Hitachi Metals, Ltd.

Kabushiki Kaisha Toshiba

Makoto Ushijima

Ryo Goto

Fumio Nitanda

Manabu Toyoda

Tadafumi Tomitani

Masanobu Yamazaki

Yoshifumi Nagamoto

Yoshihiko Kuriyama

Shohei Takami

Tsutomu Shimonosono

Tomoko Ota

Yuuji Minemoto

Yasuyuki Azuma

Noriaki Uchida

Etsuo Yanagisawa

A superconducting magnet device for a single crystal pulling apparatus is arranged outside a pulling furnace containing a crucible for melting a single crystal material therein so as to apply a magnetic field to the melted single crystal material. The superconducting magnet device for a single crystal pulling apparatus includes a cryostat containing a superconducting coil therein, and a refrigerator port arranged on the outer circumferential surface of the cryostat and provided with a cryogenic refrigerator that cools the superconducting coil. The cryogenic refrigerator is provided in a region of the outer surface region of the cryostat at which the intensity of the magnetic field generated by the superconducting coil is weak.

Superconducting magnet device for single crystal pulling apparatus

A heat-treating furnace with a magnetic field comprising (a) a magnetic field-generating means constituted by an outer, ring-shaped, permanent magnet assembly comprising a plurality of permanent magnet segments combined with their magnetization directions oriented such that a magnetic flux flows in a diameter direction, and an inner, ring-shaped, permanent magnet assembly disposed inside the outer, ring-shaped, permanent magnet assembly and comprising a plurality of permanent magnet segments combined with their magnetization directions oriented such that a magnetic flux flows in a diameter direction; and (b) a heat treatment means disposed in a center hole of the inner, ring-shaped, permanent magnet assembly and comprising a cooling means, a heating means, and a heat-treating container containing heat-treating holder for holding a plurality of articles to be heat-treated in this order from outside, wherein an axial center of a magnetic field generated by the inner and outer ring-shaped, permanent magnet assemblies is substantially identical with an axial center of an article assembly in the heat-treating container.

Heat-treating furnace with magnetic field and heat treatment method using same

A flying-type composite magnetic head includes (a) a magnetic core constituted by a pair of core pieces bonded together by a first glass portion, at least one of opposing surfaces of the core pieces being formed with a thin magnetic metal layer; (b) a non-magnetic slider having a slit for receiving the magnetic core; and (c) a second glass portion for fixing the magnetic core in the slit; the first glass portion having a softening point lower than a first bonding temperature by 70.degree. C. or more and a yielding temperature higher than a second bonding temperature, and the second glass portion having a softening point lower than a second bonding temperature by 70.degree. C. or more. The first bonding temperature T.sub.1 (.degree.C.) for forming the first glass portion satisfies the following relation:

Method of producing a fly-type composite magnetic head with appropriate

A flying-type composite magnetic head includes (a) a magnetic core constituted by a pair of core pieces bonded together by a first glass portion, at least one of opposing surfaces of the core pieces being formed with a thin magnetic metal layer; (b) a non-magnetic slider having a slit for receiving the magnetic core; and (c) a second glass portion for fixing the magnetic core in the slit; the first glass portion having a softening point lower than a first bonding temperature by 70.degree. C. or more and a yielding temperature higher than a second bonding temperature, and the second glass portion having a softening point lower than a second bonding temperature by 70.degree. C. or more. The first bonding temperature T.sub.1 .degree.C.) for forming the first glass portion satisfies the following relation:

Flying-type composite magnetic head with appropriate bonding glasses and

A magnetic core for a flying-type composite magnetic head, including a pair of core pieces, a glass portion for bonding the core pieces, and a thin magnetic metal layer of Fe-Al-Si alloys formed on at least one of opposing surfaces of the core pieces. The thin magnetic metal layer extends by 10 .mu.m or more from an apex of a magnetic gap defined by the core pieces and has an inner end existing by 15 .mu.m or more inside an inner end of the bonding glass portion.

Magnetic core for flying-type composite magnetic head

A non-magnetic part bonded to a magnetic core portion made of Ni-Zn ferrite in a magnetic head assembly which is made of a ceramic material comprised of 30 to 50 volume % of TiO.sub.2 and 70 to 50 volume % of Ba.sub.2 Ti.sub.9 O.sub.20 and BaAl.sub.2 Ti.sub.5 O.sub.14 wherein the volume ratio of Ba.sub.2 Ti.sub.9 O.sub.20 to the total volume of Ba.sub.2 Ti.sub.9 O.sub.20 and BaAl.sub.2 Ti.sub.5 O.sub.14 is 0.05 to 0.5.

Non-magnetic part in magnetic head assembly

Improved precipitation hardening permanent magnetic alloys of Alnico 9 type having comparatively lower Co content of 28 - 30 weight percent and further contain 0.02 - 0.2% C, 0.1 - 1% S and 0.1 - 4.0% Nb together all by weight, and Nb to Ti ratio of the alloys satisfies the formula;

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Tokyo, Japan

Makoto Ushijima