Patents by Inventor Mineo Muraki
Mineo Muraki has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
-
Patent number: 6884388Abstract: A martensitic stainless steel sheet which is hard to be softened by tempering caused by heating during the use of a disk brake, can maintain the predetermined hardness, and has excellent punching workability, bending workability before quenching, and a particularly small shear drop, and in which a predetermined hardness after quenching is constantly achieved, in a low carbon martensitic stainless steel sheet used only after quenching. Specifically, the sheet contains, on the basis of mass percent, 0.030% to 0.100% C; 0.50% or less of Si; 1.00% to 2.50% Mn; more than 10.00% to 15.00% Cr; at least one selected from the group consisting of 0.01% to 0.50% Ti, 0.01% to 0.50% V, 0.01% to 1.00% Nb, and 0.01% to 1.00% Zr; N in an amount defined by the following expression, N: 0.005% to (Ti+V)×14/50+(Nb+Zr)×14/90; and the balance being Fe and incidental impurities.Type: GrantFiled: August 31, 2001Date of Patent: April 26, 2005Assignee: JFE Steel CorporationInventors: Yoshihiro Ozaki, Toshimitsu Nagaya, Atsushi Miyazaki, Susumu Satoh, Mineo Muraki, Setsuo Kakihara, Toshihiro Kasamo
-
Publication number: 20040244878Abstract: The soft Cr-containing steel includes, on a % by mass basis, C: from about 0.001% to about 0.020%, Si: more than about 0.10% and less than about 0.50%, Mn: less than about 2.00%, P: less than about 0.060%, S: less than about 0.008%, Cr: from about 12.0% to about 16.0%, Ni: from about 0.05% to about 1.00%, N: less than about 0.020%, Nb: from about 10×(C+N) to about 1.00%, Mo: more than about 0.80% and less than about 3.00%, wherein the contents of alloying elements, represented by Si and Mo, respectively, on a % by mass, satisfy the formula Si≦1.2−0.4Mo, so as to prevent precipitation of the Laves phase and to stably secure an effect of increasing high-temperature strength due to solid solution Mo.Type: ApplicationFiled: December 9, 2003Publication date: December 9, 2004Applicant: JFE STEEL CORPORATIONInventors: Atsushi Miyazaki, Junichiro Hirasawa, Mineo Muraki, Yoshihiro Yazawa, Osamu Furukimi
-
Patent number: 6786981Abstract: A ferritic stainless steel sheet for fuel tanks and fuel pipes comprises, by mass percent, about 0.1% or less of C; about 1.0% or less of Si; about 1.5% or less of Mn; about 0.06% or less of P; about 0.03% or less of S; about 1.0% or less of Al; about 11% to about 20% Cr; about 2.0% or less of Ni; about 0.5% to about 3.0% Mo; about 0.02% to about 1.0% V; about 0.04% or less of N; at least one of about 0.01% to about 0.8% Nb and about 0.01% to about 1.0% Ti; and the balance being Fe and incidental impurities. The ferritic stainless steel sheet is produced by rough-rolling a slab having the above composition; hot-rolling the rough-rolled sheet under a linear pressure of at least about 3.5 MN/m at a final pass in the finish rolling; cold-rolling the hot-rolled sheet at a gross reduction rate of at least about 75%; and annealing the cold-rolled sheet. The cold-rolling step includes one rolling stage or at least two rolling stages including intermediate annealing.Type: GrantFiled: December 11, 2001Date of Patent: September 7, 2004Assignee: JFE Steel CorporationInventors: Yoshihiro Yazawa, Mineo Muraki, Yoshihiro Ozaki, Kunio Fukuda, Atushi Miyazaki, Yasushi Katoh
-
Publication number: 20040159380Abstract: A ferritic stainless steel sheet for use in automobile fuel tanks and fuel pipes having smooth surface and resistance to organic acid is provided. The sheet contains, by mass, not more than about 0.1% C, not more than about 1.0 Si, not more than about 1.5% Mn, not more than about 0.06% P, not more than about 0.03% S, about 11% to about 23% Cr, not more than about 2.0% Ni, about 0.5% to about 3.0% Mo, not more than about 1.0% Al, not more than about 0.04% N, at least one of not more than about 0.8% Nb and not more than about 1.0% Ti, and the balance being Fe and unavoidable impurities, satisfying the relationship: 18≦Nb/(C+N)+2Ti/(C+N)≦60, wherein C, N, Nb, and Ti in the relationship represent the C, N, Nb, and Ti contents by mass percent, respectively. A process for making the same is also provided.Type: ApplicationFiled: February 17, 2004Publication date: August 19, 2004Applicant: JFE Steel CorporationInventors: Yoshihiro Yazawa, Osamu Furukimi, Mineo Muraki, Yoshihiro Ozaki, Kunio Fukuda, Yukihiro Baba
-
Patent number: 6758915Abstract: The invention is a grain-oriented magnetic steel sheet having extremely low iron loss, suitable for use as an iron core material for transformers and power generators, and a method for producing the same. The method includes forming a coating layer on a surface of a steel sheet having a thickness of 0.27 mm or less by vapor deposition in a low oxidizing atmosphere with an oxygen partial pressure (Po2) of less than 0.1 atm and a total pressure of 0.1 atm or more. The steel sheet has extremely low iron loss with a thickness of 0.27 mm or less and includes a coating layer formed by vapor deposition on a matrix surface.Type: GrantFiled: December 5, 2002Date of Patent: July 6, 2004Assignee: JFE Steel CorporationInventors: Minoru Takashima, Mineo Muraki, Hiroi Yamaguchi, Mitsumasa Kurosawa, Michiro Komatsubara
-
Patent number: 6740174Abstract: The soft Cr-containing steel includes, on a % by mass basis, C: from about 0.001% to about 0.020%, Si: more than about 0.10% and less than about 0.50%, Mn: less than about 2.00%, P: less than about 0.060%, S: less than about 0.008%, Cr: from about 12.0% to about 16.0%, Ni: from about 0.05% to about 1.00%, N: less than about 0.020%, Nb: from about 10×(C+N) to about 1.00%, Mo: more than about 0.80% and less than about 3.00%, wherein the contents of alloying elements, represented by Si and Mo, respectively, on a % by mass, satisfy the formula Si ≦1.2−0.4 Mo, so as to prevent precipitation of the Laves phase and to stably secure an effect of increasing high-temperature strength due to solid solution Mo.Type: GrantFiled: November 14, 2001Date of Patent: May 25, 2004Assignee: JFE Steel CorporationInventors: Atsushi Miyazaki, Junichiro Hirasawa, Mineo Muraki, Yoshihiro Yazawa, Osamu Furukimi
-
Publication number: 20040094240Abstract: A ferritic stainless steel sheet for fuel tanks and fuel pipes comprises, by mass percent, about 0.1% or less of C; about 1.0% or less of Si; about 1.5% or less of Mn; about 0.06% or less of P; about 0.03% or less of S; about 1.0% or less of Al; about 11% to about 20% Cr; about 2.0% or less of Ni; about 0.5% to about 3.0% Mo; about 0.02% to about 1.0% V; about 0.04% or less of N; at least one of about 0.01% to about 0.8% Nb and about 0.01% to about 1.0% Ti; and the balance being Fe and incidental impurities. The ferritic stainless steel sheet is produced by rough-rolling a slab having the above composition; hot-rolling the rough-rolled sheet under a linear pressure of at least about 3.5 MN/m at a final pass in the finish rolling; cold-rolling the hot-rolled sheet at a gross reduction rate of at least about 75%; and annealing the cold-rolled sheet. The cold-rolling step includes one rolling stage or at least two rolling stages including intermediate annealing.Type: ApplicationFiled: November 17, 2003Publication date: May 20, 2004Applicant: JFE Steel Corporation, a corporation of JapanInventors: Yoshihiro Yazawa, Mineo Muraki, Yoshihiro Ozaki, Kunio Fukuda, Atsushi Miyazaki, Yasushi Katoh
-
Publication number: 20040096352Abstract: The present invention provides a martensitic stainless steel sheet which is hard to be softened by tempering caused by heating during the use of a disk brake, can maintain the predetermined hardness, and has excellent punching workability, bending workability before quenching, and a particularly small shear drop, and in which a predetermined hardness after quenching is constantly achieved, in a low carbon martensitic stainless steel sheet used only after quenching. Specifically, the sheet contains, on the basis of mass percent, 0.030% to 0.100% C; 0.50% or less of Si; 1.00% to 2.50% Mn; more than 10.00% to 15.00% Cr; at least one selected from the group consisting-of 0.01% to 0.50% Ti, 0.01% to 0.50% V, 0.01% to 1.00% Nb, and 0.01% to 1.00% Zr; N in an amount defined by the following expression, N: 0.005% to (Ti+V)×{fraction (14/50)}+(Nb+Zr)×{fraction (14/90)}; and the balance being Fe and incidental impurities. The sheet further contains, on the basis of mass percent, more than 0.Type: ApplicationFiled: February 12, 2003Publication date: May 20, 2004Inventors: Yoshihiro Ozaki, Toshimitsu Nagaya, Atsushi Miyazaki, Susumu Satoh, Mineo Muraki, Setsuo Kakihara, Toshihiro Kasamo
-
Patent number: 6733601Abstract: A ferritic stainless steel sheet for use in automobile fuel tanks and fuel pipes having smooth surface and resistance to organic acid is provided. The sheet contains, by mass, not more than about 0.1% C, not more than about 1.0 Si, not more than about 1.5 % Mn, not more than about 0.06% P, not more than about 0.03% S, about 11% to about 23% Cr, not more than about 2.0% Ni, about 0.5% to about 3.0% Mo, not more than about 1.0% Al, not more than about 0.04% N, at least one of not more than about 0.8% Nb and not more than about 1.0% Ti, and the balance being Fe and unavoidable impurities, satisfying the relationship: 18≦Nb/(C+N)+2Ti/(C+N)≦60, wherein C, N, Nb, and. Ti in the relationship represent the C, N, Nb, and Ti contents by mass percent, respectively. A process for making the same is also provided.Type: GrantFiled: January 14, 2002Date of Patent: May 11, 2004Assignee: JFE Steel CorporationInventors: Yoshihiro Yazawa, Osamu Furukimi, Mineo Muraki, Yoshihiro Ozaki, Kunio Fukuda, Yukihiro Baba
-
Publication number: 20040035501Abstract: A ferritic stainless steel sheet for use in automobile fuel tanks and fuel pipes having smooth surface and resistance to organic acid is provided. The sheet contains, by mass, not more than about 0.1% C, not more than about 1.0 Si, not more than about 1.5% Mn, not more than about 0.06% P, not more than about 0.03% S, about 11% to about 23% Cr, not more than about 2.0% Ni, about 0.5% to about 3.0% Mo, not more than about 1.0% Al, not more than about 0.04% N, at least one of not more than about 0.8% Nb and not more than about 1.0% Ti, and the balance being Fe and unavoidable impurities, satisfying the relationship: 18≦Nb/(C+N)+2Ti/(C+N)≦60, wherein C, N, Nb, and Ti in the relationship represent the C, N, Nb, and Ti contents by mass percent, respectively. A process for making the same is also provided.Type: ApplicationFiled: August 25, 2003Publication date: February 26, 2004Applicant: Kawasaki Steel Corporation, a corporation of JapanInventors: Yoshihiro Yazawa, Osamu Furukimi, Mineo Muraki, Yoshihiro Ozaki, Kunio Fukuda, Yukihiro Baba
-
Publication number: 20030136470Abstract: The present invention relates to a grain-oriented magnetic steel sheet having extremely low iron loss, which is suitable for use as an iron core material for transformers and power generators, and to a method for producing the same. That is, in accordance with the present invention, a method for producing a grain-oriented magnetic steel sheet includes the step of forming a coating layer on a surface of the matrix of a steel sheet having a thickness of 0.27 mm or less by vapor deposition in a low oxidizing atmosphere with an oxygen partial pressure (Po2) of less than 0.1 atm and a total pressure of 0.1 atm or more. A grain-oriented magnetic steel sheet of the present invention having extremely low iron loss with a thickness of 0.27 mm or less includes a coating layer formed by vapor deposition on a matrix surface.Type: ApplicationFiled: December 5, 2002Publication date: July 24, 2003Inventors: Minoru Takashima, Mineo Muraki, Hiroi Kurosawa, Mitsumasa Kurosawa, Michiro Komatsubara
-
Patent number: 6521056Abstract: A ferritic stainless steel sheet which has not only superior high-temperature fatigue characteristics, but also superior workability at room temperatures. The steel sheet contains, by weight percent, C: not more than 0.02%, Si: 0.2 to 1.0%, Mn: not more than 1.5%, Cr: 11.0 to 20.0%, Ni: 0.05 to 2.0%, Mo: 1.0 to 2.0%, Al: not more than 1.0%, Nb: 0.2 to 0.8%, and N: not more than 0.02%, balance essentially Fe, and an aspect ratio (dRD/dTD) of grain size in planes at ¼ and ¾ sheet thickness, seen a direction normal to a sheet surface, in the range of 1.03 to 1.35. The steel sheet has a thickness greater than 0.3 mm but not greater than 2.5 mm, and a yield strength Y.S.≦360 MPa and an r-value≧1.3 at 30° C., and wherein after maintaining the steel sheet at 900° C. for one hour, the Y.S.≧18.0 MPa.Type: GrantFiled: July 25, 2001Date of Patent: February 18, 2003Assignee: Kawasaki Steel CorporationInventors: Mineo Muraki, Junichiro Hirasawa, Atsushi Miyazaki, Susumu Satoh
-
Publication number: 20020136661Abstract: A ferritic stainless steel sheet for use in automobile fuel tanks and fuel pipes having smooth surface and resistance to organic acid is provided. The sheet contains, by mass, not more than about 0.1% C, not more than about 1.0 Si, not more than about 1.5% Mn, not more than about 0.06% P, not more than about 0.03% S, about 11% to about 23% Cr, not more than about 2.0% Ni, about 0.5% to about 3.0% Mo, not more than about 1.0% Al, not more than about 0.04% N, at least one of not more than about 0.8% Nb and not more than about 1.0% Ti, and the balance being Fe and unavoidable impurities, satisfying the relationship: 18≦Nb/(C+N)+2Ti/(C+N)≦60, wherein C, N, Nb, and Ti in the relationship represent the C, N, Nb, and Ti contents by mass percent, respectively. A process for making the same is also provided.Type: ApplicationFiled: January 14, 2002Publication date: September 26, 2002Inventors: Yoshihiro Yazawa, Osamu Furukimi, Mineo Muraki, Yoshihiro Ozaki, Kunio Fukuda, Yukihiro Baba
-
Publication number: 20020117240Abstract: A ferritic stainless steel sheet for fuel tanks and fuel pipes comprises, by mass percent, about 0.1% or less of C; about 1.0% or less of Si; about 1.5% or less of Mn; about 0.06% or less of P; about 0.03% or less of S; about 1.0% or less of Al; about 11% to about 20% Cr; about 2.0% or less of Ni; about 0.5% to about 3.0% Mo; about 0.02% to about 1.0% V; about 0.04% or less of N; at least one of about 0.01% to about 0.8% Nb and about 0.01% to about 1.0% Ti; and the balance being Fe and incidental impurities. The ferritic stainless steel sheet is produced by rough-rolling a slab having the above composition; hot-rolling the rough-rolled sheet under a linear pressure of at least about 3.5 MN/m at a final pass in the finish rolling; cold-rolling the hot-rolled sheet at a gross reduction rate of at least about 75%; and annealing the cold-rolled sheet. The cold-rolling step includes one rolling stage or at least two rolling stages including intermediate annealing.Type: ApplicationFiled: December 11, 2001Publication date: August 29, 2002Inventors: Yoshihiro Yazawa, Mineo Muraki, Yoshihiro Ozaki, Kunio Fukuda, Atushi Miyazaki, Yasushi Katoh
-
Patent number: 6426039Abstract: Ferritic stainless steel comprising all three of Co, V, and B, having a Co content of about 0.01 mass % to about 0.3 mass %, a V content of about 0.01 mass % to about 0.3 mass %, and a B content of about 0.0002 mass % to about 0.0050 mass %, and having superior secondary working embrittleness resistance and superior high temperature fatigue characteristics.Type: GrantFiled: June 27, 2001Date of Patent: July 30, 2002Assignee: Kawasaki Steel CorporationInventors: Junichiro Hirasawa, Atsushi Miyazaki, Mineo Muraki, Susumu Satoh
-
Publication number: 20020098107Abstract: The soft Cr-containing steel includes, on a % by mass basis, C: from about 0.001% to about 0.020%, Si: more than about 0.10% and less than about 0.50%, Mn: less than about 2.00%, P: less than about 0.060%, S: less than about 0.008%, Cr: from about 12.0% to about 16.0%, Ni: from about 0.05% to about 1.00%, N: less than about 0.020%, Nb: from about 10×(C+N) to about 1.00%, Mo: more than about 0.80% and less than about 3.00%, wherein the contents of alloying elements, represented by Si and Mo, respectively, on a % by mass, satisfy the formula Si ≦1.2-0.4 Mo, so as to prevent precipitation of the Laves phase and to stably secure an effect of increasing high-temperature strength due to solid solution Mo.Type: ApplicationFiled: November 14, 2001Publication date: July 25, 2002Applicant: Kawasaki Steel CorporationInventors: Atsushi Miyazaki, Junichiro Hirasawa, Mineo Muraki, Yoshihiro Yazawa, Osamu Furukimi
-
Publication number: 20020036036Abstract: A ferritic stainless steel sheet which has not only superior high-temperature fatigue characteristics, but also superior workability at room temperatures. The steel sheet contains, by weight percent, C: not more than 0.02%, Si: 0.2 to 1.0%, Mn: not more than 1.5%, Cr: 11.0 to 20.0%, Ni: 0.05 to 2.0%, Mo: 1.0 to 2.0%, Al: not more than 1.0%, Nb: 0.2 to 0.8%, and N: not more than 0.02%, balance essentially Fe, and an aspect ratio (dRD/dTD) of grain size in planes at ¼ and ¾ sheet thickness, seen a direction normal to a sheet surface, in the range of 1.03 to 1.35. The steel sheet has a thickness greater than 0.3 mm but not greater than 2.5 mm, and a yield strength Y.S.≦360 MPa and an r-value≧1.3 at 30° C., and wherein after maintaining the steel sheet at 90° C. for one hour, the Y.S.≧18.0 MPa.Type: ApplicationFiled: July 25, 2001Publication date: March 28, 2002Applicant: Kawasaki Steel CorporationInventors: Mineo Muraki, Junichiro Hirasawa, Atsushi Miyazaki, Susumu Satoh
-
Publication number: 20020007876Abstract: Ferritic stainless steel comprising all three of Co, V, and B, having a Co content of about 0.01 mass % to about 0.3 mass %, a V content of about 0.01 mass % to about 0.3 mass %, and a B content of about 0.0002 mass % to about 0.0050 mass %, and having superior secondary working embrittleness resistance and superior high temperature fatigue characteristics.Type: ApplicationFiled: June 27, 2001Publication date: January 24, 2002Applicant: Kawasaki Steel CorporationInventors: Junichiro Hirasawa, Atsushi Miyazaki, Mineo Muraki, Susumu Satoh
-
Patent number: 6136456Abstract: Grain oriented electrical steel sheet with a very low iron loss and a method for producing the same, wherein the surface of the iron substrate of the grain oriented electrical steel sheet is subjected to an enhancement treatment of crystal grain orientation or surface smoothing to a mean roughness of about 0.20 .mu.m or less, electroplating a chromium plating layer on the substrate with heterogeneous growth, and applying a tension coating film to the plating layer.Type: GrantFiled: October 23, 1998Date of Patent: October 24, 2000Assignee: Kawasaki Steel CorporationInventors: Michiro Komatsubara, Hiroi Yamaguchi, Minoru Takashima, Mineo Muraki
-
Patent number: 5885371Abstract: A method of producing a grain-oriented magnetic steel sheet exhibiting a very low core loss and high magnetic flux density uses a slab of silicon steel containing Al, B, N, and S and/or Se. The method employs hot rolling conducted such that the rolling reduction falls within the range of from about 85 to 99%, and the hot-rolling finish temperature falls within the range of from 950.degree. to 1150.degree. C. and is based on the contents of Si, Al and B. The hot-rolled steel sheet is rapidly cooled at a cooling rate of about 20.degree. C./s and is coiled at a temperature of about 670.degree. C. or lower. Hot-rolled sheet annealing or intermediate annealing is executed by heating the hot-rolled steel sheet up to about 800.degree. C. at a heating rate of from 5.degree. to 25.degree. C./s and holding at a temperature of from about 800.degree. to 1125.degree. C. for a period not longer than about 150 seconds.Type: GrantFiled: October 9, 1997Date of Patent: March 23, 1999Assignee: Kawasaki Steel CorporationInventors: Michiro Komatsubara, Toshito Takamiya, Kunihiro Senda, Mineo Muraki, Chizuko Goto, Mitsumasa Kurosawa, Kazuaki Tamura