Patents by Inventor Masayuki Wakita
Masayuki Wakita 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).
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Patent number: 11401571Abstract: A hot-rolled steel sheet includes a specific chemical composition, and includes a microstructure represented by, in vol %: retained austenite: 2% to 30%; ferrite: 20% to 85%; bainite: 10% to 60%; pearlite: 5% or less; and martensite: 10% or less. A proportion of grains having an intragranular misorientation of 5° to 14° in all grains is 5% to 50% by area ratio, the grain being defined as an area which is surrounded by a boundary having a misorientation of 15° or more and has a circle-equivalent diameter of 0.3 ?m or more.Type: GrantFiled: February 20, 2015Date of Patent: August 2, 2022Assignee: NIPPON STEEL CORPORATIONInventors: Tatsuo Yokoi, Mitsuru Yoshida, Natsuko Sugiura, Hiroshi Shuto, Masayuki Wakita
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Patent number: 10913988Abstract: A hot-rolled steel sheet includes a predetermined chemical composition, and a structure which include, by area ratio, ferrite and bainite in a range of 80% to 98% in total, and martensite in a range of 2% to 10%, in which in the structure, in a case where a boundary having an orientation difference of equal to or greater than 15° is defined as a grain boundary, and an area which is surrounded by the grain boundary, and has an equivalent circle diameter of equal to or greater than 0.3 ?m is defined as a grain, the ratio of the grains having an intragranular orientation difference in a range of 5° to 14° is, by area ratio, in a range of 10% to 60%.Type: GrantFiled: February 22, 2016Date of Patent: February 9, 2021Assignee: NIPPON STEEL CORPORATIONInventors: Hiroshi Shuto, Natsuko Sugiura, Mitsuru Yoshida, Tatsuo Yokoi, Masayuki Wakita
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Patent number: 10774412Abstract: A hot-dip galvanized cold-rolled steel sheet has a tensile strength of 750 MPa or higher, a composition consisting, in mass percent, C: more than 0.10% and less than 0.25%, Si: more than 0.50% and less than 2.0%, Mn: more than 1.50% and 3.0% or less, and optionally containing one or more types of Ti, Nb, V, Cr, Mo, B, Ca, Mg, REM, and Bi, P: less than 0.050%, S: 0.010% or less, sol. Al: 0.50% or less, and N: 0.010% or less, and a main phase as a low-temperature transformation product and a second phase as retained austenite. The retained austenite volume fraction is more than 4.0% and less than 25.0% of the whole structure, and has an average grain size of less than 0.80 ?m. A number density of retained austenite grains having a grain size of 1.2 ?m or more is 3.0×10?2/?m2 or less.Type: GrantFiled: June 29, 2012Date of Patent: September 15, 2020Assignee: NIPPON STEEL CORPORATIONInventors: Norio Imai, Masayuki Wakita, Takuya Nishio, Jun Haga, Kengo Hata, Yasuaki Tanaka, Mitsuru Yoshida, Hiroshi Takebayashi, Suguhiro Fukushima, Toshiro Tomida
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Patent number: 10752972Abstract: A hot-rolled steel sheet includes a predetermined chemical composition, and a structure which includes, by area ratio, a ferrite in a range of 5% to 60% and a bainite in a range of 30% to 95%, in which in the structure, in a case where a boundary having an orientation difference of equal to or greater than 15° is defined as a grain boundary, and an area which is surrounded by the grain boundary and has an equivalent circle diameter of equal to or greater than 0.3 ?m is defined as a grain, the ratio of the grains having an intragranular orientation difference in a range of 5° to 14° is, by area ratio, in a range of 20% to 100%.Type: GrantFiled: February 22, 2016Date of Patent: August 25, 2020Assignee: NIPPON STEEL CORPORATIONInventors: Natsuko Sugiura, Mitsuru Yoshida, Hiroshi Shuto, Tatsuo Yokoi, Masayuki Wakita
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Patent number: 10689737Abstract: A hot-rolled steel sheet includes a chemical composition represented by, in mass %, C: 0.010% to 0.100%, Si: 0.30% or less, Cr: 0.05% to 1.00%, Nb: 0.003% to 0.050%, Ti: 0.003% to 0.200% and others, wherein a proportion of grains having an intragranular misorientation of 5° to 14° in all grains is 20% or more by area ratio, the grain being defined as an area which is surrounded by a boundary having a misorientation of 15° or more and has a circle-equivalent diameter of 0.3 ?m or more.Type: GrantFiled: February 25, 2015Date of Patent: June 23, 2020Assignee: NIPPON STEEL CORPORATIONInventors: Masayuki Wakita, Mitsuru Yoshida, Natsuko Sugiura, Hiroshi Shuto, Tatsuo Yokoi
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Patent number: 10174392Abstract: A method for producing a high-tensile cold-rolled steel sheet includes subjecting a slab having a composition containing C: more than 0.020% and less than 0.30%, Si: more than 0.10% and 3.00% or less, and Mn: more than 1.00% and 3.50% or less to hot rolling wherein the roll draft of the final one pass is higher than 15%, and rolling is finished in the temperature region of Ar3 point or higher, optionally annealing wherein the hot-rolled steel sheet is heated to 300° C. or higher after being cooled to 780° C. or lower, coiling higher than 400° C. or lower than 400° C., cold rolling the hot-rolled steel sheet or the annealed steel sheet, and annealing wherein the cold-rolled steel sheet is soaked in the temperature region of (Ac3 point?40° C.) or higher, cooling to 500° C. or lower and 300° C. or higher, and holding in that temperature region for 30 seconds or longer.Type: GrantFiled: July 2, 2012Date of Patent: January 8, 2019Assignee: NIPPON STEEL & SUMITOMO METAL CORPORATIONInventors: Jun Haga, Takuya Nishio, Masayuki Wakita, Yasuaki Tanaka, Norio Imai, Toshiro Tomida, Mitsuru Yoshida, Kengo Hata
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Publication number: 20180044749Abstract: A hot-rolled steel sheet includes a predetermined chemical composition, and a structure which include, by area ratio, ferrite and bainite in a range of 80% to 98% in total, and martensite in a range of 2% to 10%, in which in the structure, in a case where a boundary having an orientation difference of equal to or greater than 15° is defined as a grain boundary, and an area which is surrounded by the grain boundary, and has an equivalent circle diameter of equal to or greater than 0.3 ?m is defined as a grain, the ratio of the grains having an intragranular orientation difference in a range of 5° to 14° is, by area ratio, in a range of 10% to 60%.Type: ApplicationFiled: February 22, 2016Publication date: February 15, 2018Applicant: NIPPON STEEL & SUMITOMO METAL CORPORATIONInventors: Hiroshi SHUTO, Natsuko SUGIURA, Mitsuru YOSHIDA, Tatsuo YOKOI, Masayuki WAKITA
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Publication number: 20180037980Abstract: A hot-rolled steel sheet includes a chemical composition represented by, in mass %, C: 0.010% to 0.100%, Si: 0.30% or less, Cr: 0.05% to 1.00%, Nb: 0.003% to 0.050%, Ti: 0.003% to 0.200% and others, wherein a proportion of grains having an intragranular misorientation of 5° to 14° in all grains is 20% or more by area ratio, the grain being defined as an area which is surrounded by a boundary having a misorientation of 15° or more and has a circle-equivalent diameter of 0.3 ?m or more.Type: ApplicationFiled: February 25, 2015Publication date: February 8, 2018Applicant: NIPPON STEEL & SUMITOMO METAL CORPORATIONInventors: Masayuki WAKITA, Mitsuru YOSHIDA, Natsuko SUGIURA, Hiroshi SHUTO, Tatsuo YOKOI
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Publication number: 20180037967Abstract: A hot-rolled steel sheet includes a predetermined chemical composition, and a structure which includes, by area ratio, a ferrite in a range of 5% to 60% and a bainite in a range of 30% to 95%, in which in the structure, in a case where a boundary having an orientation difference of equal to or greater than 15° is defined as a grain boundary, and an area which is surrounded by the grain boundary and has an equivalent circle diameter of equal to or greater than 0.3 ?m is defined as a grain, the ratio of the grains having an intragranular orientation difference in a range of 5° to 14° is, by area ratio, in a range of 20% to 100%.Type: ApplicationFiled: February 22, 2016Publication date: February 8, 2018Applicant: NIPPON STEEL & SUMITOMO METAL CORPORATIONInventors: Natsuko SUGIURA, Mitsuru YOSHIDA, Hiroshi SHUTO, Tatsuo YOKOI, Masayuki WAKITA
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Publication number: 20180023162Abstract: A hot-rolled steel sheet includes a predetermined chemical composition, and a structure which includes, by area ratio, ferrite and bainite in a range of 75% to 95% in total, and martensite in a range of 5% to 20%, in which in the structure, in a case where a boundary having an orientation difference of equal to or greater than 15° is set as a grain boundary, and an area which is surrounded by the grain boundary, and has an equivalent circle diameter of equal to or greater than 0.3 ?m is defined as a grain, the ratio of the grains having an intragranular orientation difference in a range of 5° to 14° is, by area ratio, in a range of 10% to 60%.Type: ApplicationFiled: February 20, 2015Publication date: January 25, 2018Applicant: NIPPON STEEL & SUMITOMO METAL CORPORATIONInventors: Natsuko SUGIURA, Mitsuru YOSHIDA, Hiroshi SHUTO, Tatsuo YOKOI, Masayuki WAKITA
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Publication number: 20170349967Abstract: A hot-rolled steel sheet includes a specific chemical composition, and includes a microstructure represented by, in vol %: retained austenite: 2% to 30%; ferrite: 20% to 85%; bainite: 10% to 60%; pearlite: 5% or less; and martensite: 10% or less. A proportion of grains having an intragranular misorientation of 5° to 14° in all grains is 5% to 50% by area ratio, the grain being defined as an area which is surrounded by a boundary having a misorientation of 15° or more and has a circle-equivalent diameter of 0.3 ?m or more.Type: ApplicationFiled: February 20, 2015Publication date: December 7, 2017Applicant: NIPPON STEEL & SUMITOMO METAL CORPORATIONInventors: Tatsuo YOKOI, Mitsuru YOSHIDA, Natsuko SUGIURA, Hiroshi SHUTO, Masayuki WAKITA
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Patent number: 9809874Abstract: A steel sheet suitable as a starting material for a vehicle impact absorbing member with high absorption of impact energy and resistance to cracking contains, by mass %, C: 0.08-0.30%, Mn: 1.5-3.5%; Si+Al: 0.50-3.0%, P: 0.10% or less, S: at most 0.010%, and N: at most 0.010%, and optionally, one or more types selected from Cr: at most 0.5%, Mo: at most 0.5% , B: at most 0.010%, Ti: less than 0.04%, Nb: less than 0.030%, V: less than 0.5%, Ca: at most 0.010%, Mg: at most 0.010%, REM: at most 0.050%, and Bi: at most 0.050%. The microstructure contains, by area %, bainite: more than 50%, martensite: 3-30%, and retained austenite: 3-15%, the remainder comprising ferrite having an average grain diameter of less than 5 mm. The product of uniform elongation and hole expansion ratio is at least 300%2 and 5% effective flow stress is at least 900 MPa.Type: GrantFiled: April 8, 2013Date of Patent: November 7, 2017Assignee: NIPPON STEEL & SUMITOMO METAL CORPORATIONInventors: Yasuaki Tanaka, Kaori Kawano, Masahito Tasaka, Yoshiaki Nakazawa, Takuya Nishio, Masayuki Wakita, Jun Haga, Toshiro Tomida
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Patent number: 9523139Abstract: A high-strength cold-rolled steel sheet excellent in ductility, work hardenability, and stretch flangeability, and having tensile strength of 780 MPa or more includes: a chemical composition containing, in mass percent, C: more than 0.020% to less than 0.30%, Si: more than 0.10% to 3.00% or less, Mn: more than 1.00% to 3.50% or less; and metallurgical structure whose main phase is a low-temperature transformation product, and whose secondary phase contains retained austenite. The retained austenite has a volume fraction relative to overall structure of more than 4.0% to less than 25.0% and an average grain size of less than 0.80 ?m, and of the retained austenite, the number density of retained austenite grains whose grain size is 1.2 ?m or more is 3.0×10?2 grains/?m2 or less.Type: GrantFiled: June 27, 2012Date of Patent: December 20, 2016Assignee: NIPPON STEEL & SUMITOMO METAL CORPORATIONInventors: Jun Haga, Takuya Nishio, Masayuki Wakita, Yasuaki Tanaka, Norio Imai, Toshiro Tomida
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Publication number: 20160285674Abstract: A data center system includes an information processing apparatus and a plurality of data centers. The information processing apparatus includes a detection unit, a storage unit, and an extraction unit. The detection unit detects a fault in a system operated in each of the data centers. The storage unit stores fault-handling information regarding a handling method of a fault that occurred in a past. The extraction unit extracts, when the fault-handling information includes information regarding the handling method which is adapted in the past to address the detected fault occurred in a first data center among the data centers, the information regarding the handling method. Otherwise, the extraction unit extracts information regarding the handling method which is adapted in the past to address the detected fault occurred in a second data center other than the first data center.Type: ApplicationFiled: January 20, 2016Publication date: September 29, 2016Applicant: FUJITSU LIMITEDInventor: Masayuki Wakita
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Publication number: 20160283306Abstract: A receiving unit receives information on a failure that has occurred in each of data centers arranged in a plurality of locations. A specifying unit compares area information that indicates a characteristic related to a failure in the data center in which the failure has occurred with area information that is associated with an engineer based on a task, and specifies, as a failure handling candidate from among engineers, an engineer who is associated with area information that is similar to the area information that indicates the characteristic related to the failure in the data center in which the failure has occurred.Type: ApplicationFiled: February 4, 2016Publication date: September 29, 2016Applicant: FUJITSU LIMITEDInventors: Yusuke HAYASHI, Masayuki WAKITA
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Publication number: 20160196189Abstract: A failure monitoring device includes a selecting unit and a migration control unit. The selecting unit selects, when a failure related to software occurs in a system that is operated in one of data centers that are arranged in geographically separate locations and that can communicate with each other, an engineer who handles the failure. The migration control unit migrates, when an engineer belonging to another data center that is different from the data center in which the system is operated is selected by the selecting unit, the system to the another data center.Type: ApplicationFiled: December 22, 2015Publication date: July 7, 2016Applicant: FUJITSU LIMITEDInventors: Koyo Miyagi, Hideki Sakurai, Yusuke Hayashi, Masayuki Wakita
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Patent number: 9034118Abstract: A method for manufacturing a hot-rolled sheet attains grain refinement of the steel sheet whose grain size is extremely fine. In particular, a ferrite grain size of less than average 2 ?m is obtained, which is not laminar but has ferrite grains with equiaxed morphology and exhibits high formability in forming. The method comprises the steps of rolling and cooling, wherein the rolling reductions, cooling steps, and temperature are closely regulated. A hot rolled sheet made from the method of manufacturing has a controlled ferrite grain in different regions of sheet thickness.Type: GrantFiled: March 11, 2013Date of Patent: May 19, 2015Assignee: NIPPON STEEL & SUMITOMO METAL CORPORATIONInventors: Suguhiro Fukushima, Manabu Eto, Tamotsu Sasaki, Kaori Kawano, Masayuki Wakita
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Publication number: 20150075680Abstract: A steel sheet suitable as a starting material for a vehicle impact absorbing member with high absorption of impact energy and resistance to cracking contains, by mass %, C: 0.08-0.30%, Mn: 1.5-3.5%; Si+Al: 0.50-3.0%, P: 0.10% or less, S: at most 0.010%, and N: at most 0.010%, and optionally, one or more types selected from Cr: at most 0.5%, Mo: at most 0.5%, B: at most 0.010%, Ti: less than 0.04%, Nb: less than 0.030%, V: less than 0.5%, Ca: at most 0.010%, Mg: at most 0.010%, REM: at most 0.050%, and Bi: at most 0.050%. The microstructure contains, by area %, bainite: more than 50%, martensite: 3-30%, and retained austenite: 3-15%, the remainder comprising ferrite having an average grain diameter of less than 5 mm. The product of uniform elongation and hole expansion ratio is at least 300%2 and 5% effective flow stress is at least 900 MPa.Type: ApplicationFiled: April 8, 2013Publication date: March 19, 2015Inventors: Yasuaki Tanaka, Kaori Kawano, Masahito Tasaka, Yoshiaki Nakazawa, Takuya Nishio, Masayuki Wakita, Jun Haga, Toshiro Tomida
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Publication number: 20140241933Abstract: A high-strength cold-rolled steel sheet excellent in ductility, work hardenability, and stretch flangeability, and having tensile strength of 780 MPa or more includes: a chemical composition containing, in mass percent, C: more than 0.020% to less than 0.30%, Si: more than 0.10% to 3.00% or less, Mn: more than 1.00% to 3.50% or less; and metallurgical structure whose main phase is a low-temperature transformation product, and whose secondary phase contains retained austenite. The retained austenite has a volume fraction relative to overall structure of more than 4.0% to less than 25.0% and an average grain size of less than 0.80 ?m, and of the retained austenite, the number density of retained austenite grains whose grain size is 1.2 ?m or more is 3.0×10?2 grains/?m2 or less.Type: ApplicationFiled: June 27, 2012Publication date: August 28, 2014Applicant: NIPPON STEEL & SUMITOMO METAL CORPORATIONInventors: Jun Haga, Takuya Nishio, Masayuki Wakita, Yasuaki Tanaka, Norio Imai, Toshiro Tomida
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Publication number: 20140238557Abstract: A method for producing a high-tensile cold-rolled steel sheet includes subjecting a slab having a composition containing C: more than 0.020% and less than 0.30%, Si: more than 0.10% and 3.00% or less, and Mn: more than 1.00% and 3.50% or less to hot rolling wherein the roll draft of the final one pass is higher than 15%, and rolling is finished in the temperature region of Ar3 point or higher, optionally annealing wherein the hot-rolled steel sheet is heated to 300° C. or higher after being cooled to 780° C. or lower, coiling higher than 400° C. or lower than 400° C., cold rolling the hot-rolled steel sheet or the annealed steel sheet, and annealing wherein the cold-rolled steel sheet is soaked in the temperature region of (Ac3 point?40° C.) or higher, cooling to 500° C. or lower and 300° C. or higher, and holding in that temperature region for 30 seconds or longer.Type: ApplicationFiled: July 2, 2012Publication date: August 28, 2014Applicant: NIPPON STEEL & SUMITOMO METAL CORPORATIONInventors: Jun Haga, Takuya Nishio, Masayuki Wakita, Yasuaki Tanaka, Norio Imai, Toshiro Tomida, Mitsuru Yoshida, Kengo Hata