged steel part is disclosed to include providing a steel billet having a composition including 0.25-0.40 wt. % C, 1.50-3.00 wt. % Mn, 0.30-2.00 wt. % Si, 0.00-0.150 wt. % V, 0.02-0.06 wt. % Ti, 0.010-0.04 wt. % S, 0.0050-0.0150 wt. % N, 0.00-1.00 wt. % Cr, 0.00-0.30 wt. % Mo, 0.00-0.003 wt. % B, and a balance of Fe and incidental impurities. The method may further include heating the steel billet to an austenization temperature of approximately 1150 degrees C. to 1350 degrees C., hot forging the steel billet to form the steel part, and controlled air cooling the forged steel part after the hot forging. The method may still further include induction heating select portions of the forged steel part after the controlled air cooling to increase the hardness of the select portions of the forged steel part, followed by quenching and tempering before the final machining.

Abstract: A method for forming and treating a steel article of a high strength and high ductility alloy particularly suited for use as armor plate. The method includes the steps of providing a starting material for the steel article, heating the starting material to a peak temperature range in less than ten seconds, holding the heated steel composition at the peak temperature range for between two and six seconds, quenching the heated steel composition from the peak temperature range to below 100° C. (212° F.) at a temperature rate reduction of 400 and 3000° C./sec (752 and 5432° F./sec), removing residual quench media from the surface of the quenched steel composition, tempering the quenched steel composition at a temperature of 100 to 260° C. (212 to 500° F.); and air cooling the tempered steel composition to less than 100° C. (212° F.) to form a steel having desired mechanical properties.

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: A method for forming and treating a steel article of a high strength and high ductility alloy particularly suited for use as armor plate. The method includes the steps of providing a starting material for the steel article, heating the starting material to a peak temperature range in less than ten seconds, holding the heated steel composition at the peak temperature range for between two and six seconds, quenching the heated steel composition from the peak temperature range to below 100° C. (212° F.) at a temperature rate reduction of 400 and 3000° C./sec (752 and 5432° F./sec), removing residual quench media from the surface of the quenched steel composition, tempering the quenched steel composition at a temperature of 100 to 260° C. (212 to 500° F.); and air cooling the tempered steel composition to less than 100° C. (212° F.) to form a steel having desired mechanical properties.

Abstract: A shaft part is formed with a rolling groove (5) on which rolling elements (4) roll. At least the rolling groove (5) is induction hardened with no generation of black colored oxidized scale after the induction hardening. A surface of the induction hardened rolling groove (5) is used “as is” as a rolling surface. The surface roughness Ra of the induction hardened surface “as is” of the rolling groove (5) is less than 1.0. The ratio of effective hardened depth of a hardened layer is between 0.15 and 0.45.

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: 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 method for heat treatment of a coiled spring includes cold forming a coiled spring, annealing the coiled spring after the cold forming, thereby removing of residual stress generated in the cold forming, in which the annealing is performed by electric resistance heating.

Abstract: The invention relates to a process for the continuous heat treatment of steel strip material whose thickness d1, d2 periodically varies along its length, more particularly of strip flexibly rolled with a roll gap varying as a function of time, wherein the continuous heat treatment of the strip material takes place while the strip material passes through an induction furnace in which the strip material is induction heated at a constant frequency which can be selected to be such that the mathematical induction depth ? of the induced current up to which the magnetic field has been reduced to 63% of the field strength of the outer field is greater than half the thickness of the strip portions with the smallest thickness d2.

Abstract: To provide a technique suitable for elevating strength and toughness of a thin low-carbon steel. By performing rapid heating and rapid cooling to a thin low-carbon steel which is an ordinary steel with a thickness of 1.2 mm or less, a steel where a microstructure becomes a duplex grain size structure mixed with crystal grains having different grain diameters, which is not homogeneous, preferably, hard phase structures are contained in addition to the duplex grain size structure is obtained, and a high-strength and high-toughness thin low-carbon steel is obtained. Further, by performing a heat treatment process involving rapid heating and rapid cooling multiple times, a duplex grain size structure of crystal grains with smaller grain diameters or a hard phase structure contained therein is obtained, so that a thin low-carbon steel with higher strength and higher toughness is obtained.

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 process for inducing a compressive residual stress in a surface region of a steel component, the process comprising a heat treatment having the following steps: (i) providing a component comprising a steel composition; (ii) induction heating at least a part of the component followed by quenching said at least part, wherein the hardness in a surface region of the component is increased; and (iii) subsequently performing a martensite and/or bainite through hardening step to obtain a microstructure comprising martensite and/or bainite.

Abstract: The subject of the invention is a process for the continuous manufacture of an austenitic stainless steel strip having a dull surface appearance, consisting in subjecting an austenitic stainless steel strip to a heat treatment in a bright annealing furnace inside which an inert or reducing flushing gas circulates, which gas has a dew point above ?15° C., and then in pickling the strip using a suitable acid pickling solution.

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 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: 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: 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 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: 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.

Abstract: A process that combines tubular body pressure induced shaping at elevated temperatures with a controlled rapid quenching operation using a gaseous quenching medium in a common unit. The achievable cooling rate permits the in-die shaping and quenching of tubular structural components of martensitic steels without requiring the use of a separate discrete quenching.

Abstract: An induction brazing and quenching apparatus and related method of coupling components together.

Abstract: The present invention provides a power transmission shaft that is capable of eliminating the usual tempering step thereby reducing the production cost, is capable of realizing an inline production process of the shaft, and has higher strength. The invention also provides a method for producing the power transmission shaft. The power transmission shaft is composed of a carbon steel having a carbon content of from 0.30 to 0.48 wt % and of a surface hardened layer 4 formed by high frequency quenching. The surface hardened layer 4 has a tempering-effected portion subjected to tempering using heat generated by external force applied after quenching. The residual stress of the portion subjected to tempering by applying external force is equal to or less than ?800 MPa.

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: A method for making a low carbon and low manganese cold rolled steel strip for deep-drawing whereby a steel strip hot rolled in the austenistic region coiled at the end of the high temperature hot rolling process (680° C.<T<750° C.) is subjected to a cold rolling process with a reduction rate between 65 and 80 %, and finally subjected to an annealing and overageing heat treatment. The method consists in heating the steel strip at a heating rate Vh ranging between 150° C./s and 1000° C. up to the annealing temperature Ta ranging between 650° C. and 750° C., and in maintaining it at said annealing temperature for a time interval between 1 and 20 seconds, then in cooling it at cooling rate Vc between 100° C./s and 500° C./s up to an overageing temperature Toa ranging between 150° C. and 450° C.

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 vehicle structural beam, such as a door intrusion beam, which possesses an elongate tubular beam part which at opposite ends is provided with mounting flanges for securement to a vehicle frame. The elongate tubular beam part and the flanges provided at opposite ends are defined by an integral, one-piece, monolithic steel structure which has been initially roll-formed from an elongate flat metal sheet to define the closed tubular structure of the tubular beam part, and which has been subjected to heating and quenching so that the elongate tubular beam part is of relatively high strength steel throughout its entire length, whereas the integrally and monolithically joined end flanges remain as lower strength steel which has been significantly unaffected by the heat treatment and quenching so as to permit appropriate shaping thereof and ease of welding to the vehicle frame.

Abstract: A method of hardening a work piece having (i) an outer surface, (ii) an inner surface which defines a passageway extending through the work piece, and (iii) an end. The method includes the steps of (A) advancing the work piece through a first induction coil such that a first hardened area is formed on the work piece, (B) advancing a second induction coil into the passageway of the work piece such that a second hardened area is formed on the work piece, and (C) positioning a third induction coil adjacent to the end of the work piece such that a third hardened area is formed on the work piece. The positioning the third induction coil step is performed after (i) the advancing the work piece through the first induction coil step and (ii) the advancing a second induction coil into the passageway step.

Abstract: Crawler belt bushings and heir producing methods, with which productivity and cost performance can be improved over the carburization treatment and the induction hardening treatment. After a workpiece made from steel is heated from its outer circumferential surface such that at least the surface temperature of the inner circumferential surface of the workpiece is raised to a quenching temperature, a series of quenching operation is performed to form quench hardened layers which extend toward the core from the inner and outer circumferential surfaces respectively and a soft, imperfectly hardened layer between these quench hardened layers. The quenching operation comprises: cooling the workpiece from the inner circumferential surface; cooling the workpiece from the inner circumferential surface while heating from the outer circumferential surface; and cooling the workpiece from the outer circumferential surface.

Abstract: A method and apparatus disclosed for cost-effective net shape precision ausform finishing the engagement surfaces of ball and roller bearings, for enhancing the surface strength and durability of bearing inner and outer races. The method consists of induction heating to austenitize the contacting surface layers of rolling element bearing races, followed by martempering (or marquenching), and then net shape roll finishing of the induction heated contacting surface layers in the metastable austenitic condition to finished dimensional accuracy requirements, and finally cooling to martensite. The apparatus utilizes a fixed vertical through-feed axis for the workpiece bearing race with capability for rotation and linear up and down positioning motion, and two coordinated and controlled laterally-moving infeed axes for roll finishing tooling dies.

Abstract: Conventional methods for heat treating cylindrical components such as track bushings involve multiple steps. For example, many such methods consist of carburizing, cooling, induction-hardening, quenching, and tempering. The conventional methods have proved to be costly because different heat treating apparatus are required. This causes duplicate handling and wasted manufacturing time. The present invention provides a method and apparatus 30 for heat treating a bushing 10 simultaneously from an outer peripheral surface and the pair of inner circumferential surfaces.

Abstract: A specialized induction facility provides localized heating in only the desired wear areas of a crane wheel while leaving the supporting material "as-forged" and ductile. The wear area of a crane wheel is hardened such that flanges extending out from a working tread surface are not completely through hardened.

Abstract: A grinding rod having a hardened outer shell of tempered martensite is adapted for use in heavy duty grinding environments. The rod is stress relieved to reduce internal compressive stresses in the tempered martensitic shell to less than 60 ksi and greater than 15 ksi. Such stress relieve stabilizes the rod against break-up as caused by the balancing tensile stresses in the pearlitic core exceeding tensile strength of the core.

Abstract: A process for production of a steel component having a hard, carbon rich dissolved surface and a tough, low carbon dissolved core, incorporating the following steps:using an alloyed steel with a carbon content of 0.3%-1.2% C and with an alloy element acting as a strong carbide former; andsubjecting a component formed from this material to induction heating, whereby the core is heated to a level in the lower region of the austenite area, thereby creating a certain dissolved low carbon level in the component core, and rapidly heating the surface region to a higher region within the austenite area, thereby creating a high dissolved carbon content in the surface region of the component.

Abstract: A CNC method for forging, quenching and tempering a metal material is composed of an automatic process of feeding a metal material, which is uniformly heated at a temperature of 1000.degree. C. for about one minute by an induction coil and is subsequently forged to take form. The forged metal is then checked and quenched. The metal material so treated is finally tempered to have proper texture, consistency, hardness, and toughness.

Abstract: A bumper beam for vehicles is formed from cold-rolled sheet steel having an initial tensile strength of approximately 70 ksi. The steel sheet is roll formed in a desired cross-section and swept into a curvature corresponding to the vehicle requirements before the steel sheet is heat treated by induction heat and quenched to provide a bumper beam having a tensile strength from 100 ksi up to approximately 260 ksi.

Abstract: A method and apparatus for carrying out scaleless inductive heating of ferrous parts comprising (i) using an integrated manifold-inductor quenchant device, and while gradually flowing a diluted combustible gas into the spacing between the inductor and part surface to be heated, inductively heating such surface as part of a heat treating cycle; and (ii) concurrently stopping such flow and injecting a fluid quenchant through the spacing to rapidly lower the temperature of the part surface to complete the heat treating cycle. Advantageously such method may further comprise flushing the spacing between the inductor and heated part surface, and then repeating the steps of the prior method to treat more parts with the same inductor.

Abstract: A production method for an endless track bushing wherein high-carbon low-alloy steel is selected as a bushing material, the bushing material is quench-hardened without pre-carburizing the bushing material, and then tempered. In the quench-hardening, the bushing material is induction-heated from an outside surface of the bushing material only so that an inside surface of the bushing material is heated to a temperature above and close to a transformation temperature of the high-carbon low-alloy steel, and then the heated bushing material is cooled from the outside surface of the bushing material only so that a residual compressive stress is produced at the inside surface of the bushing material when it has been cooled to an ambient temperature. The thus produced bushing has a high hardness throughout the entire cross section and a high toughness.