Class / Patent application number | Description | Number of patent applications / Date published |
148622000 | Ageing, solution treating (i.e., for hardening), precipitation hardening or strengthening | 31 |
20080251165 | Heat treatment system for a composite turbine engine component - A heat treatment process for a component of a turbine engine formed from multiple materials, such as steel and nickel. The heat treatment process includes two stages: a first stage for austinitizing the steel and solutioning the nickel, and a second stage for ageing and tempering the materials. The heat treatment process may include heating a component formed from a steel portion and a nickel portion such that the steel portion austinitizes and the nickel portion undergoes solutioning, cooling the component to prevent the excessive formation of gamma prime ({grave over (γ)}), and subjecting the component to a temper heat treatment during which martensite tempering occurs. | 10-16-2008 |
20100193090 | STEEL FOR MACHINE AND STRUCTURAL USE HAVING EXCELLENT MACHINABILITY AND PROCESS FOR PRODUCING THE SAME - The present invention provides a steel for machine and structural use which is capable of maintaining mechanical characteristics such as strength by reducing a S content as well as of exhibiting excellent machinability (particularly tool life) in intermittent cutting (such as hobbing) with the high speed tool, and a method useful for producing the steel for machine and structural use. The steel for machine and structural use according to the invention secures 0.002% or more of solute N in the steel and has a chemical composition which is appropriately adjusted and satisfies a relationship of the following expression (1): (0.1×[Cr]+[Al])/[O]≧150 . . . (1), in which [Cr], [Al], and [0] represent a Cr content (mass %), an Al content (mass %), and an O content (mass %), respectively. | 08-05-2010 |
20100282377 | METHODS FOR TREATING HIGH-STRENGTH, LOW-ALLOY STEEL - A method for treating high-strength, low-alloy steel includes controlling material responses, such as the crystal structure of the steel, through various processing steps. More specifically, the method includes cold treating the steel to achieve predictable increases in a minimum ultimate tensile strength or desired changes in the crystal structure of the steel. In one embodiment, cold treating the steel operates to controllably increase the minimum ultimate tensile strength of the steel within increasing a specified maximum ultimate tensile strength of the steel. Stated otherwise, cold treating the steel may reduce or narrow a minimum-to-maximum ultimate tensile strength range such that the minimum ultimate tensile strength is closer to the specified maximum ultimate tensile strength. | 11-11-2010 |
20110114233 | DEVELOPMENT OF A HIGH STRENGTH HIGH TOUGHNESS BAINITIC STEEL - A bainitic steel with simultaneous high yield strength and high fracture toughness includes at least 5 volume percent austenite as well as iron, carbon, and silicon. The silicon is present in an amount of at least 1.5 weight percent of total weight of the bainitic steel. A method of forming the steel by austempering is also provided. | 05-19-2011 |
20110186189 | HIGH-STRENGTH COLD-ROLLED STEEL SHEET EXCELLENT IN WORKABILITY AND METHOD FOR MANUFACTURING THE SAME - In a cold-rolled steel sheet in relation with the present invention, metallurgical structure of the steel sheet is made a mixture structure including bainite, residual austenite and tempered martensite, particularly, when the metallurgical structure is observed with a scanning electron microscope, bainite is constituted of composite structure of high temperature range forming bainite with 1 μm or above average distance between neighboring residual austenite and/or carbide and low temperature range forming bainite with below 1 μm average distance between neighboring residual austenite and/or carbide, and when the area ratio of the high temperature range forming bainite with respect to total metallurgical structure is made a and the total area ratio of the low temperature range forming bainite and the tempered martensite with respect to the total metallurgical structure is made b, a: 20-80%, b: 20-80%, and a+b: 70% or above are satisfied. The cold-rolled steel sheet in relation with the present invention is improved in all of the elongation (EL), stretch flange formability (A), and bending properties (R) with a good balance, is excellent in the overall workability, and has 980 MPa or above tensile strength. | 08-04-2011 |
20120080125 | LINK CHAIN SUPERIOR IN LOW TEMPERATURE TOUGHNESS AND HEAT TREATMENT METHOD OF THE SAME - The present invention provides a link chain superior in low temperature toughness comprised of low carbon steel, said link chain characterized in that two-stage high frequency quenching-tempering is performed to give a link chain which has a martensite single phase structure, has an austenite grain size of 9 to 12, further contains in said structure a precipitate comprised of 40 nm or smaller TiC in 90% or more and 80 nm or smaller Ti(C,N) in 10% or less, contains AlN in not more than 0.0003%, and has a −40° C. Charpy impact value of at least 45 J. | 04-05-2012 |
20120132326 | METHOD FOR PRODUCING MARTENSITIC STEEL WITH MIXED HARDENING - A method of producing a martensitic steel including a content of other metals such that it can be hardened by intermetallic compound and carbide precipitation, with an Al content of between 0.4% and 3%. The heat shaping temperature of a last heat shaping pass of the steel is lower than the solubility temperature of aluminum nitrides in the steel, and a treatment temperature for each potential heat treatment after the last heat shaping pass is lower than the solid-state solubility temperature of the aluminum nitrides in the steel. | 05-31-2012 |
20150053315 | BORON-ADDED HIGH STRENGTH STEEL FOR BOLT AND HIGH STRENGTH BOLT HAVING EXCELLENT DELAYED FRACTURE RESISTANCE - Provided are: a boron-added high strength steel for bolt excellent in delayed fracture resistance even having a tensile strength of 1100 MPa or more without addition of large amounts of expensive alloy elements such as Cr and Mo: and a high strength bolt made from the boron-added high strength steel for bolt. The high strength steel for bolt contains C of 0.23% to less than 0.40%, Si of 0.23% to 1.50%, Mn of 0.30% to 1.45%, P of 0.03% or less (excluding 0%), S of 0.03% or less (excluding 0%), Cr of 0.05% to 1.5%, V of 0.02% to 0.30%, Ti of 0.02% to 0.1%, B of 0.0003% to 0.0050%, Al of 0.01% to 0.10%, and N of 0.002% to 0.010%, with the remainder being iron and inevitable impurities. The steel has a ratio ([Si]/[C]) of the Si content [Si] to the C content [C] of 1.0 or more and has a ferrite-pearlite mixed microstructure. | 02-26-2015 |
20160138122 | PRECIPITATION HARDENING STEEL WITH IMPROVED TOUGHNESS AND METHOD - In some aspects, a heat treatment process is described for precipitation hardening steel. The heat treatment process can include a solution treatment for a precipitation hardening steel part. The solution treatment includes heating the precipitation hardening steel part to an austenitizing temperature. The heat treatment process can also include a quenching or cooling treatment, in which the precipitation hardening steel part is cooled to a martensitizing temperature. The heat treatment process can also include an aging treatment, in which the precipitation hardening steel part is heated to a temperature of 1000° F. and held at that temperature for five or more hours until a fracture toughness of the precipitation hardening steel part is greater than 120 ksi√in. | 05-19-2016 |
148623000 | Overageing | 4 |
20120291928 | Process for the Heat Treatment of Metal Strip Material, and Strip Material Produced in that Way - Disclosed is a process for the heat treatment of metal strip material providing mechanical properties that differ over the width of the strip, wherein the strip is heated and cooled and optionally over-aged during a continuous annealing process. At least one of the following parameters in the process differs over the width of the strip: heating rate, top temperature, top temperature holding time, cooling trajectory after top temperature; or, when over-aging is performed, at least one of the following parameters in the process differs over the width of the strip: heating rate, top temperature, top temperature holding time, cooling trajectory after top temperature, over-aging temperature, over-aging temperature holding time, lowest cooling temperature before over-aging, re-heating rate to over-aging temperature. Also, at least one of the cooling trajectories follows a non-linear temperature-time path. Also disclosed is strip material thus produced. | 11-22-2012 |
20140230973 | STEEL SHEET AND METHOD OF PRODUCING THE SAME - A steel sheet of the present invention has a steel structure obtained by performing a soaking at a dual phase region temperature of Ac1 temperature or higher and lower than Ac3 temperature for a soaking time of 15 seconds or longer and 35 seconds or shorter, next, performing a primary cooling to a temperature range of 250° C. or higher and 380° C. or lower within 3 seconds at a cooling rate of 0.5° C./s or more and 30° C./s or less, and performing a retention in a temperature range of 260° C. or higher and 370° C. or lower for 180 seconds or longer and 540 seconds or shorter, in which a yield ratio is 65% or less and tensile strength is 590 MPa or more after the primary cooling. | 08-21-2014 |
20150034218 | HIGH STRENGTH COLD ROLLED STEEL SHEET AND METHOD OF PRODUCING SUCH STEEL SHEET - The present invention relates to high strength cold rolled steel sheet suitable for applications in automobiles, construction materials and the like, specifically high strength steel excellent in formability. In particular, the invention relates to cold rolled steel sheets having a tensile strength of at least 980 MPa and a method for producing such steel sheet. | 02-05-2015 |
20150059935 | HIGH STRENGTH COLD ROLLED STEEL SHEET AND METHOD OF PRODUCING SUCH STEEL SHEET - The present invention relates to high strength cold rolled steel sheet suitable for applications in automobiles, construction materials and the like, specifically high strength steel excellent in formability. In particular, the invention relates to cold rolled steel sheets having a tensile strength of at least 780 MPa. | 03-05-2015 |
148624000 | With working | 18 |
20080251166 | Precipitation Hardening Cold Rolled Steel Sheet Having Excellent Yield Ratios, and the Method for Manufacturing the Same - Disclosed herein is a precipitation hardening cold-rolled steel sheet and method for manufacturing the same, which can be used for structural components such as seat rails and the like of a vehicle body. The steel sheet comprises, by weight %, C: 0.07˜0.1%, Mn: 1.4˜1.7%, P: 0.05˜0.07%, S: 0.005% or less, acid-soluble Al: 0.1˜0.15%, Nb: 0.06˜0.09%, B: 0.0008˜0.0012%, Sb: 0.02˜0.06%, and the balance of Fe and other unavoidable impurities. The steel sheet has a yield strength of 750 MPa or more and a yield ratio of 85% or more, and is free from surface defects due to a very low degree of oxide enrichment on the surface thereof. | 10-16-2008 |
20080302453 | Shaped Steel Excellent in Fire Resistance and Producing Method Therefor - A shaped steel, such as H-shaped steel, excellent in fire resistance, where a flange portion has 50% or more of a ratio of strength, 80% or less of yield ratio, and 100 J or more of impact strength of Charpy impact test at 0° C., wherein the ratio of strength=(proof stress of 0.2% at 600° C.)/(yield strength at room temperature), and a producing method thereof are provided. The shaped steel comprises in mass percent (%): C: 0.03-0.15; Mo: 0.1-0.6; V≦0.35; and N: 0.002-0.012, and the balance being iron and residual impurities, wherein (x) a mol fraction of precipitate of alloy carbides and alloy carbonitrides at 600° C. is 0.3% or more, and (y) the ratio of the mol fraction of precipitate of alloy carbides and alloy carbonitrides at 300° C. to the mol fraction of precipitate of alloy carbides and alloy carbonitrides at 600° C. is 2.0 or less. | 12-11-2008 |
20090020196 | Cold Rolled Steel Sheet Having Aging Resistance and Superior Formability, and Process for Producing the Same - A cold rolled steel sheet, and a method of manufacturing the same, designed to have aging resistance and excellent formability suitable for use in automobile bodies, electronic appliances, and the like. The cold rolled steel sheet comprises in weight %: 0.003% or less of C, 0.003˜0.03% of S, 0.01˜0.1% of Al, 0.02% or less of N, 0.2% or less of P, at least one of 0.03˜0.2% of Mn and 0.005˜0.2% of Cu, and a balance of Fe and other unavoidable impurities. When the steel sheet comprises one of Mn and Cu, the composition of Mn, Cu, and S satisfies at least one relationship: 0.58*Mn/S≦10 and 1≦0.5*Cu/S≦10, and when the steel sheet comprises both Mn and Cu, the composition of Mn, Cu, and S satisfies the relationship: Mn+Cu≦0.3 and 2≦0.5*(Mn+Cu)/S≦20. Participates of MnS, CuS, and (Mn, Cu)S in the steel sheet have an average size of 0.2 μm or less. Since carbon content in a solid solution state in a crystal grain is controlled by fine precipitates of MnS, CuS, or (Mn, Cu)S, the steel sheet has enhanced aging resistance and formability, and has excellent yield strength and strength-ductility. | 01-22-2009 |
20090065106 | Ultra soft high carbon hot-rolled steel sheets and manufacturing method thereof - The present invention provides an ultra soft high carbon hot-rolled steel sheet. The ultra soft high carbon hot-rolled steel sheet contains 0.2% to 0.7% of C, 0.01% to 1.0% of Si, 0.1% to 1.0% of Mn, 0.03% or less of P, 0.035% or less of S, 0.08% or less of Al, 0.01% or less of N, and the balance being Fe and incidental impurities and further contains 0.0010% to 0.0050% of B and 0.05% to 0.30% of Cr in some cases. In the texture of the steel sheet, an average ferrite grain diameter is 20 μm or more, a volume ratio of ferrite grains having a grain diameter of 10 μm or more is 80% or more, and an average carbide grain diameter is in the range of 0.10 to less than 2.0 μm. In addition, the steel sheet is manufactured by the steps, after rough rolling, performing finish rolling at a reduction ratio of 10% or more and at a finish temperature of (Ar | 03-12-2009 |
20090242085 | DUAL PHASE STEEL SHEET WITH GOOD BAKE-HARDENING PROPERTIES - A dual phase steel sheet with good bake-hardening properties is provided. The steel sheet is characterized in containing (in terms of percent by mass) C: no less than 0.06% and less than 0.25%; Si+Al: 0.5 to 3%; Mn: 0.5 to 3%; P: no more than 0.15%; and S: no more than 0.02%; and also meeting the following condition (in terms of space factor) that retained austenite is at least 3%, bainite is at least 30%, and ferrite is no more than 50%, and further characterized in differing in stress larger than 50 MPa before and after application of 2% pre-strain and ensuing heat treatment for paint baking at 170° C. for 20 minutes. The steel sheet has well-balanced strength and workability, exhibits good bake-hardening properties at the time of paint baking, and offers good resistance to natural aging. | 10-01-2009 |
20090314395 | High strength thin-gauge steel sheet excellent in elongation and hole expandability and method of production of same - The present invention provides high strength thin-gauge steel sheet with excellent elongation and hole expandability having a tensile strength of 500 MPa or more and a method of production of high strength thin-gauge steel sheet with excellent elongation and hole expandability enabling production of this on an industrial scale, that is, high strength thin-gauge steel sheet comprised of, by mass %, C: 0.03 to 0.25%, Si: 0.4 to 2.0%, Mn: 0.8 to 3.1%, P≦0.02%, S≦0.02%, Al≦2.0%, N≦0.01%, and a balance of Fe and unavoidable impurities and having a microstructure comprised of ferrite with an area fraction of 10 to 85% and residual austenite with a volume fraction of 1 to 10%, an area fraction of 10% to 60% of tempered martensite, and a balance of bainite. | 12-24-2009 |
20100037994 | METHOD OF PROCESSING MARAGING STEEL - A method of processing a workpiece of maraging steel includes receiving a workpiece of maraging steel that has been subjected to thermomechanical processing at an austenite solutionizing temperature and then directly aging the workpiece of maraging steel at an aging temperature to form precipitates within a microstructure of the workpiece of maraging steel, without any intervening heat treatments between the thermomechanical processing and the direct aging. | 02-18-2010 |
20100084058 | METHOD OF PRODUCING GRAIN-ORIENTED ELECTRICAL STEEL - The invention produces a grain-oriented electrical steel sheet having a primary recrystallization structure in which Goss-oriented crystal grains and crystal grains having a coincidence orientation relationship to the Goss orientation are aligned in the rolling direction. It is characterized heating a slab containing, in mass %, C: 0.025 to 0.10%, Si: 2.5 to 4.5%, Mn: 0.03 to 0.55%, and Al: 0.007 to 0.040% to 1,100 to 1,450° C. or greater; hot rolling the slab to obtain a hot-rolled sheet; annealing the hot-rolled sheet; cold rolling the annealed sheet multiple times with a split-housing reversible cluster rolling mill; and subjecting the cold-rolled sheet to primary recrystallization annealing followed by secondary recrystallization annealing, in which method: (a) a first cold rolling or first and second cold rollings are performed using a small-diameter work roll of 55 mm to less than 105 mm diameter; (b) a second or third cold rolling to a penultimate cold rolling are performed using a large-diameter work roll of 105 mm to less than 150 mm diameter; and (c) a final cold rolling is conducted using a small work roll of a diameter smaller than the diameter of the large-diameter work roll. | 04-08-2010 |
20100132855 | FIRE-RESISTANT STEEL SUPERIOR IN WELD JOINT REHEAT EMBRITTLEMENT RESISTANCE AND TOUGHNESS AND METHOD OF PRODUCTION OF SAME - The present invention provides high temperature strength and fire-resistant steel superior in weld joint reheat embrittlement resistance and toughness which is produced using steel of a room temperature strength of the 400 to 600N/mm | 06-03-2010 |
20110186190 | THERMAL MECHANICAL TREATMENT OF FERROUS ALLOYS, AND RELATED ALLOYS AND ARTICLES - A thermal mechanical treatment method includes hot working a precipitation hardening martensitic stainless steel, quenching the stainless steel, and aging the stainless steel. According to certain embodiments, the thermal mechanical treatment does not include solution heat treating the stainless steel prior to aging or cryogenically cooling the stainless steel. An article includes a precipitation hardening martensitic stainless steel having a process history that includes hot working the stainless steel, quenching the stainless steel, and aging the stainless steel. According to certain embodiments, the process history does not include solution heat treating the stainless steel prior to aging or cryogenically cooling the stainless steel. | 08-04-2011 |
20120018063 | CASE-HARDENED STEEL SUPERIORIN COLD WORKABILITY, MACHINABILITY, AND FATIGUE CHARACTERISTICS AFTER CARBURIZED QUENCHING AND METHOD OF PRODUCTION OF SAME - Cold worked, machined, and carburized quenched case-hardened steel prevented from formation of coarse grains, that is, case-hardened steel superior in cold workability, machinability, and fatigue characteristics after carburized quenching characterized by limiting, by mass %, S: 0.001 to 0.15%, Ti: 0.05 to 0.2%, Al: 0.04% or less, and N: 0.0050% or less, containing other specific ingredients in specific ranges, furthermore containing one or more of Mg: 0.003% or less, Zr: 0.01% or less, and Ca: 0.005% or less, limiting the amount of precipitation of AlN to 0.01% or less, and having a density d (/mm | 01-26-2012 |
20120180911 | METHOD FOR PRODUCING A HOLE IN PLATE MEMBER - The present invention is premised upon a method of piercing a hole through a plate member by removing at least 10% of the hole offal material prior to piercing the hole. In the case of high strength steel plating (e.g. armor plating), the step of annealing before punching may be included, as well as the step of hardening the steel after the punching operation. | 07-19-2012 |
20130167986 | STEEL PART FOR MACHINE STRUCTURAL USE AND MANUFACTURING METHOD THEREOF - The present invention provides a steel part for machine structural use whose fatigue strength and toughness are improved and a manufacturing method thereof. A steel part made of a steel containing, in mass %, C: 0.05 to 0.20%, Si: 0.10 to 1.00%, Mn: 0.75 to 3.00%, P: 0.001 to 0.050%, S: 0.001 to 0.200%, V: exceeding 0.25 to 0.50%, Cr: 0.01 to 1.00%, Al: 0.001 to 0.500%, and N: 0.0080 to 0.0200%, and a balance being composed of Fe and inevitable impurities, in which a steel structure contains a bainite structure having an area ratio of 95% or more, a bainite lath width is 5 μm or less, V carbide having an average grain diameter of not less than 4 nm nor more than 7 nm dispersedly exists in the bainite structure, and an area ratio of V carbide in the bainite structure is 0.18% or more. | 07-04-2013 |
20130186527 | HEAT TREATMENT FOR PRODUCING STEEL SHEET WITH HIGH STRENGTH AND DUCTILITY - The microstructure of a low alloy steel workpiece for cold forming may be beneficially modified by heating the workpiece to a temperature just above its austenite transformation temperature (Ac | 07-25-2013 |
20130186528 | STEEL PART FOR MACHINE STRUCTURAL USE AND MANUFACTURING METHOD THEREOF - The present invention provides a steel part for machine structural use whose fatigue strength and toughness are improved and a manufacturing method thereof. A steel part made of a steel containing, in mass %, C: 0.05 to 0.20%, Si: 0.10 to 1.00%, Mn: 0.75 to 3.00%, P: 0.001 to 0.050%, S: 0.001 to 0.200%, V: 0.05 to 0.20%, Cr: 0.01 to 1.00%, Al: 0.001 to 0.500%, and N: 0.0080 to 0.0200%, and a balance being composed of Fe and inevitable impurities, in which a steel structure contains a bainite structure having an area ratio of 95% or more, a bainite lath width is 5 μm or less, V carbide having an average grain diameter of not less than 4 nm nor more than 7 nm dispersedly exists in the bainite structure, and an area ratio of V carbide in the bainite structure is 0.18% or more. | 07-25-2013 |
20130186529 | STEEL PART FOR MACHINE STRUCTURAL USE AND MANUFACTURING METHOD THEREOF - The present invention provides a steel part for machine structural use whose fatigue strength and toughness are improved and a manufacturing method thereof. A steel part made of a steel containing, in mass %, C: 0.05 to 0.20%, Si: 0.10 to 1.00%, Mn: 0.75 to 3.00%, P: 0.001 to 0.050%, S: 0.001 to 0.200%, V: exceeding 0.20 to 0.25%, Cr: 0.01 to 1.00%, Al: 0.001 to 0.500%, and N: 0.0080 to 0.0200%, and a balance being composed of Fe and inevitable impurities, in which a steel structure contains a bainite structure having an area ratio of 95% or more, a bainite lath width is 5 μm or less, V carbide having an average grain diameter of not less than 4 nm nor more than 7 nm dispersedly exists in the bainite structure, and an area ratio of V carbide in the bainite structure is 0.18% or more. | 07-25-2013 |
20150013856 | METHOD FOR MANUFACTURING PRESS-FORMED PRODUCT AND PRESS-FORMED PRODUCT - In the present invention, a press-formed product is manufactured by heating a steel sheet for hot pressing use to a temperature of 900° C. or above and 1,100° C. or below, the steel sheet for hot pressing use having a predetermined chemical component composition, some of Ti-containing precipitates contained in the steel sheet, each of which having an equivalent circle diameter of 30 nm or less, having an average equivalent circle diameter of 6 nm or less, and the precipitated Ti amount and the total Ti amount in the steel fulfilling the relationship represented by formula (1) shown below, thereafter starting press-forming, and holding at the bottom dead point and cooling to a temperature lower than the martensite transformation starting temperature Ms while securing the average cooling rate of 20° C./s or more within a tool. | 01-15-2015 |
20150376729 | AUSTENITIC STAINLESS STEEL SHEET AND METHOD FOR PRODUCING HIGH ELASTIC LIMIT NONMAGNETIC STEEL MATERIAL USING THE SAME - [Problem] To provide a raw material steel sheet for providing a high strength nonmagnetic austenitic stainless steel material that has a high elastic limit stress and excellent toughness. | 12-31-2015 |