With Tempering, Ageing, Solution Treating (i.e., For Hardening), Precipitation Hardening Or Strengthening, Or Quenching Patents (Class 148/547)
  • Publication number: 20080308195
    Abstract: A spring steel with high fatigue resistance in air and in corrosive conditions and with high resistance to cyclic sag, having the composition in weight percent: C=0.45-0.70% Si=1.65-2.50% Mn=0.20-0.75% Cr=0.60-2% Ni=0.15-1% Mo=traces-1% V=0.003-0.8% Cu=0.10-1% Ti=0.020-0.2% Nb=traces-0.2% AI=0.002-0.050% P=traces-0.015% S=traces-0.015% O=traces-0.0020% N=0.0020-0.0110% the balance being iron, and impurities resulting from the steel making process, where the carbon equivalent Ceq content calculated according to the formula: Ceq %=[C %]+0.12 [Si %]+0.17 [Mn %]?0.1 [Ni %]+0.13 [Cr %]?0.24 [V %] is between 0.80 and 1.00%, and whose hardness, after quenching and tempering, is greater than or equal to 55 HRC.
    Type: Application
    Filed: December 11, 2006
    Publication date: December 18, 2008
    Applicants: Kabushiki Kaisha Kobe Seiko Sho (Kobe Steel, Ltd.), ASCOMETAL
    Inventors: Nao Yoshihara, Kazuhisa Kawata, Julie Mougin, Jacques Languillaume
  • Patent number: 7462251
    Abstract: The invention concerns a method for making an abrasion-resistant steel part consisting of 0.1%?C?0.23%; 0%?Si?2%; 0%?AI?2%; 0.5%?Si+AI?2%; 0%?Mn?2.5%; 0%?Ni?5%; 0%?Cr?5%; 0%?Mo?1%; 0%?W?2%; 0.05%?Mo+W/2?1%; 0%?B?0.02%; 0%?Ti?0.67%; 0%?Zr?1.34%; 0.05%?Ti+Zr/2?0.67%; 0%?S?0.15%; N<0.030, optionally 0% to 1.5% of Cu; optionally Nb, Ta and V such that Nb/2+Ta/4+V?0.5 %; optionally Se, Te, Ca, Bi, Pb contents ?0.1%; the rest being iron and impurities. Additionally: 0.095%?C*=C?Ti/4?Zr/8+7×N/8, Ti+Zr/2?7×N/2?0.05% and 1.05×Mn+0.54×Ni+0.5O×Cr+0.3×(Mo++W1/2)1/2+K>1.8, with K=1 if B?0.0005% and K=0 if B<0.0005%. After austenitization, the method consists in: cooling at a speed >0.5° C./s between AC3 and T=800?270×C*?90×Mn?37×Ni?70×Cr?83×(Mo+W/2) and about T?50° C.; then cooling at a speed 0.1<Vr<150×ep?1.7 between T and 100° C., (ep=thickness of plate in mm); cooling down to room temperature and optionally planishing. The invention also concerns the resulting plate.
    Type: Grant
    Filed: November 13, 2003
    Date of Patent: December 9, 2008
    Assignee: USINOR
    Inventors: Jean Beguinot, Jean-Georges Brisson
  • Patent number: 7459041
    Abstract: The invention concerns a method for making an abrasion resistant steel plate having a chemical composition comprising: 0.35%?C?0.8%, 0%?Si?2%; 0%?AI?2%; 0.35%?Si+AI?2%; 0%?Mn?2.5%; 0%?Ni?5%; 0% ?Cr?5%; 0%?Mo?0.050; 0%?W?1%; 0,1%?Mo+W/2?0.5%; 0%?B?0.02%; 0%?Ti?2%; 0%?Zr?4%; 0.05%?Ti+Zr/2?2%; 0%?S?0.15%; N?0,03; optionally 0% to 1.5% of Cu; optionally Nb, Ta or V with Nb/2+Ta/4 +V?0.5%; optionally less than 0.1% of Se, Te, Ca, Bi or Pb; the rest being iron and impurities; the composition satisfying: 0.1 %<C*=C?Ti/4?Zr/8+7×N/8?0.55% and 1.05×Mn+0.54×Ni+0.5O×Cr+0.3×(Mo+W/2)1/2+K>1.8, with K=0.5 if B ?0.0005% and K=0 if B<0.0005% and Ti+Zr/2?7×N/2?0.05%; hardening after austenitization while cooling at a speed >0.5 ° C./s between a temperature >AC3 and ranging between T=800?270×C*?9O×Mn?37×Ni?70×Cr?83×(Mo+W/2) and T?50° C.; then at a core speed Vr<1150×ep?1.7 between T and 100° C., (ep=plate thickness in mm); cooling down to room temperature. The invention also concerns the resulting plate.
    Type: Grant
    Filed: November 13, 2003
    Date of Patent: December 2, 2008
    Assignee: Industeel Creusot
    Inventors: Jean Beguinot, Jean-Georges Brisson
  • Publication number: 20080283158
    Abstract: The present invention provides a method for manufacturing high tensile strength steel plate having 570 MPa (N/mm2) or larger tensile strength and having also extremely superior balance of strength and toughness both before PWHT and after PWHT to that of the conventional steel plates, by specifically specifying the temperature-rising rate at the plate thickness center portion of a quenched and tempered material during tempering, and to be concrete, the method has the steps of: casting a steel consisting essentially of 0.02 to 0.18% C, 0.05 to 0.5% Si, 0.5 to 2.0% Mn, 0.005 to 0.1% Al, 0.0005 to 0.008% N, 0.03% or less P, 0.
    Type: Application
    Filed: July 6, 2005
    Publication date: November 20, 2008
    Inventors: Akihide Nagao, Kenji Oi
  • Patent number: 7445750
    Abstract: The invention relates to a tool steel, the composition of which comprises (the percentages being expressed in % by weight): 0.8 ? C ? 1.5 5.0 ? Cr ? 14 0.2 ? Mn ? 3 Ni ? 5 V ? 1 Nb ? 0.1 Si + Al ? 2 Cu ? 1 S ? 0.3 Ca ? 0.1 Se ? 0.1 Te ? 0.1 1.0 ? Mo + ½W ? 4 0.06 ? Ti + ½Zr ? 0.15 0.004 ? N ? 0.02 the balance of the composition consisting of iron and impurities resulting from the smelting, it being furthermore understood that: 2.5×10?4%2?(Ti+½Zr)×N, to a process for manufacturing parts made in this steel and to the parts obtained.
    Type: Grant
    Filed: April 16, 2002
    Date of Patent: November 4, 2008
    Assignee: USINOR
    Inventors: Jean Beguinot, Dominique Viale
  • Publication number: 20080236707
    Abstract: A device and method for producing, by molding, a circular-shaped mechanical part made of a metal alloy. The device has a rotatable hollow mold for receiving a predetermined quantity of the metal alloy. The predetermined quantity of the metal alloy is defined by at least one segment of a metal alloy rod. An inductive heating device melts the metal alloy to a melting point. A blank of the mechanical part being formed by centrifuging the melted metal alloy. Cooling the blank in the hollow mold to a second temperature which corresponds to a desired malleability. Processing the blank with a shaping tool to obtain a desired internal profile. To harden and form the circular-shaped mechanical part, the blank is further cooled to a tempering temperature.
    Type: Application
    Filed: September 2, 2005
    Publication date: October 2, 2008
    Inventor: Gianfranco Passoni
  • Patent number: 7425240
    Abstract: The invention relates to a method for producing a siderurgical product made of carbon steel having a high copper content, according to which: —a liquid steel having the composition: 0.0005%?1%; 0.5?Cu?10%; 0?Mn?2%; 0?Si?5% 0?Ti?0.5%; 0?Nb?0.5%; 0?Ni?5%; 0?Al?2%, the remainder being iron and impurities, is produced;—said liquid steel is poured directly in the form of a thin strip having a thickness of no more than 10 mm;—the strip is subjected to forced cooling and/or is surrounded by a non-oxidizing atmosphere while having a temperature of more than 1000? C.; —said thin strip is hot rolled at a reduction rate of at least 10%, the temperature at the end of the rolling process being such that all of the copper is still in a solid solution in the ferrite and/or austenite matrix;—and the strip is coiled. The invention also relates to a siderurgical product obtained according to said method.
    Type: Grant
    Filed: January 13, 2003
    Date of Patent: September 16, 2008
    Assignee: Usinor
    Inventors: Nicolas Guelton, Michel Faral, Jean-Pierre Birat, Catherine Juckum
  • Publication number: 20080178969
    Abstract: Provided is a steel alloy and process for manufacture thereof. The steel alloy has improved ductility, weldability and dimensional stability. Also provided is a manufacturing mold having a manifold that may be formed of the steel alloy. The manifold may include sprues or runners such that the manifold may be used in plastic injection mold. The steel alloy has the chemical composition comprised of (by weight percent) about 0.16-0.2 carbon, about 0.6-0.9 manganese, up to about 0.02 phosphorous, up to about 0.02 sulfur, about 0.25-0.45 silicon, about 2.3-2.7 chromium, up to about 0.2 nickel, up to about 0.15 copper, up to about 0.15 molybdenum, about 0.15-0.03 aluminum and the balance being iron with trace amounts of ordinarily present elements. The steel alloy is electric furnace melted, ladle refined, vacuum degassed and argon shield poured in order to ensure cleanliness and quality.
    Type: Application
    Filed: October 9, 2007
    Publication date: July 31, 2008
    Applicant: Edro Specialty Steels, Inc.
    Inventors: Eric D. Henn, Robert J. Friedrich, Michael A. Guscott, Terry O. Henn
  • Patent number: 7396423
    Abstract: A welding structural steel product exhibiting a superior heat affected zone toughness, comprising, in terms of percent by weight, 0.03 to 0.17% C, 0.01 to 0.5% Si, 0.4 to 2.0% Mn, 0.005 to 0.2% Ti, 0.0005 to 0.1% Al, 0.008 to 0.030% N, 0.0003 to 0.01% B, 0.001 to 0.2% W, at most 0.03% P, at most 0.03% S, at most 0.005% O, and balance Fe and incidental impurities while satisfying conditions of 1.2?Ti/N?2.5, 10?N/B?40, 2.5?Al/N?7, and 6.5?(Ti+2Al+4B)/N?14, and having a microstructure essentially consisting of a complex structure of ferrite and pearlite having a grain size of 20 ?m or less. The method includes the steps of preparing a slab of the above-described composition, heating the slab to 1,100° C. to 1,250° C. for 60-180 minutes, hot rolling the heated slab in an austenite recrystallization range at a 40% or more rolling reduction followed by controlled cooling.
    Type: Grant
    Filed: April 14, 2005
    Date of Patent: July 8, 2008
    Assignee: POSCO
    Inventors: Hong-Chul Jeong, Hae-Chang Choi
  • Patent number: 7323070
    Abstract: A process of producing a maraging steel includes melting a steel of a defined composition, casting the molten steel to obtain a steel ingot, hot forging the steel ingot at a forging ratio of at least 4, then soaking the forged piece one or more times to keep the forged piece in a temperature range of 1100-1280° C. for 10-100 hours, and then plastic working the forged piece. A process of producing a maraging steel of another defined composition includes casting the molten steel to obtain a steel ingot with a defined taper, a defined height to diameter ratio and a defined flatness ratio and plastic working the steel ingot so that the size of a nonmetallic inclusion is 30 ?m or less expressed as the diameter of a circle of circumference equal to the perimeter (“circumference”) of the inclusion.
    Type: Grant
    Filed: March 26, 2004
    Date of Patent: January 29, 2008
    Assignee: Neomax Materials Co., Ltd.
    Inventors: Masami Ueda, Kenji Hirano
  • Patent number: 7288158
    Abstract: A flat rolled, high strength, formable steel product has a yield strength of at least about 100 ksi. The product has sufficient formability such that it can withstand a longitudinal or transverse 180° bend of less than 1.0 times its thickness and is preferably comprised of a high strength, low alloy steel composition containing a vanadium-nitride microalloy. The steel product is preferably produced by cold rolling a first steel product having a yield strength of at least about 70 ksi and a n-value from about 0.1 to about 0.16. Cold rolling of the first steel product reduces its thickness and increases its yield strength to at least 100 ksi.
    Type: Grant
    Filed: March 9, 2005
    Date of Patent: October 30, 2007
    Assignee: Algoma Steel Inc.
    Inventors: Barton A. Thomson, James W. Johnston
  • Patent number: 7005017
    Abstract: The invention relates to a steel for mechanical construction, wherein its composition in percentages by weight is: 0.35%?C?1.2%; 0.10%?Mn?2.0%; 0.10%?Si?3.0%; traces?Cr?4.5%; traces?Mo?2.0%; traces?Ni?4.5%; traces?V?0.5%; traces?Cu?3.5% with Cu?Ni %+0.6 Si % if Cu?0.5%; traces?P?0.200%, traces?Bi?0.200%, traces?Sn?0.150%, traces?As?0.100%, traces?Sb?0.150%, with 0.050%?P %+Bi %+Sn %+As %+Sb %?0.200%, traces?Al?0.060%; traces?Ca ?0.050%; traces?B?0.01%; traces?S?0.200%; traces?Te?0.020%; traces?Se?0.040%; traces?Pb?0.070%; traces?Nb?0.050%; traces?Ti?0.050%; the remainder being iron and impurities resulting from the manufacture.
    Type: Grant
    Filed: December 3, 2003
    Date of Patent: February 28, 2006
    Assignee: ASCOMETAL
    Inventor: Marc Robelet
  • Patent number: 6994758
    Abstract: The invention relates to a steel for mechanical construction, wherein its composition in percentages by weight is: 0.35%?C?2.5%; 0.10%?Mn?2.5%; 0.60%?Si?3.0%; traces?Cr?4.5%; traces?Mo?2.0%; traces?Ni?4.5%; traces?V?0.5%; traces?Cu?4% with Cu?Ni %+0.6 Si % if Cu?0.5%; traces?Al?0.060%; traces?Ca?0.050%; traces?B?0.01%; traces?S?0.200%; traces?Te?0.020%; traces?Se?0.040%; traces?Pb?0.070%; traces?Nb?0.050%; traces?Ti?0.050%; the remainder being iron and impurities resulting from the manufacture. The invention also relates to a method of hot-shaping a steel part, wherein a billet of steel of the preceding composition is obtained, it is heated to a temperature between the solidus and the liquidus so as to obtain a liquid phase and a globular solid phase, shaping of the said billet is carried out by thixoforging so as to obtain the said part, and cooling of the said part is carried out. Finally, the invention relates to a steel part thus obtained.
    Type: Grant
    Filed: December 3, 2003
    Date of Patent: February 7, 2006
    Assignee: Ascometal
    Inventor: Marc Robelet
  • Patent number: 6971351
    Abstract: A region including an engaging hole is given surface treatment such as partial quench hardening by induction hardening for improving surface hardness of the region. The partial quench hardening by induction hardening provides the region with satisfactory mechanical strength or surface hardness enough for resisting deformation of the engaging hole and wear-out of an edge of opening of the engaging hole caused by putting in and out of the lock pin.
    Type: Grant
    Filed: February 20, 2004
    Date of Patent: December 6, 2005
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Hiroyuki Kinugawa, Makoto Yamauchi
  • Patent number: 6896747
    Abstract: Austenitic alloy for high-temperature strength with improved pourability and manufacturing, of which the composition comprises, in weight-%: 0.010%<carbon<0.04% 0%<nitrogen<0.01% silicon<2% 16%<nickel<19.9% manganese<8% 18.1%<chromium<21% 1.8%<titanium<3% molybdenum<3% copper<3% aluminum<1.5% boron<0.01% vanadium<2% sulfur<0.2% phosphorous<0.04% and possibly up to 0.5% of at least one element chosen from among yttrium, cerium, lanthanum and other rare earths, the remainder being iron and impurities resulting from manufacturing or deoxidizing, the said composition also satisfying the two following relationships: in relationship to the solidification mode: remainder a=eq. Nia?0.5×eq. Cra<3.60 where eq. Cra=Cr+0.7×Si+0.2×Mn+1.37×Mo+3×Ti+6×Al+4×V, and where eq. Nia=Ni+22×C+0.5×Cu, in relationship to the rate of residual ferrite: remainder b=eq. Nib?2×eq. Crb>?41 where eq. Crb=Cr+0.7×Si+1.37×Mo+3×Ti+6×Al+4×V, and where eq. Nib=Ni+22×C+0.5×Cu+0.
    Type: Grant
    Filed: November 1, 2002
    Date of Patent: May 24, 2005
    Assignee: Usinor
    Inventors: Jean-Michel Hauser, Christophe Bourgin
  • Patent number: 6863749
    Abstract: A method of post-solidification processing to minimize the content of extremely coarse grain-refining precipitates that may form during solidification is low-alloy and alloy high-strength steels containing approximately 0.09-0.17% by weight C so as to provide improved toughness in a wrought and heat-treated product. The method entails cooling an as-cast steel at a reduced rate in a furnace held at a temperature in excess of the equilibrium solution temperature for AlN in austenite. The steel is maintained at this temperature for a sufficient amount of time to effect the dissolution of coarse AlN precipitates in the microstructure, and the so-treated steel is then cooled at any desired rate to room temperature or to a hot-rolling temperature.
    Type: Grant
    Filed: July 26, 2000
    Date of Patent: March 8, 2005
    Assignee: The Timken Company
    Inventor: Michael J. Leap
  • Patent number: 6855213
    Abstract: A ferritic non-ridging stainless steel and process therefor. A chromium alloyed steel melt containing sufficient titanium and nitrogen but a controlled amount of aluminum is cast into an ingot or continuously cast into a strip or a slab having an as-cast fine equiaxed grain structure substantially free of columnar grains. The as-cast steel contains 0.08% C, at least about 8% Cr, up to 1.50% Mn, <0.020% Al, ?0.05% N, ?1.5% Si, <2.0% Ni, Ti?0.10%, the ratio of (Ti×N)/Al?0.14, all percentages by weight, the balance Fe and residual elements. Preferably, the titanium is controlled so that (Ti/48)/[(C/12)+(N/14)]>1.5. A hot processed sheet may be formed from a continuously cast slab without grinding the surfaces of the slab. The hot processed sheet may be descaled, cold reduced to a final thickness and recrystallization annealed. Annealing the hot processed sheet prior to cold reduction is not required to obtain an annealed sheet essentially free of ridging and having high formability.
    Type: Grant
    Filed: September 15, 1998
    Date of Patent: February 15, 2005
    Assignee: Armco Inc.
    Inventors: Eizo Yoshitake, Alan R. McKague
  • Patent number: 6852180
    Abstract: The invention relates to the iron and steel industry. More specifically, the invention describes the manufacture of steel strip intended to be converted into thin packaging, such as for drinks and preserved food.
    Type: Grant
    Filed: September 20, 2000
    Date of Patent: February 8, 2005
    Assignee: Usinor
    Inventors: Michel Faral, Michel Guttmann, Jean-Hubert Schmitt, Catherine Juckum, Helene Regle
  • Patent number: 6835253
    Abstract: The invention relates to a method for producing a hot strip, in particular for producing a hot strip intended for the production of a cold strip with good deep-drawing characteristics; in which a steel melt comprising (in % by weight) C:≦0.07%, Si:≦0.5%, Mn:≦2.5%, Al:≦0.1%, N:≦0.01%, P:≦0.025, B:≦0.05, if need be up to a total of 0.
    Type: Grant
    Filed: July 22, 2002
    Date of Patent: December 28, 2004
    Assignee: Thyssenkrupp Stahl AG
    Inventors: Rudlof Kawalla, Bernhard Engl, Thomas Heller, Wolfgang Rasim, Eberhard Sowka
  • Patent number: 6818079
    Abstract: A method for manufacturing a steel sheet comprising continuously casting a steel containing 0.04 to 0.2 wt. % C, 0.25 to 2 wt. % Si, 0.5 to 2.5 wt. % Mn, and 0.1 wt. % or less Al to form a slab; hot-rolling by rough-rolling the slab to form a sheet bar and finish-rolling the sheet bar with a reduction in thickness at the final stand of less than 30%, the finish-rolling being completed at a temperature from the Ar3 transformation point to the Ar3 transformation point +60° C.; primary-cooling the hot-rolled steel sheet, the primary cooling being started within 1 second after the completion of hot-rolling and conducting the cooling at a cooling speed of higher than 200° C./sec down to a temperature of Ar3 −30° C. to the Ar1 transformation point; slow cooling or air-cooling the primary-cooled steel sheet at a temperature of the Ar3 transformation point to the Ar1 transformation point at 10° C.
    Type: Grant
    Filed: May 27, 2003
    Date of Patent: November 16, 2004
    Assignee: NKK Corporation
    Inventors: Tadashi Inoue, Yoichi Motoyashiki, Hiroyasu Kikuchi, Yoshimasa Funakawa, Hiroshi Nakata, Sadanori Imada, Toru Inazumi
  • Patent number: 6793745
    Abstract: The invention relates to a high-strength, age-hardenable, corrosion-resistant maraging type spring steel, which is essentially comprised of 6.0 to 9.0 wt. % of Ni, 11.0 to 15.0 wt. % of Cr, 0.1 to 0.3 wt. % of Ti, 0.2 to 0.3 wt. % of Be and of a remainder consisting of Fe, whose martensite temperature Ms≧130° C. and which has a ferrite content cferrite of less than 3%.
    Type: Grant
    Filed: September 16, 2002
    Date of Patent: September 21, 2004
    Assignee: Vacuumschmelze GmbH & Co. KG
    Inventors: Hartwin Weber, Waldemar Doering, Gernot Hausch
  • Patent number: 6793744
    Abstract: The present invention relates to a martensitic stainless steel that can be used in manufacturing articles such as a shaft or an impeller which require high mechanical strength and corrosion resistance and provides a martensitic stainless steel comprising less than 0.06 wt. % C, less than 2.5 wt. % Si, less than 2.5 wt. % Mn, 1.0-6.0 wt. % Ni, 10.0-19.0 wt. % Cr, 0.5-6.0 wt. % W, less than 3.5 wt. % Mo, less than 0.5 wt. % Nb, less than 0.5 wt. % V, less than 3.0 wt. % Cu, 0.05-0.25 wt. % N, and the remainder being Fe and minor impurities.
    Type: Grant
    Filed: November 15, 2000
    Date of Patent: September 21, 2004
    Assignee: Research Institute of Industrial Science & Technology
    Inventor: Jae-Young Jung
  • Publication number: 20040108020
    Abstract: The invention provides a method of fabricating a steel part, the method comprising the steps of:
    Type: Application
    Filed: December 2, 2003
    Publication date: June 10, 2004
    Inventors: Pierre Dierickx, Gaelle Andre
  • Patent number: 6689229
    Abstract: A high strength cold rolled steel sheet consists essentially of 0.0040 to 0.01% C, not more than 0.05% Si, 0.1 to 1.0% Mn, 0.01 to 0.05% P, not more than 0.02% S, 0.01 to 0.1% sol.Al, not more than 0.004% N, 0.01 to 0.14% Nb, by weight, and a balance of substantially Fe and inevitable impurities, and having an n value of not less than 0.21 calculated from two points (1% and 10%) of nominal strain determined by the uniaxial tensile test, and a method for manufacturing the cold rolled steel sheet. The high strength cold rolled steel sheet has excellent combined formability, resistance to embrittlement during secondary operation, formability at welded portions, and anti-burring performance, and has a desirable surface appearance and uniformity of material in a coil, and thus can be desirably used for automobile exterior panels.
    Type: Grant
    Filed: April 15, 2002
    Date of Patent: February 10, 2004
    Assignee: NKK Corporation
    Inventors: Takeshi Fujita, Fusato Kitano, Yoshihiro Hosoya, Toru Inazumi, Yuji Yamasaki, Masaya Morita, Yasunobu Nagataki, Kohei Hasegawa, Hiroshi Matsuda, Moriaki Ono
  • Patent number: 6669789
    Abstract: A composition and method of making a high-strength low-alloy hot-rolled steel sheet, strip, or plate bearing titanium as the principal or only microalloy strengthening element. The steel is substantially ferritic and has a microstructure that is at least 20% acicular ferrite. The steel has a minimum yield strength of at least 345 MPa (50 ksi) and even over 621 MPa (90 ksi) adding titanium as the lone microalloy element for strengthening, with elongation of 15% and more. Addition of vanadium, niobium, or a combination thereof can result in yield strengths exceeding 621 MPa (90 ksi). Effective titanium content, being the content of titanium in the steel not in the form of nitrides, oxides, or sulfides, is in the range of 0.01 to 0.12% by weight. The manufacturing process includes continuously casting a thin slab and reducing the slab thickness using thermomechanical controlled processing, including dynamic recrystallization controlled rolling.
    Type: Grant
    Filed: August 31, 2001
    Date of Patent: December 30, 2003
    Assignee: Nucor Corporation
    Inventors: Daniel Geoffrey Edelman, Steven Leonard Wigman
  • Patent number: 6663730
    Abstract: A maraging steel strip or part and process for manufacture of a strip or of a part cut out of a strip of cold-rolled maraging steel and hardened by a hardening heat treatment. In the process, before the hardening heat treatment is performed, the strip or the part is subjected to cold plastic deformation with a degree of working greater than 30% and the strip or the part is subjected to recrystallization annealing in order to obtain a fine-grained structure with ASTM index higher than 8. The composition by weight of the maraging steel is: 12%≦Ni≦24.5%; 2.5%≦Mo≦12%; 4.17%≦Co≦20%, Al %≦0.15%; Ti≦0.1%; N≦0.003%; Si≦0.1%; Mn≦0.1%; C≦0.005%; S≦0.001%; P≦0.005%; H≦0.0003%; O≦0.001%; iron and impurities resulting from smelting, the chemical composition also satisfying the relationships: 20%≦Ni+Mo≦27%; 50≦Co×Mo≦200; Ti×N≦2×10−4.
    Type: Grant
    Filed: November 19, 2001
    Date of Patent: December 16, 2003
    Assignee: Imphy Ugine Precision
    Inventor: Lucien Coutu
  • Patent number: 6663725
    Abstract: The present invention relates to a high strength steel sheet consisting essentially of 0.04 to 0.1% C, 0.5% or less Si, 0.5 to 2% Mn, 0.05% or less P, 0.005% or less 0, 0.005% or less S, by weight, having 10 &mgr;m or less of average ferritic grain size, and 20 mm/mm2 or less of generation frequency A, which generation frequency A is defined as the total length of a banded secondary phase structure observed per 1 mm2 of steel sheet cross section along the rolling direction thereof. The steel sheet is manufactured by, for example, a method comprising the steps of: hot-rolling a continuously cast slab having the composition described above at temperatures of Ar3 transformation point or above directly or after reheating thereof; and cooling the hot-rolled steel sheet within 2 seconds down to the temperatures of from 600 to 750° C. at cooling speeds of from 100 to 2,000° C./sec, followed by coiling the cooled steel sheet at temperatures of from 450 to 650° C.
    Type: Grant
    Filed: April 5, 2001
    Date of Patent: December 16, 2003
    Assignee: NKK Corporation
    Inventors: Tadashi Inoue, Hiroyasu Kikuchi, Sadanori Imada, Takayuki Odake
  • Patent number: 6652670
    Abstract: The method for manufacturing steel sheet comprises the steps of: rough-rolling to form a sheet bar; finish-rolling the sheet bar to form a steel strip; applying primary cooling and secondary cooling to the finish-rolled steel strip; and coiling the secondary-cooled steel strip. The primary cooling is conducted at cooling speeds of 120° C./sec or more down to the temperatures of from 500 to 800° C. The secondary cooling is conducted at cooling speeds of less than 60° C./sec.
    Type: Grant
    Filed: April 18, 2001
    Date of Patent: November 25, 2003
    Inventors: Tadashi Inoue, Yoichi Motoyashiki, Hiroyasu Kikuchi, Yasuhide Ishiguro, Sadanori Imada, Toru Inazumi
  • Patent number: 6648991
    Abstract: Low-alloy carbon steel for the manufacture of seamless pipes having improved resistance to corrosion, particularly the “sweet corrosion” that occurs in the media rich in CO2, for using in exploration and production of oil and/or natural gas. The steel contains: 1.5-4.0% by weight of Cr, 0.06-0.10% by weight of C, 0.3-0.8% by weight of Mn, not more than 0.005% by weight of S, not more than 0.015% by weight of P, 0.20-0.35% by weight of Si, 0.25-0.35% by weight of Mo, 0.06-0.9% by weight of V, approximately 0.22% by weight of Cu, approximately 0.001% by weight of Nb, approximately 0.028% by weight of Ti, not more than a total value of O of 25 ppm, with the balance being Fe and unavoidable impurities.
    Type: Grant
    Filed: March 13, 2002
    Date of Patent: November 18, 2003
    Assignee: Siderca S.A.I.C.
    Inventors: Gustavo Javier López Turconi, Teresa Estela Pérez, Juan Carlos González
  • Patent number: 6641681
    Abstract: The invention concerns a steel material which consists of a steel having the following chemical composition in weigh-%: 1.0-1.9 C, 0.5-2.0 Si, 0.1-1.5 Mn, 4.0-5.5 Cr, 2.5-4.0 (Mo+W/2), however max 1.0 W, 2.0-4.5 (V+Nb/2), however max 1.0. Nb, balance iron and impurities in normal amounts in the form of residual elements from the manufacturing of the steel, and with a microstructure, which in the hardened and tempered condition of the steel contains 5-12 vol-% MC-carbides, at least about 80 vol-% of the carbides having a size which is larger than 3 &mgr;m but smaller than 25 &mgr;m preferably smaller than 20 &mgr;m, and, prior to tempering, 0.50-0.70 weight-% carbon, which is dissolved in the martensite in the hardened condition of the steel. The material is intended for cold work tools, in the first place for homogenous rolls for cold rolling of meta, strips.
    Type: Grant
    Filed: February 12, 2002
    Date of Patent: November 4, 2003
    Assignee: Uddeholm Tooling Aktiebolag
    Inventors: Odd Sandberg, Bo Rydell
  • Patent number: 6623573
    Abstract: The method for manufacturing steel sheet comprises the steps of: forming a sheet bar; forming a steel strip; primary-cooling; air-cooling; secondary-cooling; and coiling. The sheet bar is finish-rolled at finish temperatures of (Ar3 transformation point −20° C.) or more. The primary cooling cools the finish-rolled steel strip at cooling speeds of more than 120° C./sec down to the temperatures ranging from 500 to 800° C.
    Type: Grant
    Filed: April 19, 2001
    Date of Patent: September 23, 2003
    Assignee: NKK Corporation
    Inventors: Tadashi Inoue, Yoichi Motoyashiki, Hiroyasu Kikuchi, Sadanori Imada
  • Patent number: 6579385
    Abstract: Free machining steel for use in machine structures capable of stably and reliably providing excellent machinability (chip disposability and tool life) and mechanical characteristics (transverse direction toughness) comparable, in a Pb free state, with existent Pb-added steels the machining steel being manufactured so as to contain 0.0005 to 0.02 mass % of Mg and provide a distribution index F1 for the sulfide particles defined by the following equation (1) of 0.4 to 0.65 or a distribution index for the sulfide particles defined by the following equation (2) of 1 to 2.5: F1=X1/(A/n)½  (1), or F2=&sgr;F/X2  (2) as described in the specification.
    Type: Grant
    Filed: August 17, 2001
    Date of Patent: June 17, 2003
    Assignee: Kabushiki Kaisha Kobe Seiko Sho (Kobe Steel, Ltd.)
    Inventors: Hiroshi Yaguchi, Yosuke Shindo, Takehiro Tsuchida, Takahiro Kudou, Masato Kaiso, Masami Somekawa
  • Patent number: 6557622
    Abstract: Surface defects in rolled steel are remedied by quenching a surface layer of the steel product downstream of the caster and upstream of the reheat furnace by transversely differentiated quenching to match the transverse temperature profile of the steel product. The flow rate of the quench spray is differentially adjustable across the width and optionally the length of the steel product. An array of spray nozzles controlled in transversely or longitudinally arranged groups provides the quench spray.
    Type: Grant
    Filed: February 19, 2002
    Date of Patent: May 6, 2003
    Assignee: IPSCO Enterprises Inc.
    Inventors: William R. Frank, Jonathan Dorricott, Laurie E. Collins, Joseph D. Russo, Robert J. Boecker, Brian H. Wales
  • Patent number: 6558486
    Abstract: Method of producing strip comprising continuously casting plain carbon steel into a strip of no more than 5 mm thickness and coiling the strip. The strip is subsequently uncoiled and cold rolled then annealed to produce a stress relieved microstructure therein. The cold rolling produces a cold reduction sufficient to increase the tensile strength of the strip to at least 680 MPa but is such that the total elongation to break off the strip after the annealing is in the range 8% to 12%. The cold rolling may produce a cold reduction of the strip thickness in the range 40% to 80%. The continuously cast strip may be optionally in-line hot rolled prior to coiling to produce an initial strip thickness in the range 40% to 60%.
    Type: Grant
    Filed: August 31, 2001
    Date of Patent: May 6, 2003
    Assignee: Castrip, LLC
    Inventors: Lazar Strezov, Kannappar Mukunthan
  • Patent number: 6524408
    Abstract: To produce sheet steel components optimised for loading, a steel strip is cast between two cooled rolls with a variable nip and the thickness of the steel strip is changed by changing the time of contact between the strand shells and the rolls or by changing the cooling intensity of the rolls on the molten steel cast into the gusset formed by the rolls, thereby changing the thickness of the steel strip. Such a strip has a homogeneous structure and can subsequently be given a special quality by hot or cold rolling for its particular purpose of use.
    Type: Grant
    Filed: June 18, 2001
    Date of Patent: February 25, 2003
    Assignee: Thyssen Krupp Stahl AG
    Inventors: Wilhelm Schmitz, Dieter Senk, Ulrich Albrecht-Früh, Reiner Kopp
  • Patent number: 6517955
    Abstract: The invention relates to a high strength hot-dip galvanized and galvannealed steel sheets with excellent drawability for press forming and excellent plating adhesion that is useful as a member for automobiles, construction, electric devices and the like, and to a process for its manufacture. According to an embodiment of the invention, the steel sheet contains in terms of weight percent, C: 0.05-0.2%, Si: 0.2-2.0%, Mn: 0.2-2.5%, Al: 0.01-1.5%, Ni: 0.2-5.0%, P: <0.03% and S: <0.02%, the relationship between Si and Al being such that 0.4(%)≦Si+0.8 Al(%)≦2.0% and the remainder consisting of Fe and unavoidable impurities, the volume percentage of the retained austenite is 2-20% and the steel sheet surface wherein the relationship between the Ni and Si, Al in 0.5 &mgr;m of the steel sheet surface layer is such that Ni(%)≦¼ Si+⅓Al(%), has a Zn plating layer comprising Al: ≦1% with the remainder Zn and unavoidable impurities.
    Type: Grant
    Filed: December 29, 2000
    Date of Patent: February 11, 2003
    Assignee: Nippon Steel Corporation
    Inventors: Yoshihisa Takada, Masayoshi Suehiro
  • Publication number: 20030019746
    Abstract: Sputtering targets and methods of making sputtering targets are described. The method includes the steps of: providing a sputtering metal workpiece made of a valve metal; transverse cold-rolling the sputtering metal workpiece to obtain a rolled workpiece; and cold-working the rolled workpiece to obtain a shaped workpiece. The sputtering targets exhibits a substantially consistent grain structure and/or texture on at least the sidewalls.
    Type: Application
    Filed: November 9, 2001
    Publication date: January 30, 2003
    Inventors: Robert B. Ford, Christopher A. Michaluk
  • Patent number: 6494969
    Abstract: The present invention relates to a very low C—Nb cold rolled steel sheet giving 340 to 440 MPa of tensile strength. For example, the cold rolled steel sheet consists essentially of 0.0040 to 0.01% C, not more than 0.05% Si, 0.1 to 1.0% Mn, 0.01 to 0.05% P, not more than 0.02% S, 0.01 to 0.1% sol.Al, not more than 0.004% N, 0.01 to 0.14% Nb, by weight, and balance of substantially Fe and inevitable impurities, and has not less than 0.21 of n value calculated from two points (1% and 10%) of nominal strain determined by the uniaxial tensile test, and relates to a method for manufacturing the cold rolled steel sheet. The present invention provides a high strength cold rolled steel sheet for automobile exterior panels having excellent combined formability, resistance to embrittlement during secondary operation, formability at welded portions, anti-burring performance, good surface appearance, and uniformity of material in a coil.
    Type: Grant
    Filed: August 3, 2000
    Date of Patent: December 17, 2002
    Assignee: NKK Corporation
    Inventors: Takeshi Fujita, Fusato Kitano, Yoshihiro Hosoya, Toru Inazumi, Yuji Yamasaki, Masaya Morita, Yasunobu Nagataki, Kohei Hasegawa, Hiroshi Matsuda, Moriaki Ono
  • Patent number: 6475307
    Abstract: A composition and method for the manufacture of products of a precipitation hardenable martensitic stainless steel, the composition of which comprises at least 0.5% by weight of Cr and at least 0.5% by weight of Mo wherein the sum of Cr, Ni and Fe exceeds 50%. The method steps include smelting the material into a casting, hot extrusion followed by a number of cold deforming steps so as to obtain at least 50% martensite and finally an ageing treatment at 425-525° C. to obtain precipitation of quasicrystalline particles. Such material can be used in vehicle components where demands for corrosion resistance, high strength and good toughness are to be satisfied.
    Type: Grant
    Filed: November 16, 2000
    Date of Patent: November 5, 2002
    Assignee: Sandvik AB
    Inventors: Anna-Lena Nyström, Anna Hultin Stigenberg
  • Publication number: 20020104597
    Abstract: A steel rolling mill including a Steckel mill is provided with an in-line upstream quench station located downstream of the caster and upstream of the reheat furnace, a shear located downstream of the Steckel mill, and a temperature reduction station downstream of the shear. The upstream quench station has spray nozzles that quench a surface layer of the steel to transform same from an austentitic to a non-austentitic microstructure. The shear provides a precise transverse vertical face on the leading end of the steel. The temperature reduction station applies cooling fluid to the rolled steel so as to obtain a preferred microstructure that may be either bainite or martensite. If bainite, the temperature reduction station includes laminar-flow cooling apparatus; if martensite, the station also includes an initial rapid quench, in which latter case the station is followed by a tempering furnace.
    Type: Application
    Filed: July 19, 2001
    Publication date: August 8, 2002
    Applicant: IPSCO Enterprises Inc.
    Inventors: William R. Frank, Jonathan Dorricott, Laurie E. Collins, Joseph Duane Russo, Robert Joseph Becker, Brian H. Wales
  • Patent number: 6383316
    Abstract: Through electro slag refining of a bloom of a stainless, precipitation hardenable stainless steel of 17-7 PH type, the fatigue resistance of springs made of cold drawn wires of said material is increased substantially. This depends on the fact that large slag inclusions, which can initiate fatigue failures, are eliminated at the ESR remelting, while longer zones containing concentrations of small slag inclusions are substantially reduced. The material is particularly suitable for springs in injection pumps for Diesel engines.
    Type: Grant
    Filed: June 16, 2000
    Date of Patent: May 7, 2002
    Assignee: Haldex Garphyttan Aktiebolag
    Inventor: Claes-Henrik Engström
  • Patent number: 6372063
    Abstract: The process for manufacturing a metallic component, such as a wheel part for the rolling system of a vehicle, which includes, in an initial stage, forming the component of a metallic material in a semi-solid state and having a thixotropic structure, and in a subsequent cold-treatment stage, cold-treating at least part of said component by blasting it with projectiles with a view to plastic deformation thereof. A wheel in which a metallic disk is welded to a wheel rim and in which the metallic disk is obtained by the manufacturing process.
    Type: Grant
    Filed: June 8, 2000
    Date of Patent: April 16, 2002
    Assignee: Michelin Recherche et Technique, S.A.
    Inventor: Gilles Grillon
  • Patent number: 6358338
    Abstract: The invention relates to a process for producing strip made of an iron-carbon-manganese alloy, in which: a thin strip, having a thickness of 1.5 to 10 mm, is cast directly on a casting machine from a liquid metal of composition, in percentages by weight: C ranging between 0.001 and 1.6%; Mn ranging between 6 and 30%; Ni≦10% with (Mn+Ni) ranging between 16 and 30%; Si≦2.5%; Al≦6%; Cr≦10%; (P+Sn+Sb+As)≦0.2%; (S+Se+Te)≦0.5%; (V+Ti+Nb+B+Zr+rare earths)≦3%; (Mo+W)≦0.5%; N≦0.3%; Cu≦5%, the balance being iron and impurities resulting from the smelting; the said strip is cold rolled with a reduction ratio ranging between 10 and 90% in one or more steps; and the said strip undergoes recrystallization annealing. The invention also relates to a strip that can be produced by this process.
    Type: Grant
    Filed: July 7, 2000
    Date of Patent: March 19, 2002
    Assignee: Usinor
    Inventors: Nicolas Guelton, Michel Faral, Odile Faral
  • Patent number: 6319338
    Abstract: The object of the present invention is to provide high-strength steel sheets exhibiting high impact energy absorption properties, as steel materials, to be used for shaping and working into such parts as front side members of automobiles which absorb impact energy upon collision, as well as a method for their production.
    Type: Grant
    Filed: July 6, 1999
    Date of Patent: November 20, 2001
    Assignee: Nippon Steel Corporation
    Inventors: Osamu Kawano, Yuzo Takahashi, Junichi Wakita, Hidesato Mabuchi, Manabu Takahashi, Akihiro Uenishi, Riki Okamoto, Yukihisa Kuriyama, Yasuharu Sakuma
  • Patent number: 6294031
    Abstract: A production method of a heat-treated steel member includes the steps of: shaping a steel material of low-carbon boron steel containing about 0.05-0.30% carbon by weight into a predetermined configuration to bc a shaped material; and heat-treating the shaped material, said heat-treating, includes quench-hardening only.
    Type: Grant
    Filed: September 4, 1998
    Date of Patent: September 25, 2001
    Assignee: Topy Kogyo Kabushiki Kaisha
    Inventors: Hiroyuki Takeno, Masahiro Nakajima, Kiyokazu Niwa, Go Morishima, Daigo Sugiyama
  • Patent number: 6273973
    Abstract: A process for producing a steel includes subjecting at least a portion of a melt of the steel to electroslag remelting and, in a subsequent step, heating the steel to a temperature at least as great as the lowest temperature at which all carbides that can form in the remelted steel will dissolve and no greater than the nil ductility temperature of the of the remelted steel, and maintaining the temperature for a period of time sufficient to dissolve primary and clustered carbide particles in the remelted steel greater than 15 micrometers in length. A novel martensitic stainless steel also is disclosed including 0.65 to 0.70 carbon; 0 to 0.025 phosphorus; 0 to 0.020 sulfur; 0.20 to 0.50 silicon; at least one of greater than 0.0004 boron and greater than 0.03 nitrogen; 0.45 to 0.75 manganese; 12.7 to 13.7 chromium; and 0 to 0.50 nickel.
    Type: Grant
    Filed: December 2, 1999
    Date of Patent: August 14, 2001
    Assignee: ATI Properties, Inc.
    Inventors: Thomas R. Parayil, David S. Bergstrom, Raymond A. Painter
  • Patent number: 6273971
    Abstract: 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: Grant
    Filed: April 10, 2000
    Date of Patent: August 14, 2001
    Assignee: NKK Corporation
    Inventors: Fusato Kitano, Takeshi Fujita, Tadashi Inoue, Michihiro Hiasa, Takeo Ishii
  • Patent number: 6270594
    Abstract: A method of making a high strength low-alloy steel includes the steps of casting an alloy steel into a cast form, hot rolling the cast form into a partially rolled form, and control rolling the partially rolled form to a rolled product. The controlled rolling is discontinued at a discontinue rolling temperature and is then acceleratedly cooled to a finish cooling temperature. The alloy steel uses a low silicon, carbon niobium, vanadium, titanium-containing steel composition. Silicon is less than 0.04% by weight, vanadium is between 0.05 and 0.10% by weight, niobium is between 0.06 and 0.14% by weight, titanium is between 0.006 and 0.02% by weight, and carbon is between 0.06 and 0.14% by weight. The controlled chemistry, controlled rolling, and accelerated cooling allows the discontinue rolling temperature to be high, thereby improving rolling productivity. The low-carbon alloy chemistry results in improvements in castability, formability, and weldability.
    Type: Grant
    Filed: March 4, 1998
    Date of Patent: August 7, 2001
    Assignee: Bethlehem Steel Corporation
    Inventors: Richard L. Bodnar, Yulin Shen
  • Patent number: 6264767
    Abstract: A steel rolling mill including a Steckel mill is provided with an in-line upstream quench station located downstream of the caster and upstream of the reheat furnace, a shear located downstream of the Steckel mill, and a temperature reduction station downstream of the shear. The upstream quench station has spray nozzles that quench a surface layer of the steel to transform same from an austentitic to a non-austentitic microstructure. The shear provides a precise transverse vertical face on the leading end of the steel. The temperature reduction station applies cooling fluid to the rolled steel so as to obtain a preferred microstructure that may be either bainite or martensite. If bainite, the temperature reduction station includes laminar-flow cooling apparatus; if martensite, the station also includes an initial rapid quench, in which latter case the station is followed by a tempering furnace.
    Type: Grant
    Filed: July 9, 1999
    Date of Patent: July 24, 2001
    Assignee: IPSCO Enterprises Inc.
    Inventors: William R. Frank, Jonathan Dorricott, Laurie E. Collins, Joseph Duane Russo, Robert Joseph Boecker, Brian H. Wales
  • Publication number: 20010001438
    Abstract: A high purity cobalt sputter target is disclosed which contains a face centered cubic (fcc) phase and a hexagonal close packed (hcp) phase, wherein the value of the ratio of X-ray diffraction peak intensity, Ifcc(200)/Ihcp(10 {overscore (1)}1), is smaller than the value of the same ratio in a high purity cobalt material obtained by cooling fcc cobalt to room temperature from the high temperature at which it is molten.
    Type: Application
    Filed: August 25, 1998
    Publication date: May 24, 2001
    Applicant: Robert S. Cole et al
    Inventors: ROBERT S. COLE, MATHEW S. COOPER, STEPHEN P. TURNER, YINSHI LIU, MICHAEL MCCARTY, RODNEY L. SCAGLINE