With Titanium(ti) In The Mathematical Relationship Patents (Class 148/507)
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Patent number: 12215397Abstract: Disclosed is a high-yield-ratio cold-rolled dual-phase steel, having the following chemical elements in percentage by mass: 0.05%-0.08% of C, 0.9%-1.2% of Mn, 0.1%-0.6% of Si, 0.030%-0.060% of Nb, 0.030%-0.060% of Ti, 0.015%-0.045% of Al, and the balance being Fe and other inevitable impurities. A manufacturing method for the high-yield-ratio cold-rolled dual-phase steel, comprising: (1) smelting and casting; (2) hot rolling, wherein a casting blank is controlled and soaked at a temperature of 1200° C.-1250° C.; rolled with the finish rolling temperature being 840° C.-930° C.; cooled at a speed of 20° C./s-70° C./s, and then wound at the winding temperature being 570° C.-630° C.; (3) cold rolling; (4) annealing at the soaking temperature being 750° C.-790° C. for 40 s-200 s, cooling at a speed of 30° C./s-80° C./s, the start temperature of cooling is 650° C. to 730° C., the aging temperature is 200° C. to 260° C., and the overaging time is 100 s to 400 s; and (5) leveling.Type: GrantFiled: November 22, 2019Date of Patent: February 4, 2025Assignee: BAOSHAN IRON & STEEL CO., LTD.Inventors: Wei Li, Xiaodong Zhu, Peng Xue
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Patent number: 12134810Abstract: These steel sheet for hot stamping and hot-stamping formed body have predetermined chemical composition and metallographic structures, and, in textures of a surface layer region and an inside region, ratios between a pole density of an orientation group consisting of {001}<1-10> to {001}<?1-10> and a pole density of an orientation group consisting of {111}<1-10> to {111}<?1-12> are controlled.Type: GrantFiled: May 7, 2021Date of Patent: November 5, 2024Assignee: NIPPON STEEL CORPORATIONInventors: Daisuke Maeda, Yuri Toda, Shingo Fujinaka
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Patent number: 12129954Abstract: A seamless steel pipe of the present invention is a seamless steel pipe having a composition including, in mass %, C: 0.01 to 0.12%, Si: 0.01 to 0.8%, Mn: 0.10 to 2.00%, P: 0.050% or less, S: 0.040% or less, Al: 0.010 to 0.100%, Cu: 0.03 to 0.80%, Ni: 0.01 to 0.50%, Mo: 0.01 to 0.20%, Sb: 0.002 to 0.50%, Cr: 0.004% or less, W: 0.002% or less, and the balance Fe and incidental impurities, and a structure including a ferrite phase having an area percentage of 50 to 65%, a pearlite phase having an area percentage of 2% or less, and one or both of a bainite phase and a martensitic phase representing the remainder, the seamless steel pipe having a yield strength of 230 MPa or more, and a tensile strength of 380 MPa or more.Type: GrantFiled: June 12, 2020Date of Patent: October 29, 2024Assignee: JFE Steel CorporationInventors: Hiroyuki Takai, Mitsuhiro Okatsu, Yasumasa Takemura, Tatsuo Koide
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Patent number: 12129534Abstract: This hot-stamping formed body has a predetermined chemical composition and has a metallographic structure consisting of, by area ratio, a total of 10% to 30% of ferrite and granular bainite and a remainder in microstructure consisting of one or more of martensite, bainite, and tempered martensite, and, in textures of a surface layer region and an inside region, ratios between a pole density of an orientation group consisting of {001}<1-10> to {001}<?1-10> and a pole density of an orientation group consisting of {111}<1-10> to {111}<?1-12> are controlled.Type: GrantFiled: May 7, 2021Date of Patent: October 29, 2024Assignee: NIPPON STEEL CORPORATIONInventors: Yuri Toda, Daisuke Maeda, Shingo Fujinaka
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Patent number: 11742140Abstract: Provided is a wound core formed by laminating a plurality of bent bodies obtained by forming a coated grain-oriented electrical steel sheet in which a coating is formed on at least one surface of a grain-oriented electrical steel sheet so that the coating is on an outside, in a sheet thickness direction, in which the bent body has a bent region obtained by bending the coated grain-oriented electrical steel sheet and a flat region adjacent to the bent region, the number of deformation twins present in the bent region in a side view is five or less per 1 mm of a length of a center line in the sheet thickness direction in the bent region, and when a region extending 40 times a sheet thickness to both sides in a circumferential direction from a center of the bent region on an outer circumferential surface of the bent body is defined as a strain affected region, a proportion of an area where the coating is not damaged at any position along the circumferential direction in a flat region within the strain affected rType: GrantFiled: April 27, 2020Date of Patent: August 29, 2023Assignee: NIPPON STEEL CORPORATIONInventors: Takahito Mizumura, Masato Mizokami, Hisashi Mogi, Fumiaki Takahashi
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Patent number: 11572603Abstract: Disclosed is a hot-rolled steel strip having a tensile strength greater than 875 MPa and containing in mass-%: C 0.06-0.12, Si 0-0.5, Mn 0.70-2.20, Nb 0.005-0.100, Ti 0.01-0.10, V 0.11-0.40, whereby the total amount of V+Nb+Ti is 0.20-0.40 Al 0.005-0.150, B 0-0.0008, Cr 0-1.0, whereby the total amount of Mn+Cr is 0.9-2.5, Mo 0-0.5, Cu 0-0.5, Ni 0-1.0, P 0-0.05, S 0-0.01, Zr 0-0.1 Co 0-0.1 W 0-0.1 Ca 0-0.005, N 0-0.01, balance Fe and unavoidable impurities, and having a microstructure at ¼ thickness that is: at least 90% martensite and bainite with island-shaped martensite-austenite (MA) constituents, the remainder being: less than 5% polygonal ferrite and quasi-polygonal ferrite, less than 5% pearlite, less than 5% austenite, so that the total area percentage is 100%.Type: GrantFiled: November 13, 2019Date of Patent: February 7, 2023Assignee: SSAB TECHNOLOGY ABInventors: Mikko Hemmilä, Tommi Liimatainen, Ari Hirvi
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Patent number: 11492689Abstract: The rail having a chemical composition containing C: 0.70-1.00 mass %, Si: 0.50-1.60 mass %, Mn: 0.20-1.00 mass %, P: ?0.035 mass %, S: ?0.012 mass %, Cr: 0.40-1.30 mass %, where Ceq defined by the formula (1) is 1.04-1.25, Ceq=[% C]+([% Si]/11)+([% Mn]/7)+([% Cr]/5.8)??(1) where [% M] is the content in mass % of the element M, the balance being Fe and inevitable impurities, where Ceq(max) is ?1.40, where the Ceq(max) is determined by the formula (2) using maximum contents of C, Si, Mn, and Cr obtained by subjecting a region between specified positions to EPMA line analysis; and a pearlite area ratio in the region is 95% or more, Ceq(max)=[% C(max)]+([% Si(max)]/11)+([% Mn(max)]/7)+([% Cr(max)]/5.8)??(2) where [% M(max)] is the maximum content of the element M.Type: GrantFiled: March 28, 2019Date of Patent: November 8, 2022Assignee: JFE STEEL CORPORATIONInventors: Keisuke Ando, Tatsumi Kimura, Satoshi Igi
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Patent number: 11142805Abstract: Provided are a high-strength coated steel sheet and a method for manufacturing the same. The high-strength coated steel sheet has a base steel sheet and a coating layer formed on a surface of the base steel sheet. The base steel sheet has a specified chemical composition and a microstructure, including a martensite phase and a ferrite phase. A volume fraction of the martensite phase is 50% to 80%. A volume fraction of tempered martensite with respect to the whole martensite phase is 50% or more and 85% or less. An average grain diameter of the ferrite phase is 13 ?m or less. A volume fraction of ferrite grains having an aspect ratio of 2.0 or less with respect to the whole ferrite phase is 70% or more. Yield strength (YP) of the high-strength coated steel sheet is 550 MPa or more.Type: GrantFiled: September 28, 2017Date of Patent: October 12, 2021Assignee: JFE Steel CorporationInventors: Lingling Yang, Noriaki Kohsaka, Tatsuya Nakagaito, Yoshimasa Funakawa
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Patent number: 11091817Abstract: Provided are a high-strength steel sheet having high strength of a yield strength of 550 MPa or more and a method for manufacturing the same. The high-strength steel sheet has a specified chemical composition and a microstructure, where observed in a cross section in a thickness direction perpendicular to a rolling direction, including a martensite phase having a volume fraction of 50% to 80%, and a ferrite phase having an average grain diameter of 13 ?m or less, wherein a volume fraction of ferrite grains having an aspect ratio of 2.0 or less with respect to the whole ferrite phase is 70% or more, and wherein an average length in a longitudinal direction (in a width direction of the steel sheet) of the ferrite grains is 20 ?m or less, and a yield strength (YP) of 550 MPa or more.Type: GrantFiled: August 29, 2017Date of Patent: August 17, 2021Assignee: JFE Steel CorporationInventors: Lingling Yang, Noriaki Kohsaka, Tatsuya Nakagaito, Yoshimasa Funakawa
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Patent number: 10858716Abstract: The present invention provides a hot rolled steel sheet with yield stress greater than 680 MPa and less than or equal to 840 MPa a tensile strength between 780 MPa and 950 MPa, elongation at failure greater than 10% and hole-expansion ratio (Ac) greater than or equal to 45%. The chemical composition includes, with the contents expressed by weight: 0.05%?Mo?0.35%, 0.15<C?0.6% when 0.05%?Mo?0.11%, or 0.10%?Cr?0.6% when 0.11%<Mo?0.35%. The microstructure includes at least 70% granular bainite, less than 20% ferrite, with the remainder, if any, including lower bainite, martensite and residual austenite. The sum of the martensite and residual austenite contents is less than 5%.Type: GrantFiled: July 10, 2015Date of Patent: December 8, 2020Assignee: ArcelorMittalInventors: Jean Marc Pipard, Astrid Perlade, Bastien Weber, Florence Pechenot, Aurelie Milani
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Patent number: 10763517Abstract: A stainless steel sheet for fuel cell separators comprises: a predetermined chemical composition; and fine precipitates containing Cr and Ti at a steel sheet surface, wherein an average equivalent circular diameter of the fine precipitates is 20 nm or more and 500 nm or less, and a number of the fine precipitates existing per 1 ?m2 at the steel sheet surface is three or more.Type: GrantFiled: May 22, 2017Date of Patent: September 1, 2020Assignee: JFE STEEL CORPORATIONInventors: Takayoshi Yano, Shin Ishikawa
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Patent number: 10612107Abstract: The invention deals with a cold rolled and hot dip steel sheet, with a tensile strength of at least 980 MPa, with yield strength above or equal to 500 MPa, with total elongation above or equal to 8%, the composition consisting by weight percent: 0.05<C<0.15%, 2<Mn?3%, Al<0.1%, 0.3<Si<1.5%, 0.01%<Nb<0.05%, N<0.02%, 0.1<Cr+Mo<1%, 0.0001<B<0.0025, Ti<0.5%, V<0.01%, S<0.01%, P<0.05% the remainder of the composition being iron and unavoidable impurities resulting from the smelting and the microstructure contains, in surface fraction: between 50 and 95% of martensite and between 5 and 50% of the sum of ferrite and bainite, wherein the ferrite grain size is below 10????, and wherein the aspect ratio of the ferrite grain size is between 1 and 3. The steel according to the invention is oxidized and subsequently reduced during heating, soaking and cooling steps of the annealing.Type: GrantFiled: June 3, 2015Date of Patent: April 7, 2020Assignee: ARCELORMITTALInventors: Dongwei Fan, Hyun Jo Jun, John A. Rotole
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Patent number: 10400295Abstract: The invention is directed to a method for processing asbestos-containing steel scrap into useful products, which products can be handled in a safe manner. In accordance with the present invention the asbestos-containing steel scrap is melted in a furnace, which results in destruction of the asbestos fibers. It has been found possible to carry out such a process in an economically feasible manner. In accordance with the invention asbestos-containing steel is heated to high temperature so that the steel melts. As a result the asbestos will be converted into harmless material, which allows for safe handling and processing of the resulting products.Type: GrantFiled: December 23, 2014Date of Patent: September 3, 2019Assignee: PMC International B.V.Inventor: Klaas Jansen
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Patent number: 10385419Abstract: The present invention provides steel sheet products having controlled compositions that are subjected to two-step annealing processes to produce sheet products having desirable microstructures and favorable mechanical properties such as high strength and ultra-high formability. Steels processed in accordance with the present invention exhibit combined ultimate tensile strength and total elongation (UTS·TE) properties of greater than 25,000 MPa-%. Steels with these properties fall into the category of Generation 3 advanced high strength steels, and are highly desired by various industries including automobile manufacturers.Type: GrantFiled: May 10, 2017Date of Patent: August 20, 2019Assignee: United States Steel CorporationInventors: David Paul Hoydick, Eduardo Augusto Silva, Matthew Michael McCosby
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Patent number: 10344351Abstract: A hot-pressed steel sheet member includes: a specific chemical composition; and a steel microstructure represented by, in area %, ferrite: 10% to 70%, martensite: 30% to 90%, and a total area ratio of ferrite and martensite: 90% to 100%. 90% or more of all Ti in steel precipitates, and a tensile strength of the hot-pressed steel sheet member is 980 MPa or more.Type: GrantFiled: December 20, 2013Date of Patent: July 9, 2019Assignee: NIPPON STEEL & SUMITOMO METAL CORPORATIONInventors: Koutarou Hayashi, Toshinobu Nishibata
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Patent number: 10173281Abstract: Disclosed herein are bonded structures and methods of forming the same. One embodiment of a bonded structure comprises first and second metallic layers and a bonding interface between the first and second metallic layers formed by diffusion and comprising a layer of at least one intermetallic compound. The intermetallic compound layer is formed in an area 52% or greater of an area of the bonding interface and has a thickness of 0.5 to 3.2 ?m.Type: GrantFiled: January 31, 2014Date of Patent: January 8, 2019Assignee: Nissan Motor Co., Ltd.Inventors: Hiroshi Sakurai, Shigeyuki Nakagawa, Akira Fukushima, Sadao Yanagida, Chika Sugi
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Patent number: 9821534Abstract: A galvannealed steel sheet includes a zinc coating layer containing 7 to 15% Fe on the surface of steel sheet including, C: 0.02% to 0.30%, Si: 0.01% to 2.5%, Mn: 0.1% to 3.0%, P: 0.003% to 0.08%, S: not more than 0.01%, Al: 0.001% to 0.20%, one or more selected from Ti: 0.03% to 0.40%, Nb: 0.001% to 0.2%, V: 0.001% to 0.2%, Mo: 0.01% to 0.5% and W: 0.001% to 0.2%. In the zinc coating layer, carbides with average particle size of 1 nm to 20 nm including one or more selected from titanium, niobium, vanadium, molybdenum and tungsten are present with a density of five or more particles per segment that is defined by the thickness of the coating layer and also by dividing a cross section of the coating layer at intervals of 1 ?m in a direction perpendicular to the thickness of the coating layer.Type: GrantFiled: June 15, 2012Date of Patent: November 21, 2017Assignee: JFE STEEL CORPORATIONInventors: Daisuke Harako, Yusuke Fushiwaki, Yoshitsugu Suzuki, Yasunobu Nagataki
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Patent number: 9657380Abstract: A slab has a steel composition including 0.020% to 0.065% of C, 0.1% or less of Si, 0.40% to less than 0.80% of Mn, 0.030% or less of P, 0.005% or less of S, 0.08% to 0.16% of Ti, 0.005% to 0.1% of Al, 0.005% or less of N, and the balance being Fe and incidental impurities, in which Ti*(=Ti?(48/14)×N) satisfies [Ti*?0.08] and [0.300?C/Ti*?0.375], is subjected to hot rolling to obtain a hot-rolled steel sheet in which the steel microstructure includes, in terms of area fraction, 95% or more of a ferrite phase; the average ferrite grain size is 10 ?m or less; the average grain size of Ti carbides precipitated in steel is 10 nm or less; and Ti in the amount of 80% or more of Ti* is precipitated as Ti carbides.Type: GrantFiled: April 26, 2012Date of Patent: May 23, 2017Assignee: JFE Steel CorporationInventors: Noriaki Kosaka, Kazuhiro Seto, Hidetaka Kawabe
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Publication number: 20150101898Abstract: The present invention is directed to a stainless steel brake disc which is excellent in toughness, corrosion resistance, and wear resistance, and comprises, in % by mass, 0.030 to 0.080% of C, 0.05% to 1.0% of Si, 1.0 to 1.5% of Mn, 0.035% or less of P, 0.015% or less of S, 11.0 to 14.0% of Cr, 0.01 to 0.50% of Ni, 0.001 to 0.15% of V, less than 0.1% of Nb, 0.05% or less of Ti, 0.05% or less of Zr, 0.05% or less of Al, 0.015 to 0.060% of N, 0.0002% or more and 0.0050% or less of B, and 0.0080% or less of O, wherein an AT value of equation 1 is 0.055 to 0.090, equation 2 is satisfied, a ferrite phase fraction, in which an IQ value of an EBSD pattern is 4,000 or more, is 1% to 15%, a Charpy impact value is 50 J/cm2 or more, and hardness is 32 to 38 HRC. C+0.8(N?B)??(1) PV=1.2Ti+0.8Zr+Nb+1.1Al+O?0.Type: ApplicationFiled: February 7, 2014Publication date: April 16, 2015Applicant: NIPPON STEEL & SUMIKIN STAINLESS STEEL CORPORATIONInventors: Shinichi Teraoka, Yoshiharu Inoue, Yuji Koyama, Masaaki Kobayashi, Toshio Tanoue
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Publication number: 20150030879Abstract: A semi-manufactured steel material has a chemical composition including, by mass %, C: 0.055% to 0.15%, Si: not more than 0.2%, Mn: not more than 1.3%, P: not more than 0.03%, S: not more than 0.007%, Al: not more than 0.1%, N: not more than 0.01%, and Ti: 0.14% to 0.30%, the balance comprising Fe and inevitable impurities. In the composition, 1.0 ([C]/12)/([Ti*]/48) is satisfied ([C], [S], [N] and [Ti]: contents (mass %) of the respective elements, and [Ti*]=[Ti]?3.4×[N]?1.5×[S]), and the contents of niobium and boron as impurities are limited to Nb: less than 0.03% and B: less than 0.0005%.Type: ApplicationFiled: December 25, 2012Publication date: January 29, 2015Inventors: Noriaki Kosaka, Yoshimasa Funakawa, Masato Shigemi, Hidekazu Ookubo, Tokunori Kanemura
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Publication number: 20150027594Abstract: A thin steel sheet having sheet thickness ?1.6 mm, but tensile strength ?780 MPa and Young's modulus ?240 GPa in transverse direction is provided, where the steel sheet has composition including, in mass %, C: 0.06-0.12%, Si: 0.5-1.5%, Mn: 1.0-3.0%, P: 0.05% or less, S: 0.01% or less, Al: 0.5% or less, N: 0.01% or less, Ti: 0.02-0.20%, and the balance being Fe and incidental impurities, where the composition satisfies relations of Formula (1) and (2), and microstructure such that ferrite phase has area ratio ?60% and martensite phase has area ratio of 15-35%, ferrite and martensite phases are 95% or more in total, average grain size of ferrite is ?4.0 ?m and that of martensite is ?1.5 ?m, 0.05?[% C]?(12/47.9)×[% Ti*]?0.10 ??(1), where Ti*=[% Ti]?(47.9/14)×[% N]?(47.9/32.1)×[% S]??(2).Type: ApplicationFiled: November 7, 2012Publication date: January 29, 2015Inventors: Kenji Kawamura, Takeshi Yokota
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Publication number: 20150007911Abstract: A method of the present invention includes the steps of heating a steel sheet for hot pressing use to a temperature of Ac3 transformation point or above and 950° C. or below, the steel sheet for hot pressing use containing 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 3 nm or more, 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 being held at the bottom dead point and being cooled to a temperature lower than martensite transformation starting temperature Ms while securing the average cooling rate of 20° C./s or more within a tool. Precipitated Ti amount (mass %)?3.4[N]?0.5×[total Ti amount (mass %)?3.4[N]]??(1) (In the formula (1), [N] represents the content (mass %) of N in the steel.Type: ApplicationFiled: March 1, 2013Publication date: January 8, 2015Applicant: Kabushiki Kaisha Kobe Seiko Sho (Kobe Steel, Ltd.)Inventors: Toshio Murakami, Hideo Hata, Junya Naitou, Keisuke Okita, Shushi Ikeda
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Publication number: 20140366994Abstract: A steel sheet and a method for producing the same are disclosed. The steel sheet has a composition containing 0.015% to 0.05% C, less than 0.10% Si, 0.1% to 2.0% Mn, 0.20% or less P, 0.1% or less S, 0.01% to 0.10% Al, 0.005% or less N, and 0.06% to 0.5% Ti in percent by mass, C and Ti satisfying the inequality Ti*/C?4, where Ti* (mass percent)=Ti-3.4N and Ti, C, and N represent the content (mass percent) of each element. The steel sheet has a microstructure which contains a ferrite phase as a base, in which the average grain diameter of the ferrite phase is 7 ?m or more, and in which the ratio of the rolling-direction average grain diameter to thickness-wise average grain diameter of the ferrite phase is 1.1 or more.Type: ApplicationFiled: December 10, 2012Publication date: December 18, 2014Applicant: JFE STEEL CORPORATIONInventors: Taro Kizu, Koichiro Fujita
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Publication number: 20140338796Abstract: Provided is a ferrite-based stainless steel having superior moldability when molding a fuel cell divider sheet from a material by controlling yield point elongation in accordance with alloy components. The ferrite-based stainless steel comprises, in weight percentages: no more than 0.02% of C; no more than 0.02% of N; no more than 0.4% of Si; no more than 0.2% of Mn; no more than 0.04% of P; no more than 0.02% of S; 25.0-32.0% of Cr; 0-1.0% of Cu; no more than 0.8% of Ni; no more than 0.01-0.5% of Ti; no more than 0.01-0.5% of Nb; no more than 0.01-1.5% of V; and residual Fe and inevitable elements, wherein the content of Ti, Nb, V, C, and N in terms of weight % of steel uses Formula (1) to render a yield point elongation of the material of no more than 1.1%, and wherein a steel material has superior moldability. 9.1C?1.76V+5.37(C+N)/Ti?1.22Nb?0.7.Type: ApplicationFiled: December 26, 2012Publication date: November 20, 2014Inventors: Jong Hee Kim, Ki-Hoon Jo, Yang Jin Chung, Yun Yong Lee, Sang Woo Lee
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Patent number: 8801876Abstract: [Problem to be Solved] A Ni-based alloy product consisting of, by mass percent, C: 0.03 to 0.10%, Si: 0.05 to 1.0%, Mn: 0.1 to 1.5%, Sol.Al: 0.0005 to 0.04%, Fe: 20 to 30%, Cr: not less than 21.0% and less than 25.0%, W: exceeding 6.0% and not more than 9.0%, Ti: 0.05 to 0.2%, Nb: 0.05 to 0.35%, and B: 0.0005 to 0.006%, the balance being Ni and impurities, the impurities being P: 0.03% or less, S: 0.01% or less, N: less than 0.010%, Mo: less than 0.5%, and Co: 0.8% or less, wherein a value of effective B (Beff) defined by the formula, Beff (%)=B?(11/14)×N+(11/48)×Ti, is 0.0050 to 0.0300%, and the rupture elongation in a tensile test at 700° C. and at a strain rate of 10?6/sec is 20% or more. This alloy may contain one or more kinds of Cu, Ta, Zr, Mg, Ca, REM, and Pd.Type: GrantFiled: March 15, 2012Date of Patent: August 12, 2014Assignee: Nippon Steel & Sumitomo Metal CorporationInventors: Atsuro Iseda, Hiroyuki Hirata, Hirokazu Okada, Hiroyuki Semba
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Patent number: 8747576Abstract: This high-carbon pearlitic steel rail having excellent ductility, includes: in terms of percent by mass, C: more than 0.85% to 1.40%; Si: 0.10% to 2.00%; Mn: 0.10% to 2.00%; Ti: 0.001% to 0.01%; V: 0.005% to 0.20%; and N: less than 0.0040%, with the balance being Fe and inevitable impurities, wherein contents of Ti and V fulfill the following formula (1), and a rail head portion has a pearlite structure.Type: GrantFiled: April 14, 2010Date of Patent: June 10, 2014Assignee: Nippon Steel & Sumitomo Metal CorporationInventors: Teruhisa Miyazaki, Masaharu Ueda, Suguru Yoshida
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Publication number: 20140141280Abstract: Provided is a high-strength steel sheet having good warm press formability and excellent strength and ductility after warm press forming, and a method for manufacturing such. The high-strength steel sheet has a tensile strength at room temperature not less than 780 MPa, a yield stress at a heating temperature range of 400° C. to 700° C. not more than 80% of the yield stress at room temperature, total elongation at the heating temperature range not less than 1.1 times the total elongation at room temperature, yield stress and total elongation after the steel sheet is heated to the heating temperature range, subjected to a strain of not more than 20%, and cooled from the heating temperature to room temperature, not less than 70% of the yield stress and total elongation, respectively, at room temperature before the heating.Type: ApplicationFiled: July 11, 2012Publication date: May 22, 2014Applicant: JFE Steel CorporationInventors: Noriaki Kosaka, Yoshimasa Funakawa, Masato Shigemi, Hidekazu Okubo
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Patent number: 8691030Abstract: The present application describes a steel composition that provides enhanced corrosion resistance. This steel composition includes one of vanadium in an amount of 1 wt % to 9 wt %, titanium in an amount of about 1 wt % to 9 wt %, and a combination of vanadium and titanium in an amount of 1 wt % to about 9 wt %. In addition, the steel composition includes carbon in an amount of 0.03 wt % to about 0.45 wt %, manganese in an amount up to 2 wt % and silicon in an amount up to 0.45 wt %. In one embodiment, the steel composition includes a microstructure of one of the following: ferrite, martensite, tempered martensite, dual phase ferrite and martensite, and dual phase ferrite and tempered martensite. Further, the present application describes a method for processing the steel composition and use of equipment such as oil country tubular goods, fabricated with the steel composition.Type: GrantFiled: May 2, 2008Date of Patent: April 8, 2014Assignee: ExxonMobil Upstream Research CompanyInventors: Dylan V. Pugh, Joseph C. Bondos, Shiun Ling, Raghavan Ayer, Shalawn K. Jackson, Jayoung Koo, Swarupa S. Bangaru
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Publication number: 20130327447Abstract: A high strength corrosion resistant tubing comprises about 35 to about 55% Ni, about 12 to about 25% Cr, about 0.5 to about 5% Mo, up to about 3% Cu, about 2.1 to about 4.5% Nb, about 0.5 to about 3% Ti, about 0.05 to about 1.0% Al, about 0.005 to about 0.04% C, balance Fe plus incidental impurities and deoxidizers. The composition also satisfies the equation: (Nb?7.75 C)/(Al+Ti)=about 0.5 to about 9. A process for manufacturing the tubing includes: extruding the alloy to form a tubing; cold working the extruded tubing; annealing the cold worked tubing; and applying at least one age hardening step to the annealed tubing. Another process includes extruding the alloy at a temperature of about 2050° F. or less; annealing the extruded tubing; and applying at least one age hardening step to the annealed tubing.Type: ApplicationFiled: June 11, 2012Publication date: December 12, 2013Applicant: HUNTINGTON ALLOYS CORPORATIONInventor: Sarwan K. Mannan
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Publication number: 20130309525Abstract: A value of a parameter Q represented by “Q=([Ti]/48+[V]/51+[Zr]/91+[Nb]/93)/([C]/12)” is not less than 0.9 nor more than 1.1, when contents of Ti, V, Zr, Nb, and C (mass %) are represented as [Ti], [V], [Zr], [Nb], and [C] respectively. A matrix of a metal structure is a ferrite phase, and the metal structure does not contain a non-recrystallized structure. An average grain size of ferrite grains constituting the ferrite phase is not less than 30 ?m nor more than 200 ?m. A precipitate containing at least one selected from the group consisting of Ti, V, Zr, and Nb exists with a density of 1 particle/?m3 or more in the ferrite grain. An average grain size of the precipitate is not less than 0.002 ?m nor more than 0.2 ?m.Type: ApplicationFiled: August 17, 2012Publication date: November 21, 2013Applicant: NIPPON STEEL & SUMITOMO METAL CORPORATIONInventors: Masahiro Fujikura, Yoshiyuki Ushigami, Tesshu Murakawa, Shinichi Kanao, Makoto Atake, Takeru Ichie, Kojiro Hori, Shinichi Matsui
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Publication number: 20130213529Abstract: A high-strength cold rolled steel sheet having excellent deep drawability and bake hardenability, with a tensile strength ?440 MPa, an average r-value ?1.20 and a bake hardening value ?40 MPa, is obtained by subjecting a steel raw material having a chemical composition including C: 0.010-0.06 mass %, Si: more than 0C:\Users\ejensen\Desktop\!TEMP\.5 mass % but not more than 1.5 mass %, Mn: 1.0-3.0 mass %, Nb: 0.010-0.090 mass %, Ti: 0.015-0.15 mass % and satisfying (Nb/93)/(C/12)<0.20 to hot rolling, cold rolling and then to annealing including steps of heating to a temperature of 800-900° C. while a temperature region of 700-800° C. is an average heating rate <3° C./s, and soaking and thereafter cooling at a rate ?5° C./s from the soaking temperature to a cooling stop temperature ?500° C. to thereby form a microstructure including ferrite phase with an area ratio ?70% and martensite phase with an area ratio ?3%.Type: ApplicationFiled: October 28, 2011Publication date: August 22, 2013Applicant: JFE Steel CorporationInventors: Hideyuki Kimura, Yasunobu Nagataki
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Publication number: 20130186523Abstract: Described are a high tensile strength galvanized steel sheet with high strength and excellent formability (elongation and stretch-flange ability), and manufacturing method. Tensile strength ?980 MPa and excellent formability, having (i) defined composition ranges for C, Si, Mn, P, S, N, Al, Ti, V, Solute V, Solute Ti, and Fe and incidental impurities, (ii) microstructure with fine carbides dispersion precipitated therein, the fine carbides containing Ti and V and having the average particle diameter <10 nm, and volume ratio with respect to the entire microstructure ?0.007, and (iii) matrix as ferrite phase having area ratio with respect to the entire microstructure ?97%; and hot-dip galvanized/galvannealed coating on a surface of the hot rolled steel sheet. Contents of C, Ti, V, S, N satisfy (1) Ti?0.10+N/14*48+S/32*48) and (2) 0.8?(Ti/48+V/51)/(C/12)?1.2.Type: ApplicationFiled: March 30, 2011Publication date: July 25, 2013Applicant: JFE STEEL CORPORATIONInventors: Tamako Ariga, Katsumi Nakajima, Yoshimasa Funkawa
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Patent number: 8465601Abstract: A high carbon steel sheet having superior strength and ductility and a method for manufacturing the same comprising: 0.2 to 1.0 wt % carbon (C), 0 to 3.0 wt % silicon (Si), 0 to 3.0 wt % manganese (Mn), 0 to 3.0 wt % chromium (Cr), 0 to 3.0 wt % nickel (Ni), 0 to 0.5 wt % molybdenum (Mo), 0 to 3.0 wt % aluminum (Al), 0 to 0.01 wt % boron (B), 0 to 0.5 wt % titanium (Ti), and the remainder substantially being iron (Fe) and inevitable impurities. The contents of carbon, manganese, chromium, and nickel satisfy the following Equation 1, and the contents of silicon and aluminum satisfy the following Equation 2: (3.0?2.5×C)wt %?(Mn+Cr+Ni/2)?8.5 wt %—(Equation 1) Si+Al>1.0 wt % (Equation 2).Type: GrantFiled: December 5, 2008Date of Patent: June 18, 2013Assignee: POSCOInventors: Young-Roc Im, Jae-Kon Lee, Kyoo-Young Lee, Yeong-Woo Jeon, Jae-Hwa Ryu, Kyong-Su Park
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Patent number: 8465604Abstract: A ferritic stainless steel sheet having excellent corrosion resistance and a method of manufacturing the steel sheet are provided. Specifically, the ferritic stainless steel sheet of the invention contains C of 0.03% or less, Si of 1.0% or less, Mn of 0.5% or less, P of 0.04% or less, S of 0.02% or less, Al of 0.1% or less, Cr of 20.5% to 22.5%, Cu of 0.3% to 0.8%, Ni of 1.0% or less, Ti of 4×(C %+N %) to 0.35%, Nb of less than 0.01%, N of 0.03% or less, and C+N of 0.05% or less, and has the remainder including Fe and inevitable impurities, wherein 240+35×(Cr %?20.5)+280×{Ti %?4×(C %+N %)}?280 is satisfied.Type: GrantFiled: July 31, 2006Date of Patent: June 18, 2013Assignee: JFE Steel CorporationInventors: Kazuhide Ishii, Tomohiro Ishii, Osamu Furukimi
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Publication number: 20130087252Abstract: A high-strength hot-rolled steel sheet has a composition including C: 0.005% or more and 0.050% or less, Si: 0.2% or less, Mn: 0.8% or less, P: 0.025% or less, S: 0.01% or less, N: 0.01% or less, Al: 0.06% or less, and Ti: 0.05% or more and 0.10% or less, on a mass percent basis, such that S, N, and Ti satisfy Ti?0.04+(N/14×48+S/32×48), the remainder being Fe and incidental impurities; a matrix in which a ferrite phase constitutes 95% by area or more of the entire structure; and a structure in which Ti-containing fine carbide having an average grain size of less than 10 nm is dispersedly precipitated, and the volume ratio of the fine carbide to the entire structure is 0.0007 or more.Type: ApplicationFiled: June 24, 2011Publication date: April 11, 2013Applicant: JFE STEEL CORPORATIONInventors: Tamako Ariga, Katsumi Nakajima, Yoshimasa Funakawa, Noriaki Moriyasu, Takayuki Murata
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Publication number: 20130000791Abstract: On a cross section with a sheet width direction of a high-strength hot-rolled steel sheet set as a normal line, with regard to an inclusion having a major diameter of 3.0 ?m or more, a maximum of a major diameter/minor diameter ratio expressed by (a major diameter of the inclusion)/(a minor diameter of the inclusion) is 8.0 or less, and a sum total of a rolling direction length per 1 mm2 cross section of a predetermined inclusion group composed of plural inclusions each having a major diameter of 3.0 ?m or more and a predetermined extended inclusion having a length in a rolling direction of 30 ?m or more is 0.25 mm or less. The plural inclusions composing the predetermined inclusion group congregate in both the rolling direction and a direction perpendicular to the rolling direction 50 ?m or less apart from each other. The predetermined extended inclusion is spaced over 50 ?m apart from all the inclusions each having a major diameter of 3.Type: ApplicationFiled: March 9, 2011Publication date: January 3, 2013Inventors: Yuzo Takahashi, Junji Haji, Osamu Kawano
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Publication number: 20120279616Abstract: The present invention provides a steel material for hardening, including chemical components, by mass %, of: C: 0.15 to 0.60%; Si: 0.01 to 1.5%; Mn: 0.05 to 2.5%; P: 0.005 to 0.20%; S: 0.001 to 0.35%; Al: over 0.06 to 0.3%; and total N: 0.006 to 0.03%, with a balance including Fe and inevitable impurities including B of not more than 0.0004%, in which a hardness R at a position 5 mm away from a quenching end measured through a Jominy-type end-quenching method specified in JIS G 0561, and a calculation hardness H at a position 4.763 mm away from the quenching end satisfy the following Equation (1). H×0.948?R?H×1.Type: ApplicationFiled: May 17, 2011Publication date: November 8, 2012Inventors: Kei Miyanishi, Manabu Kubota, Shuji Kozawa
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Patent number: 8298356Abstract: The ultrahigh-strength steel sheet contains, in mass %, C: 0.05-0.25%, Si: 1.00-2.5%, Mn: 2.0-4.0%, P: 0.1% or below (not inclusive of 0%), S: 0.05% or below (not inclusive of 0%), Al: 0.01-0.15%, Ti: 0.003-0.10%, N: 0.01% or below (not inclusive of 0%), the balance comprising iron with inevitable impurities, and is a composite structure steel sheet comprising 10-50 area % ferrite and 50 area % or above martensite, in which the average circle-equivalent grain diameter of ferrite grains is 2.0 ?m or below, the average aspect ratio of ferrite grains is 2.0 or below, and the tensile strength is 1,100 MPa or above. Accordingly, the ultrahigh-strength steel sheet is excellent in hydrogen embrittlement resistance and workability.Type: GrantFiled: November 2, 2009Date of Patent: October 30, 2012Assignee: Kobe Steel, Ltd.Inventors: Muneaki Ikeda, Yukihiro Utsumi
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Publication number: 20120241052Abstract: The present disclosure relates to a ferritic stainless steel and fabrication method of a ferritic stainless steel comprising, by weight %, C: above 0 wt % to 0.01 wt % or less, Si: above 0 wt % to 0.5 wt % or less, Mn: above 0 wt % to 2.0 wt % or less, P: 0 wt % or more to 0.04 wt % or less, S: 0 wt % or more to 0.02 wt % or less, Cr: 12 wt % or more to 19 wt % or less, Mo: 0 wt % or more to 1.0 wt % or less, W: 2 wt % of more to 7 wt % or less, Ti: 0 wt % or more to 0.3 wt % or less, Nb: above 0 wt % to 0.6 wt % or less, N: above 0 wt % to 0.01 wt % or less, Al: 0 wt % or more to 0.1 wt % or less; and the balance of Fe and other inevitable impurities.Type: ApplicationFiled: December 23, 2011Publication date: September 27, 2012Inventors: Sang-Seok Kim, Do-leal Yoo, Bo-Sung Seo
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Publication number: 20120168038Abstract: [Problem to be Solved] A Ni-based alloy product consisting of, by mass percent, C: 0.03 to 0.10%, Si: 0.05 to 1.0%, Mn: 0.1 to 1.5%, Sol.Al: 0.0005 to 0.04%, Fe: 20 to 30%, Cr: not less than 21.0% and less than 25.0%, W: exceeding 6.0% and not more than 9.0%, Ti: 0.05 to 0.2%, Nb: 0.05 to 0.35%, and B: 0.0005 to 0.006%, the balance being Ni and impurities, the impurities being P: 0.03% or less, S: 0.01% or less, N: less than 0.010%, Mo: less than 0.5%, and Co: 0.8% or less, wherein a value of effective B (Beff) defined by the formula, Beff (%)=B?(11/14)×N+(11/48)×Ti, is 0.0050 to 0.0300%, and the rupture elongation in a tensile test at 700° C. and at a strain rate of 10?6/sec is 20% or more. This alloy may contain one or more kinds of Cu, Ta, Zr, Mg, Ca, REM, and Pd.Type: ApplicationFiled: March 15, 2012Publication date: July 5, 2012Applicant: SUMITOMO METAL INDUSTRIES, LTD.Inventors: Atsuro ISEDA, Hiroyuki HIRATA, Hirokazu OKADA, Hiroyuki SEMBA
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Patent number: 8137483Abstract: A method of designing low cost, high strength, high toughness martensitic steel uses mathematical modeling to define optimum low cost chemical compositions, the content of retained austenite, and critical temperatures; melting an ingot, processing same, making steel articles, and heat treating the articles using the critical temperatures and the content of retained austenite. The new steel comprises, by weight, about 0.3-0.45% of C; at most 2.5% of Cr; at most 1.0% of Mo; at most 3.50% of Ni; about 0.3 to 1.5% of Mn; about 0.1-1.3% of Si; about 0.1-1.0% of Cu; Cu being less than Si; about 0.1 to 1.0% of V+Ti+Nb; at most 0.25% of Al; the sum of alloying elements being less than about 11.5%; the balance being essentially Fe and incidental impurities. Procedures of melting, processing and heat treatment using the mathematical model are disclosed.Type: GrantFiled: May 11, 2009Date of Patent: March 20, 2012Inventors: Vladimir A. Fedchun, Gregory Vartanov
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Patent number: 7806998Abstract: A super formable high strength thin steel sheet suitable for use in various applications, e.g., automobiles, and a method for manufacturing the thin steel sheet. The thin steel sheet has a composition which comprises 0.010 wt % or less of C, 0.02 wt % or less of Si, 1.5 wt % or less of Mn, 0.03-0.15 wt % or less of P, 0.02 wt % or less of S, 0.03-0.40 wt % of Sol. Al, 0.004 wt % or less of N, 0.005-0.040 wt % of Ti, 0.002-0.020 wt % of Nb, one or both of 0.001-0.02 wt % of B and 0.005-0.02 wt % of Mo, and the balance of Fe and inevitable impurities, wherein the components P, Mn, Ti, Nb and B satisfy the relationship represented by the following Formulae 1-1 and 1-2, depending on a desired tensile strength: Formula 1-1—tensile strength: 35 kg and 40 kg grades 29.1+89.4P(%)+3.9Mn(%)?133.8Ti(%)+157.5Nb(%)+0.18[B(ppm) or Mo(%)] 15=3544.9 Formula 1-2—tensile strength: 45 kg grade 29.1+98.3P(%)+4.6 Mn(%)86.5Ti(%)62.5Nb(%)+0.Type: GrantFiled: January 18, 2008Date of Patent: October 5, 2010Assignee: PoscoInventors: Hee-Jae Kang, Sang-Ho Han
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Publication number: 20100132848Abstract: The ultrahigh-strength steel sheet contains, in mass %, C: 0.05-0.25%, Si: 1.00-2.5%, Mn: 2.0-4.0%, P: 0.1% or below (not inclusive of 0%), S: 0.05% or below (not inclusive of 0%), Al: 0.01-0.15%, Ti: 0.003-0.10%, N: 0.01% or below (not inclusive of 0%), the balance comprising iron with inevitable impurities, and is a composite structure steel sheet comprising 10-50 area % ferrite and 50 area % or above martensite, in which the average circle-equivalent grain diameter of ferrite grains is 2.0 ?m or below, the average aspect ratio of ferrite grains is 2.0 or below, and the tensile strength is 1,100 MPa or above. Accordingly, the ultrahigh-strength steel sheet is excellent in hydrogen embrittlement resistance and workability.Type: ApplicationFiled: November 2, 2009Publication date: June 3, 2010Applicant: Kabushiki Kaisha Kobe Seiko Sho (Kobe Steel Ltd)Inventors: Muneaki Ikeda, Yukihiro Utsumi
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Publication number: 20090095381Abstract: A high tensile steel sheet having 980 MPa or higher tensile strength with excellent elongation and stretch-flange formability, suitable for the press-forming of complex cross sectional shape such as automobile parts, is manufactured by adjusting the steel to consist essential of a ferrite single phase structure, to precipitate carbide containing Ti, Mo, and V, of smaller than 10 nm of average particle size, in dispersed state, and to have an average composition of the carbide containing Ti, Mo, and V satisfying [V/(Ti+Mo+V)?0.3 (atomic ratio].Type: ApplicationFiled: August 3, 2006Publication date: April 16, 2009Applicant: JFE STEEL CORPORATIONInventors: Tamako Ariga, Takeshi Yokota, Akio Kobayashi, Kazuhiro Seto
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Publication number: 20090038717Abstract: A Ni—Fe—Cr alloy having high strength, ductility and corrosion resistance especially for use in deep-drilled, corrosive oil and gas well environments, as well as for marine environments. The alloy comprises in weight %: 35-55% Ni, 12-25% Cr, 0.5-5% Mo, up to 3% Cu, 2.1-4.5% Nb, 0.5-3% Ti, up to 0.7% Al, 0.005-0.04% C, balance Fe plus incidental impurities and deoxidizers. The alloy must also satisfy the ratio of (Nb?7.75 C)/(Al+Ti)=0.5-9 in order to obtain the desired high strength by the formation of ?? and ?? phases. The alloy has a minimum of 1% by weight ?? phase dispersed in its matrix for strength purposes and a total weight percent of ??+?? phases being between 10 and 30.Type: ApplicationFiled: July 21, 2008Publication date: February 12, 2009Applicant: HUNTINGTON ALLOYS CORPORATIONInventors: Sarwan K. Mannan, Brett Clark Puckett
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Publication number: 20080210346Abstract: A super formable high strength thin steel sheet suitable for use in various applications, e.g., automobiles, and a method for manufacturing the thin steel sheet. The thin steel sheet has a composition which comprises 0.010 wt % or less of C, 0.02 wt % or less of Si, 1.5 wt % or less of Mn, 0.03-0.15 wt % or less of P, 0.02 wt % or less of S, 0.03-0.40 wt % of Sol. Al, 0.004 wt % or less of N, 0.005-0.040 wt % of Ti, 0.002-0.020 wt % of Nb, one or both of 0.001-0.02 wt % of B and 0.005-0.02 wt % of Mo, and the balance of Fe and inevitable impurities, wherein the components P, Mn, Ti, Nb and B satisfy the relationship represented by the following Formulae 1-1 and 1-2, depending on a desired tensile strength: Formula 1-1—tensile strength: 35 kg and 40 kg grades 29.1+89.4P(%)+3.9Mn(%)?133.8Ti(%)+157.5Nb(%)+0.18[B(ppm) or Mo(%)] 15=3544.9 Formula 1-2—tensile strength: 45 kg grade 29.1+98.3P(%)+4.6Mn(%)86.5Ti(%)62.5Nb(%)+0.Type: ApplicationFiled: January 18, 2008Publication date: September 4, 2008Applicant: POSCOInventors: Hee-Jae Kang, Sang-Ho Han
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Publication number: 20070251607Abstract: The present invention concerns processes to break up a structure made of metallic parts covered by asbestos. The process according to the present invention is essentially characterized by the fact that its implementation involves the following successive steps: cutting up of the structure by a laser beam or oxyacetylene torch to obtain fragments, coating of the cut fragments, and melting of the coated fragments in a closed furnace. Its application is especially for the destruction of asbestos covered metallic parts of large volume structures such as ships.Type: ApplicationFiled: April 27, 2007Publication date: November 1, 2007Inventor: Maurice Roulot
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Patent number: 6273971Abstract: The present invention provides a method of manufacturing a cold rolled steel sheet and a hot-dip zinc-coated steel sheet having excellent surface properties, an excellent resistance to natural aging and an excellent dent resistance of panel and, thus, adapted to the manufacture of steel sheet for outer panels of vehicles. The method comprises the steps of preparing steel consisting of 0.005 to 0.012% by weight of C, 0.01 to 0.4% by weight of Si, 0.15 to 1.0% by weight of Mn, 0.01 to 0.08% by weight of P, at most 0.02% by weight of S, 0.01 to 0.1% by weight of sol. Al, at most 0.004% by weight of N, and at least one element selected from the group consisting of 0.01 to 0.2% by weight of Nb and 0.04 to 0.1% by weight of Ti, and satisfying the condition 1.2≦(12/93) (Nb%/C%)+(12/48) (Ti*%/C%)≦2.5, applying a hot rolling and a cold rolling to the steel, soaking the cold rolled steel sheet at T(° C.) meeting a formula Ac3≧T(° C.Type: GrantFiled: April 10, 2000Date of Patent: August 14, 2001Assignee: NKK CorporationInventors: Fusato Kitano, Takeshi Fujita, Tadashi Inoue, Michihiro Hiasa, Takeo Ishii
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Patent number: 5421920Abstract: After a predeoxidation treatment of a molten steel comprising as basic ingredients, in terms of % by weight, 0.04 to 0.20% of C, 0.05 to 0.50% of Si, 0.4 to 2.0% of Mn, 0.3 to 0.7% of Mo, 0.003 to 0.015% of N, 0.04 to 0.20% of V and less than 0.005% of Al to regulate [O %] to 0.003 to 0.015% by weight, titanium is added thereto so as to satisfy a requirement represented by the formula: -0.006.ltoreq.[Ti %]-2[O %].ltoreq.0.008 to crystallize a titanium-based oxide in an amount of 20 particles/mm.sup.2 or more, and MnS, TiN and V(C, N) are deposited on the titanium-based oxide to disperse the titanium-based oxide as a composite precipitate in the steel to provide a cast slab, and a high-strength high-toughness shape steel having an excellent fire resistance is provided by a combination of water cooling between rolling passes at the time of rolling with accelerated cooling after the completion of the rolling.Type: GrantFiled: September 20, 1993Date of Patent: June 6, 1995Assignee: Nippon Steel CorporationInventors: Kohichi Yamamoto, Suguru Yoshida, Kazuo Watanabe
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Patent number: 5205877Abstract: Making wire screens using high carbon steel wire. A first array of wires are placed in a longitudinal configuration and a second array of wires are placed transversely of said first array. The junctions where the wires meet are heated to a temperature of from about 700.degree. F. to about 1000.degree. F. for a time sufficient to disperse heat to adjacent wire areas but insufficient to cause wire fusion. A current is then applied to these junctions sufficient to cause fusion or welding of the junctions. Subsequently, a post weld heat of at least 1575.degree. F. is applied to the wires sufficient to form pearlite in substantial amounts.Type: GrantFiled: March 28, 1991Date of Patent: April 27, 1993Assignee: Bison Steel, Inc.Inventors: John D. Collier, James W. Scheeler