Patents by Inventor Satoshi Hirosawa

Satoshi Hirosawa 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: 9418786
    Abstract: An R—Fe—B based porous magnet according to the present invention has an aggregate structure of Nd2Fe14B type crystalline phases with an average grain size of 0.1 ?m to 1 ?m. At least a portion of the magnet is porous and has micropores with a major axis of 1 ?m to 20 ?m.
    Type: Grant
    Filed: August 16, 2012
    Date of Patent: August 16, 2016
    Assignee: HITACHI METALS, LTD.
    Inventors: Takeshi Nishiuchi, Noriyuki Nozawa, Satoshi Hirosawa, Tomohito Maki, Katsunori Bekki
  • Publication number: 20130068992
    Abstract: An R-T-B based permanent magnet powder, which has been made by an HDDR process and which has an average crystal grain size of 0.1 ?m to 1 ?m and a crystal grain aspect ratio (ratio of the major axis size to the minor axis size) of 2 or less, is provided (Step (A)). R is a rare-earth element, of which at least 95 at % is Nd and/or Pr, and T is either Fe alone or Fe partially replaced with Co and/or Ni and is a transition metal element, of which at least 50 at % is Fe. Meanwhile, an R?—Cu based alloy powder, which is made up of R? and Cu, which accounts for 2 at % to 50 at % of the alloy powder, is also provided (Step (B)). R? is a rare-earth element, of which at least 90 at % is Nd and/or Pr but which includes neither Dy nor Tb. The R-T-B based permanent magnet powder and the R?—Cu based alloy powder are mixed together to obtain a mixed powder (Step (C)). And then the mixed powder is subjected to a heat treatment process at a temperature of 500° C. to 900° C.
    Type: Application
    Filed: May 19, 2011
    Publication date: March 21, 2013
    Inventors: Kazuhiro Hono, Tadakatsu Ohkubo, Hossein Sepehri Amin, Noriyuki Nozawa, Takeshi Nishiuchi, Satoshi Hirosawa
  • Publication number: 20120306308
    Abstract: An R—Fe—B based porous magnet according to the present invention has an aggregate structure of Nd2Fe14B type crystalline phases with an average grain size of 0.1 ?m to 1 ?m. At least a portion of the magnet is porous and has micropores with a major axis of 1 ?m to 20 ?m.
    Type: Application
    Filed: August 16, 2012
    Publication date: December 6, 2012
    Applicant: HITACHI METALS, LTD.
    Inventors: Takeshi NISHIUCHI, Noriyuki NOZAWA, Satoshi HIROSAWA, Tomohito MAKI, Katsunori BEKKI
  • Patent number: 8268093
    Abstract: An R—Fe—B based porous magnet according to the present invention has an aggregate structure of Nd2Fe14B type crystalline phases with an average grain size of 0.1 ?m to 1 ?m. At least a portion of the magnet is porous and has micropores with a major axis of 1 ?m to 20 ?m.
    Type: Grant
    Filed: May 18, 2007
    Date of Patent: September 18, 2012
    Assignee: Hitachi Metals, Ltd.
    Inventors: Takeshi Nishiuchi, Noriyuki Nozawa, Satoshi Hirosawa, Tomohito Maki, Katsunori Bekki
  • Patent number: 8128758
    Abstract: An R—Fe—B based rare-earth alloy powder with a mean particle size of less than about 20 ?m is provided and compacted to make a powder compact. Next, the powder compact is subjected to a heat treatment at a temperature of about 550° C. to less than about 1,000° C. within hydrogen gas, thereby producing hydrogenation and disproportionation reactions (HD processes). Then, the powder compact is subjected to another heat treatment at a temperature of about 550° C. to less than about 1,000° C. within either a vacuum or an inert atmosphere, thereby producing desorption and recombination reactions and obtaining a porous material including fine crystal grains, of which the density is about 60% to about 90% of their true density and which have an average crystal grain size of about 0.01 ?m to about 2 ?m (DR processes). Thereafter, the porous material is subjected to yet another heat treatment at a temperature of about 750° C. to less than about 1,000° C.
    Type: Grant
    Filed: October 21, 2008
    Date of Patent: March 6, 2012
    Assignee: Hitachi Metals, Ltd.
    Inventors: Noriyuki Nozawa, Takeshi Nishiuchi, Satoshi Hirosawa, Tomohito Maki
  • Patent number: 7988797
    Abstract: A nanocomposite magnet according to the present invention has a composition represented by the general formula: RxQyMz(Fe1-mTm)bal, where R is at least one rare-earth element, Q is at least one element selected from the group consisting of B and C, M is at least one metal element that is selected from the group consisting of Al, Si, Ti, V, Cr, Mn, Cu, Zn, Ga, Zr, Nb, Mo, Ag, Hf, Ta, W, Pt, Au and Pb and that always includes Ti, and T is at least one element selected from the group consisting of Co and Ni. The mole fractions x, y, z and m satisfy the inequalities of 6 at %?x<10 at %, 10 at %?y?17 at %, 0.5 at %?z?6 at % and 0?m?0.5, respectively. The nanocomposite magnet includes a hard magnetic phase and a soft magnetic phase that are magnetically coupled together. The hard magnetic phase is made of an R2Fe14B-type compound, and the soft magnetic phase includes an ?-Fe phase and a crystalline phase with a Curie temperature of 610° C. to 700° C. (? phase) as its main phases.
    Type: Grant
    Filed: May 17, 2010
    Date of Patent: August 2, 2011
    Assignee: Hitachi Metals, Ltd.
    Inventors: Yasutaka Shigemoto, Satoshi Hirosawa, Toshio Miyoshi
  • Publication number: 20100219922
    Abstract: A nanocomposite magnet according to the present invention has a composition represented by the general formula: RxQyMz(Fe1-mTm)bal, where R is at least one rare-earth element, Q is at least one element selected from the group consisting of B and C, M is at least one metal element that is selected from the group consisting of Al, Si, Ti, V, Cr, Mn, Cu, Zn, Ga, Zr, Nb, Mo, Ag, Hf, Ta, W, Pt, Au and Pb and that always includes Ti, and T is at least one element selected from the group consisting of Co and Ni. The mole fractions x, y, z and m satisfy the inequalities of 6 at %?x<10 at %, 10 at %?y?17 at %, 0.5 at %?z?6 at % and 0?m?0.5, respectively. The nanocomposite magnet includes a hard magnetic phase and a soft magnetic phase that are magnetically coupled together. The hard magnetic phase is made of an R2Fe14B-type compound, and the soft magnetic phase includes an ?-Fe phase and a crystalline phase with a Curie temperature of 610° C. to 700° C. (? phase) as its main phases.
    Type: Application
    Filed: May 17, 2010
    Publication date: September 2, 2010
    Applicant: HITACHI METALS, LTD.
    Inventors: Yasutaka SHIGEMOTO, Satoshi HIROSAWA, Toshio MIYOSHI
  • Patent number: 7670443
    Abstract: A method of making a magnetic alloy material includes the steps of: preparing a melt of an alloy material having a predetermined composition; rapidly cooling and solidifying the melt to obtain a rapidly solidified alloy represented by: Fe100-a-b-cREaAbTMc where RE is at least one rare-earth element selected from La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er and Tm and including at least about 90 at % of La; A is at least one element selected from Al, Si, Ga, Ge and Sn; TM is at least one transition metal element selected from Sc, Ti, V, Cr, Mn, Co, Ni, Cu and Zn; and 5 at %?a?10 at %, 4.7 at %?b?18 at % and 0 at %?c?9 at %; and producing a compound phase having an NaZn13-type crystal structure in at least about 70 vol % of the rapidly solidified alloy.
    Type: Grant
    Filed: February 12, 2007
    Date of Patent: March 2, 2010
    Assignee: Hitachi Metals, Ltd.
    Inventors: Ryosuke Kogure, Hirokazu Kanekiyo, Takeshi Nishiuchi, Satoshi Hirosawa
  • Patent number: 7578892
    Abstract: A magnetic alloy material according to the present invention has a composition represented by Fe100-a-b-cREaAbCoc, where RE is a rare-earth element always including La, A is either Si or Al, 6 at %?a?11 at %, 8 at %?b?18 at %, and 0 at %?c?9 at %, and has either a two phase structure consisting essentially of an ?-Fe phase and an (RE, Fe, A) phase including 30 at % to 90 at % of RE or a three phase structure consisting essentially of the ?-Fe phase, the (RE, Fe, A) phase including 30 at % to 90 at % of RE and an RE(Fe, A)13 compound phase with an NaZn13-type crystal structure. The respective phases have an average minor-axis size of 40 nm to 2 ?m.
    Type: Grant
    Filed: March 30, 2006
    Date of Patent: August 25, 2009
    Assignee: Hitachi Metals, Ltd.
    Inventors: Satoshi Hirosawa, Hiroyuki Tomizawa, Ryosuke Kogure
  • Patent number: 7547365
    Abstract: To make a raw alloy, consisting mostly of amorphous structure, highly productively and at a reduced cost for a nanocomposite magnet, a molten alloy represented by Fe100-x-y-zRxQyMz (where R is at least one element selected from Pr, Nd, Dy and Tb; Q is B and/or C; M is at least one element selected from Co, Al, Si, Ti, V, Cr, Mn, Ni, Cu, Ga, Zr, Nb, Mo, Ag, Pt, Au and Pb; and 1 at %?x<6 at %, 15 at %?y?30 at % and 0 at %?z?7 at %) is prepared. This molten alloy is rapidly cooled by a strip casting process in which the alloy is fed onto a chill roller, rotating at a peripheral velocity of 3 m/s to less than 20 m/s, at a feeding rate per unit contact width of 0.2 kg/min/cm to 5.2 kg/min/cm. In this manner, an alloy including at least 60 volume percent of amorphous phase can be obtained.
    Type: Grant
    Filed: November 28, 2005
    Date of Patent: June 16, 2009
    Assignee: Hitachi Metals, Ltd.
    Inventors: Ryo Murakami, Hirokazu Kanekiyo, Satoshi Hirosawa
  • Publication number: 20090129966
    Abstract: An iron-based rare-earth nanocomposite magnet according to the present invention includes an Nd2Fe14B phase and an ?-Fe phase and has a composition represented by the compositional formula: T100-x-y-z-n(B1-qCq)xRyTizMn, where T is at least one transition metal element selected from the group consisting of Fe, Co and Ni and always including Fe, R is at least one rare-earth element including substantially no La or Ce, and M is at least one metal element selected from the group consisting of Al, Si, V, Cr, Mn, Cu, Zn, Ga, Zr, Nb, Mo, Ag, Hf, Ta, W, Pt, Au and Pb, and the mole fractions x, y, z, n and q satisfy the inequalities of: 4 at %?x?10 at %, 6 at %?y?10 at %, 0.05 at %?z?5 at %, 0 at %?n?10 at %, and 0.05?q?0.5, respectively. The magnet includes 5 vol % to 60 vol % of ?-Fe phase with an average crystal grain size of 1 nm to 50 nm and 40 vol % to 90 vol % of Nd2Fe14B phase with an average crystal grain size of 5 nm to 100 nm.
    Type: Application
    Filed: March 22, 2006
    Publication date: May 21, 2009
    Applicant: Hitachi Metals, Ltd.
    Inventors: Hirokazu Kanekiyo, Toshio Miyoshi, Satoshi Hirosawa
  • Publication number: 20090123774
    Abstract: An R—Fe—B based porous magnet according to the present invention has an aggregate structure of Nd2Fe14B type crystalline phases with an average grain size of 0.1 ?m to 1 ?m. At least a portion of the magnet is porous and has micropores with a major axis of 1 ?m to 20 ?m.
    Type: Application
    Filed: May 18, 2007
    Publication date: May 14, 2009
    Inventors: Takeshi Nishiuchi, Noriyuki Nozawa, Satoshi Hirosawa, Tomohito Maki, Katsunori Bekki
  • Patent number: 7507302
    Abstract: A rare-earth alloy powder is obtained by rapidly cooling a melt of an alloy by an atomization process. The alloy has a composition represented by (Fe1-mTm)100-x-y-zQxRyTizMn, where T is at least one of Co and Ni, Q is at least one of B and C, R is at least one of the rare-earth metal elements and yttrium, and M is at least one of Nb, Zr, Mo, Ta and Hf. The mole fractions x, y, z, m and n satisfy 10 at %<x?25 at %, 6 at %?y<10 at %, 0.1 at %?z?12 at %, 0?m?0.5, and 0 at %?n?10 at %, respectively. By adding Ti to the alloy, the nucleation and growth of ?-Fe during the rapid quenching process can be minimized.
    Type: Grant
    Filed: July 19, 2002
    Date of Patent: March 24, 2009
    Assignee: Hitachi Metals, Ltd.
    Inventors: Toshio Miyoshi, Hirokazu Kanekiyo, Satoshi Hirosawa
  • Publication number: 20090032147
    Abstract: An R—Fe—B based rare-earth alloy powder with a mean particle size of less than about 20 ?m is provided and compacted to make a powder compact. Next, the powder compact is subjected to a heat treatment at a temperature of about 550° C. to less than about 1,000° C. within hydrogen gas, thereby producing hydrogenation and disproportionation reactions (HD processes). Then, the powder compact is subjected to another heat treatment at a temperature of about 550° C. to less than about 1,000° C. within either a vacuum or an inert atmosphere, thereby producing desorption and recombination reactions and obtaining a porous material including fine crystal grains, of which the density is about 60% to about 90% of their true density and which have an average crystal grain size of about 0.01 ?m to about 2 ?m (DR processes). Thereafter, the porous material is subjected to yet another heat treatment at a temperature of about 750° C. to less than about 1,000° C.
    Type: Application
    Filed: October 21, 2008
    Publication date: February 5, 2009
    Applicant: HITACHI METALS, LTD.
    Inventors: Noriyuki NOZAWA, Takeshi NISHIUCHI, Satoshi HIROSAWA, Tomohito MAKI
  • Patent number: 7297213
    Abstract: An iron-based rare earth alloy magnet has a composition represented by the general formula: (Fe1-mTm)100-x-y-zQxRyMz, where T is at least one element selected from the group consisting of Co and Ni; Q is at least one element selected from the group consisting of B and C; R is at least one rare earth element substantially excluding La and Ce; and M is at least one metal element selected from the group consisting of Ti, Zr and Hf and always includes Ti. In this formula, the mole fractions x, y, z and m meet the inequalities of: 10 at %<x?20 at %; 6 at %?y<10 at %; 0.1 at %?z?12 at %; and 0?m?0.5, respectively.
    Type: Grant
    Filed: December 24, 2003
    Date of Patent: November 20, 2007
    Assignee: Neomax Co., Ltd.
    Inventors: Hirokazu Kanekiyo, Toshio Miyoshi, Satoshi Hirosawa, Yasutaka Shigemoto, Yusuke Shioya
  • Patent number: 7261781
    Abstract: A nanocomposite magnet has a composition represented by (Fe1-mTm)100-x-y-z-nQxRyTizMn, where T is at least one of Co and Ni, Q is at least one of B and C, R is at least one rare earth element that always includes at least one of Nd and Pr and optionally includes Dy and/or Tb, and M is at least one element selected from the group consisting of Al, Si, V, Cr, Mn, Cu, Zn, Ga, Zr, Nb, Mo, Ag, Hf, Ta, W, Pt, Au and Pb. The mole fractions x, y, z, m and n satisfy 10 at %<x?20 at %, 6 at %?y<10 at %, 0.5 at %?z?12 at %, 0?m?0.5 and 0 at %?n?10 at %, respectively. The nanocomposite magnet has an oxygen content of at most about 1,500 ppm by mass.
    Type: Grant
    Filed: November 19, 2002
    Date of Patent: August 28, 2007
    Assignee: Neomax Co., Ltd.
    Inventors: Hirokazu Kanekiyo, Toshio Miyoshi, Satoshi Hirosawa
  • Publication number: 20070137732
    Abstract: A method of making a magnetic alloy material includes the steps of: preparing a melt of an alloy material having a predetermined composition; rapidly cooling and solidifying the melt to obtain a rapidly solidified alloy represented by: Fe100-a-b-cREaAbTMC where RE is at least one rare-earth element selected from La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er and Tm and including at least about 90 at % of La; A is at least one element selected from Al, Si, Ga, Ge and Sn; TM is at least one transition metal element selected from Sc, Ti, V, Cr, Mn, Co, Ni, Cu and Zn; and 5 at %?a?10 at 5%, 4.7 at% ?b?18 at % and 0 at %?c?9 at %; and producing a compound phase having an NaZn13-type crystal structure in at least about 70 vol % of the rapidly solidified alloy.
    Type: Application
    Filed: February 12, 2007
    Publication date: June 21, 2007
    Applicant: NEOMAX CO., LTD.
    Inventors: Ryosuke KOGURE, Hirokazu KANEKIYO, Takeshi NISHIUCHI, Satoshi HIROSAWA
  • Publication number: 20070131309
    Abstract: A nanocomposite magnet according to the present invention has a composition represented by the general formula: RxQyMz(Fe1?mTm)bal, where R is at least one rare-earth element, Q is at least one element selected from the group consisting of B and C, M is at least one metal element that is selected from the group consisting of Al, Si, Ti, V, Cr, Mn, Cu, Zn, Ga, Zr, Nb, Mo, Ag, Hf, Ta, W, Pt, Au and Pb and that always includes Ti, and T is at least one element selected from the group consisting of Co and Ni. The mole fractions x, y, z and m satisfy the inequalities of 6 at % ?x<10 at %, 10 at % ?y?17 at %, 0.5 at % ?z?6 at % and 0?m?0.5, respectively. The nanocomposite magnet includes a hard magnetic phase and a soft magnetic phase that are magnetically coupled together. The hard magnetic phase is made of an R2Fe14B-type compound, and the soft magnetic phase includes an ?-Fe phase and a crystalline phase with a Curie temperature of 610° C. to 700° C. (? phase) as its main phases.
    Type: Application
    Filed: December 6, 2004
    Publication date: June 14, 2007
    Applicant: NEOMAX CO., LTD.
    Inventors: Yasutaka Shigemoto, Satoshi Hirosawa, Toshio Miyoshi
  • Patent number: 7217328
    Abstract: A compound for a rare-earth bonded magnet includes a rare-earth alloy powder and a binder. The rare-earth alloy powder includes at least about 2 mass % of Ti-containing nanocomposite magnet powder particles with a composition represented by (Fe1-mTm)100-x-y-zQxRyMz, where T is Co and/or Ni; Q is B with or without C; R is at least one rare-earth element substantially excluding La and Ce; M is at least one metal element selected from Ti, Zr and Hf and always includes Ti; and 10<x?20 at %; 6?y<10 at %; 0.1?z?12 at %; and 0?m?0.5. The particles include at least two ferromagnetic crystalline phases, in which hard magnetic phases have an average crystal grain size of about 10 nm to about 200 nm, soft magnetic phases have an average crystal grain size of about 1 nm to about 100 nm; and the average crystal grain size of the soft magnetic phases is smaller than that of the hard magnetic phases.
    Type: Grant
    Filed: August 18, 2003
    Date of Patent: May 15, 2007
    Assignee: Neomax Co., Ltd.
    Inventors: Takeshi Nishiuchi, Hirokazu Kanekiyo, Satoshi Hirosawa, Toshio Miyoshi
  • Patent number: 7208097
    Abstract: An iron-based rare earth alloy nanocomposite magnet has a composition represented by (Fe1-mTm)100-x-y-zQxRyTiz, where T is Co and/or Ni, Q is B and/or C and R is rare earth element(s) including substantially no La or Ce. x, y, z and m satisfy 10 at %<x?17 at %, 7 at %?y<10 at %, 0.5 at %?z?6 at % and 0?m?0.5, respectively. The magnet includes crystal grains of an R2T14Q type compound having an average grain size of 20 nm to 200 nm and a ferromagnetic iron-based boride that exists in a grain boundary between the crystal grains of the R2T14Q type compound. The boride is dispersed in, or present in the form of a film over, the grain boundary to cover at least partially the surface of the crystal grains of the R2T14Q type compound.
    Type: Grant
    Filed: May 8, 2002
    Date of Patent: April 24, 2007
    Assignee: Neomax Co., Ltd.
    Inventors: Hirokazu Kanekiyo, Toshio Miyoshi, Satoshi Hirosawa