Hitachi Metals, Ltd.

Shunsuke Arakawa

Yoshihito Yoshizawa

Yoshio Bizen

Shin Nakajima

Kiyotaka Yamauchi

Jun Sunakawa

Noriyoshi Hirao

Tooru Abe

Michihiro Nagao

Takashi Meguro

Yoshizo Sawada

Hiroya Suzuki

Hideaki Shimizu

Akira Yamataka

Katsuhisa Sugimoto

Kunio Shitori

The present invention provides a method for producing a Fe-based amorphous alloy ribbon comprising the steps of: ejecting a molten Fe-based alloy containing 10 atomic % or less of B onto a cooling roll to solidify the molten Fe-based alloy; and peeling the solidified Fe-based alloy from the cooling roll when the solidified Fe-based alloy has a temperature of 100 to 300&deg; C. A Fe-based amorphous alloy ribbon having no crystalline phase is stably, continuously produced without breakage by this method.

Methods for producing iron-based amorphous alloy ribbon and nanocrystalline material

A soft magnetic alloy strip is manufactured by a single roll method. The soft magnetic alloy strip is 0.2&times;d mm or less (, which &ldquo;d&rdquo; is a width of the strip,) in warpage in the widthwise direction of the strip, and has a continuous, long length not less than 50 m, in which a width of an air pockets occurring on a roll contact face is not more than 35 &mgr;m, a length of the air pockets is not more than 150 &mgr;m, and the centerline average roughness Ra of the roll contact face is not more than 0.5 &mgr;m.

Soft magnetic alloy strip, magnetic member using the same, and manufacturing method thereof

A method for winding a rapidly quenched thin metal ribbon has the steps of (1) ejecting a molten metal onto a rotating cooling roll to rapidly solidify the molten metal to form a thin metal ribbon, (2) peeling the thin metal ribbon from the cooling roll to let the thin metal ribbon to freely move from the cooling roll, and (3) bringing a rotating winding roll having an adhesive thereon into contact with the freely moving thin metal ribbon at an intermediate point thereof, so that the thin metal ribbon is wound around the winding roll with an excess portion of the thin metal ribbon forward of the intermediate point cut off.

Method for winding rapidly quenched thin ribbon, apparatus for producing rapidly quenched thin ribbon, and rapidly quenched thin ribbon coil

There is provided a high-performance magnetic core with a high &mgr;&prime;Qf-value for an RF accelerating. The strip wound magnetic core has a thin strip of nanocrystalline soft magnetic alloy, whose bcc solid solution with an average grain size less than 100 nm has a volume fraction more than 50% of the whole structure of the alloy, and around which an interlayer insulation film at least on one side thereof. A gap is formed in at least a part of a magnetic path of the magnetic core. Stack cores formed by arranging in series a plurality of the magnetic cores are oppositely installed via a high-voltage gap, making it possible to provide an excellent RF accelerating cavity.

Magnetic core for RF accelerating cavity and the cavity

A miniaturized transformer including (a) a planer or rod-shaped magnetic core having a height of 3 mm or less and constituted by a laminate of thin ribbons each having a thickness of 30 .mu.m or less, each thin ribbon being made of a nanocrystalline soft magnetic alloy having a structure at least partly occupied by crystal grains having an average crystal grain size of 100 nm or less, or an amorphous soft magnetic alloy, (b) at least one primary winding provided around the magnetic core, and (c) at least one secondary winding provided around the magnetic core.

Miniaturized transformer and inverter circuit and discharge tube glow

A nanocrystalline alloy wherein at least 50 volume % of an alloy structure consists of a crystal grain mainly comprising bcc-phase having a grain size of 50 nm or less, a saturation magnetic flux density of the alloy is 1 T or more, a remanent flux density of the alloy is 0.4 T or less, and an Fe--B compound phase is partially formed in the alloy. The nanocrystalline alloy produced by heat treatment without applying any magnetic field shows pulse attenuation characteristics comparable to or more excellent than those of a nanocrystalline alloy obtained by heat treatment in a magnetic field.

Nanocrystalline alloy having excellent pulse attenuation

A pulse transformer comprising a magnetic core formed of a thin strip of nanocrystalline soft magnetic alloy in which fine nanocrystalline grains having a grain size of not more than 50 nm occupy at least 50 volume % of the structure, characterized in that the AC relative initial magnetic permeability at -20.degree. C. and 50.degree. C. is not less than 50000.

Magnetic core for pulse transformer and pulse transformer made thereof

There is provided an alloy with ultrafine crystal grains excellent in corrosion resistance, at least 50% of the alloy structure being occupied by ultrafine crystal grains, the alloy having a surface layer containing hydroxide components in a total proportion of 65% or more based on oxide components.

Alloy with ultrafine crystal grains excellent in corrosion resistance

An active filter circuit including a smoothing filter including a choke coil comprising a magnetic core composed of a nanocrystalline alloy and having a magnetic gap in at least one portion thereof and at least one conductive wire wound around the magnetic core, the nanocrystalline alloy having a composition of 0.1-3 atomic % of at least one element selected from the group consisting of Cu and Au, 1-7 atomic % of at least one element selected from the group consisting of Ti, Zr, Hf, V, Nb, Ta, Mo and W, 10-17 atomic % of Si, and 4-10 atomic % of B, the balance being substantially Fe and inevitable impurities.

Active filter circuit and power supply apparatus including same

A method for producing a nanocrystalline alloy wherein an amorphous alloy is heat-treated by keeping the temperature at a first heat treatment temperature higher than the crystallization temperature of the amorphous alloy for 0 to less than 5 minutes, and is cooled to room temperature at a cooling rate of 20.degree. C./min or more at least until the temperature falls to 400.degree. C. The amorphous alloy subjected to the first heat treatment may be further heat-treated at a second heat treatment temperature not higher than 500.degree. C. and lower than the first heat treatment temperature while applying a magnetic field. The nanocrystalline alloy produced by the method of the invention has a extremely high specific initial permeability as compared with the conventional nanocrystalline alloy, and is suitable for use in magnetic core of transformers, choke coils, etc.

Method of producing nanocrystalline alloy having high permeability

A magnetic core element for use in a thin antenna. The magnetic core element has a thickness of 25 .mu.m or less and is made of a particular amorphous alloy strip or a particular nano-crystalline alloy strip. A thin antenna having a laminated magnetic core made of the magnetic core elements is highly resistant to deformation and has a high Q-value.

Magnetic core element for antenna, thin-film antenna, and card equipped

A wound magnetic core constituted by (a) a thin ribbon made of a fine crystalline, soft magnetic Fe-base alloy having the composition represented by the general formula:

Method for making wound magnetic core

Wound magnetic core

A magnetic device for high-voltage pulse generating apparatuses including (a) at least one cylindrical conductor for defining a cavity, the cylindrical conductor being provided with input and output terminals and an inlet and an outlet for a coolant; (b) at least one sealing member fixed to the cylindrical conductor; (c) a plurality of wound magnetic cores each composed of a magnetic ribbon laminated with an insulating layer, the wound magnetic cores being fixed to the cylindrical conductor with such an interval as to provide a certain space between the adjacent wound magnetic cores; and (d) an outer ring member disposed between each of the magnetic cores and the cylindrical conductor and having at least one path for permitting the coolant to flow therethrough, whereby the coolant flows in a radial or circumferential direction of each wound magnetic core in each space between the adjacent wound magnetic cores.

Magnetic device for high-voltage pulse generating apparatuses

A method of manufacturing an amorphous metal sheet or ribbon which comprises extruding a molten metal from an orifice of a nozzle and directing the extruded molten metal onto a moving chill surface to rapidly cool and solidify the metal thereby forming said sheet or ribbon; said orifice being a rectangular slit defined by side walls and a front lip and a back lip arranged in front and behind the slit in the direction of movement of the chill surface below said nozzle; said chill surface moving a speed of 10 m/sec to 50 m/sec and being spaced from the front lip by a gap length of from 100 .mu.m to 600 .mu.m and the width W.sub.F of the front lip measured in the direction of movement of the chill surface being represented by the relationship W.sub.F .ltoreq.W, wherein W represent the width the slot in the nozzle.

Growing community of inventors

Kumagaya, Japan

Shunsuke Arakawa