Hitachi Metals, Ltd.

Other

Nippondenso Co., Ltd.

Hitachi Metals, Ltd. and Denso Corporation

Tsutomu Inui

Hakaru Sasaki

Keizo Takeuchi

Rokuo Ichiyasu

Shinya Sugiura

Yoshitada Katayama

Yoshitaka Chiba

Toshiaki Terada

Shunichiro Matsumoto

Hideki Nakamura

Takashi Meguro

Shin-ichiro Yokoyama

Yoichi Mochida

Takayuki Shibata

Masaki Shimizu

Yoshihiro Tanimura

Shuichi Nakamura

Youzou Majima

Akira Kawakami

Hideya Yamada

Noriyuki Nakaoka

Hironori Nakanishi

Takeo Mizuguchi

Shun-ichiro Matsumoto

Jun Sunakawa

Composite magnetic member, process for producing the member and electromagnetic valve using the member

Provided is a composite magnetic member made of a single material combining a ferromagnetic portion and a non-magnetic portion in which the ferromagnetic portion has better soft magnetism than conventional members and the non-magnetic portion has the same stable characteristic as conventional members. A method of producing the ferromagnetic portion of the member and a method of forming the non-magnetic portion are also provided. The composite magnetic member is made of an Fe&mdash;Cr&mdash;C-base alloy steel containing 0.1 to 5.0 weight % Al and has a ferromagnetic portion with a maximum magnetic permeability of not less than 400 and a non-magnetic portion with a magnetic permeability of not more than 2. In this member the number of carbides with a grain size of not less than 0.1 &mgr;m is regulated to not more than 50 in an area of 100 &mgr;m,and the proportion of the number of carbides with a grain size of not less than 1.0 &mgr;m to the number of all carbides is controlled to not less than 15%.

Composite magnetic member, method of producing ferromagnetic portion of same, and method of forming non-magnetic portion of same

This is a composite magnetic member excellent in corrosion resistance having a chemical composition consisting essentially, by weight, of 0.30 to 0.80% C, more than 16.0% but not more than 25.0% Cr, 0.1 to 4.0% Ni, 0.1 to 0.06% N, at least one kind not more than 2.0% in total selected from the group consisting of Si, Mn and Al, and the balance Fe and impurities, and having a ferromagnetic portion and a non-magnetic portion.

Composite magnetic member excellent in corrosion resistance and method of producing the same

A bias material for magnetic markers is produced by plastic working to provide a strip form, which has a metal structure consisting of the iron-base matrix and a non-magnetic copper group metal phase in an amount of not less than a solubility limit thereof in an equilibrium state at a room temperature. The non-magnetic copper group metal phase is dispersed in the matrix so as to form a microstructural rod pattern. The bias material comprises preferably 3 to 35% wt % of a copper group metal. The magnetic marker is produced by combining the bias material and a magnetostriction element.

Bias material, magnetic marker and method of producing the bias material

A metallic member including not more than 0.6% C, 12 to 19% Cr, 6 to 12% Ni, not more than 2% Mn, not more than 2% Mo, not more than 1% Nb and the balance being Fe and inevitable impurities, where Hirayama's equivalent H eq=�Ni %!+1.05 �Mn %!+0.65 �Cr %!+0.35 �Si %!+12.6 �C %! is 20 to 23%; Nickel equivalent Ni eq=�Ni %!+30 �C %!+0.5 �Mn %! is 9 to 12%, and Chromium equivalent Cr eq=�Cr %!+�Mo %!+1.5 �Si %!+0.5 �Nb %! is 16 to 19, wherein % is by weight, is made to have at least one ferromagnetized part having a magnetic flux density B.sub.4000 of not less than 0.3 T and at least one non-magnetized part having a relative magnetic permeability .mu. of not more than 1.2 at a temperature of not less than -40.degree. C., as continuously and integrally formed. The non-magnetized part has crystal grain sizes of not more than 30 .mu.m. The metallic member is subjected to ferromagnetization and successive local non-magnetization of part or parts of the ferromagnetized member, and the thus obtained composite magnetic member is employed as a support member such as a sleeve in electromagnetic valves.

Composite magnetic member, process for producing the member and

A composite magnetic member formed of a single material having a ferromagnetic section with high soft magnetism and a non-magnetic or the like section with sufficiently low magnetic (feebly magnetized or non-magnetic) and sufficient low MS temperature and a process for producing the member are provided. A composite magnetic member made of a single material of martensitic stainless steel including Ni having two sections of a ferromagnetic section having maximum permeability not less than 200 and coercive force not more than 2000 A/m and a feebly magnetized section having permeability not more than 2 and MS temperature not more than -30.degree. C. A process for producing a composite magnetic member, comprising the steps of locally heating a single material of martensitic stainless steel having particular composition including Ni and having ferrite and carbide, at temperature of more than austenite transformation temperature, and rapidly quenching it so that austenite structure is formed in the heated and quenched section which structure has MS temperature not more than -30.degree. C.

Composite magnetic member and process for producing the member

A flat-shaped fine Fe-Ni alloy powder suitable for use as a magnetic shield coating material for cards or the like. The powder has a mean particle size of 0.1 to 30 .mu.m, a mean thickness not greater than 2 .mu.m and a coercive force not greater than 400 A/m. The flat-shaped fine powder is produced by preparing an Fe-Ni alloy powder of a composition which exhibits, in a bulk state, a saturated magnetostriction constant value falling within the range of .+-.15.times.10.sup.-6 and which contains, by weight, 70 to 83% Ni, 2 to 6% Mo, 3 to 6% Cu, 1 to 2% Mn, not more than 0.05% C and the balance Fe and incidental impurities, pulverizing the alloy powder by an attrition mill, and annealing the pulverized powder in a fluidized or moving state in a substantially non-oxidizing atmosphere.

Fe-Ni alloy fine powder of flat shape

A high-strength lead frame material consists, by weight, of 0.5 to 22% Co, 22 to 32.5% Ni, not more than 1.0% Mn, not more than 0.5% Si, at least one kind of 0.1 to 3.0% in total selected from the group consisting of Nb, Ti, Zr, Mo, V, W and Be, and the balance Fe and incidental impurities; the total content of Ni and Co being selected so that the content of Ni is in the range of 27 to 32.5% when the content of Co is less than 12% and so that 66%.ltoreq.2Ni+Co.ltoreq.74% is met when the content of Co is not less than 12%; the lead frame material having a duplex-phase structure composed of a reverse-transformed austenite phase (which can involve a residual austenite phase) and a martensite phase; and the austenite phase being not less than 50%.

High-strength lead frame material and method of producing same

A flat-shaped fine Fe-Ni alloy powder suitable for use as a magnetic shield coating material for cards or the like. The power has a mean particle size of 0.1 to 30 .mu.m, a mean thickness not greater than 2 .mu.m and a coercive force not greater than 400 A/m. The flat-shaped fine powder is produced by preparing an Fe-Ni alloy powder of a composition which exhibits, in a bulk state, a saturated magnetostriction constant value falling within the range of .+-.15.times.10.sup.-6 and which contains, by weight, 70 to 83% Ni, 2 to 6% Mo, 3 to 6% Cu, 1 to 2% Mn, not more than 0.05% C and the balance Fe and incidental impurities, pulverizing the alloy powder by an attrition mill, and annealing the pulverized powder in a fluidized or moving state in a substantially non-oxidizing atmosphere.

A rare earth metal-iron group metal target for a magneto-optical disk is produced by mixing power (a) produced by the rapid quenching treatment of an alloy composed of at least one rare earth metal and at least one iron group metal in a composition range which permits the formation of an eutectic structure, with powder (b) from at least one iron group metal in an amount necessary for meeting the composition requirements of the target; and subjecting the resulting mixture to pressure sintering in vacuum or in an inert gas atmosphere at a temperature lower than a liquid phase-appearing temperature of the mixture to produce a rare earth metal-iron group metal intermetallic bonding layer betwen the particles.

Rare earth metal-iron group metal target, alloy powder therefor and

A rare earth metal-iron group metal target for a magneto-optical disk is produced by mixing powder (a) produced by the rapid quenching treatment of an alloy composed of at least one rare earth metal and at least one iron group metal in a composition range which permits the formation of an eutectic structure, with powder (b) from at least one iron group metal in an amount necessary for meeting the composition requirements of the target; and subjecting the resulting mixture to pressure sintering in vacuum or in an inert gas atmosphere at a temperature lower than a liquid phase-appearing temperature of the mixture to produce a rare earth metal-iron group metal intermetallic bonding layer between the particles.

A sintered target member consisting essentially of 50-75 weight % of Co, 3-12 weight % of Cr and balance substantially Ni, which has a structure comprising dispersion phases consisting essentially of one or more elements constituting the target member and having a maximum permeability of 50 or less. This target member is produced by mixing metal or alloy powders corresponding to low-permeability dispersion phases, charging the resulting mixture into a metal container; sealing the metal container under reduced pressure; sintering it at a temperature of 900.degree.-1300.degree. C. and pressure of 500 atm or more; and removing the metal container from the resulting sintered body.

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Yonago, Japan

Tsutomu Inui