Hitachi Metals, Ltd.

Yoshio Bizen

Shunsuke Arakawa

Jun Sunakawa

Yoshihito Yoshizawa

Michihiro Nagao

Kiyotaka Yamauchi

Shin Nakajima

Hajime Itagaki

Toshikazu Nishiyama

Takashi Meguro

Shigekazu Suwabe

Hiroshi Shibasaki

Takayuki Motegi

Daichi Azuma

Setsuo Mishima

The invention provides a method of producing an amorphous alloy ribbon, the method including a step of producing an amorphous alloy ribbon by discharging a molten alloy through a rectangular opening of a molten metal nozzle having a molten metal flow channel along which the molten alloy flows, the opening being an end of the molten metal flow channel, onto a surface of a rotating chill roll, in which, among wall surfaces of the molten metal flow channel, a maximum height Rz(t) of a surface t, which is a wall surface parallel to a flow direction of the molten alloy and to a short side direction of the opening, is 10.5 &#x3bc;m or less.

Amorphous alloy ribbon and method of producing the same

A resonator for use in a marker in an electronic article surveillance system having an amorphous alloy ribbon having a width of 7 mm or less and a thickness of 18 &#x3bc;m to 23 &#x3bc;m. The amorphous alloy ribbon preferably has an average surface roughness Ra of 0.45 &#x3bc;m or less.

Resonator for use in electronic article surveillance systems

An amorphous alloy ribbon free from embrittlement and crystallization and having excellent surface conditions and shape in edge portions is produced by (a) preparing an alloy melt having a composition comprising 13 atomic % or less of B and 15 atomic % or less of at least one selected from the group consisting of transition elements of Groups 4A, 5A and 6A, the balance being substantially Fe; (b) ejecting the alloy melt at a temperature from the melting point of the alloy &plus;50&deg; C. to the melting point of the alloy &plus;250&deg; C. through a nozzle onto the cooling roll rotating at a peripheral speed of 35 m/second or less, a distance between a tip end of the nozzle and the cooling roll being 200 &mgr;m or less; (c) starting to supply a gas based on CO to the alloy melt after the surface temperature of the cooling roll has become substantially constant; and (d) grinding the cooling roll while supplying the gas based on CO .

Method for producing amorphous alloy ribbon, and method for producing nano-crystalline alloy ribbon with same

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

The method for producing a mother alloy for an iron-based amorphous alloy has the steps of (a) melting raw materials for elements constituting the amorphous alloy together with at least one oxide of an element constituting the amorphous alloy, the raw materials containing aluminum as an inevitable impurity, and the oxide having a smaller standard free energy of formation than that of Al O in an absolute value; and (b) removing the resultant Al O from the melt, thereby reducing the content of aluminum to 50 ppm or less in the melt.

Method for producing mother alloys for iron-based amorphous alloys

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 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

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

There is provided according to the present invention a magnetic alloy with ultrafine crystal grains having a composition represented by the general formula:

Magnetic alloy with ultrafine crystal grains and method of producing same

A magnetic alloy with ultrafine crystal grains having a composition represented by the general formula:

Growing community of inventors

Shimane-ken, Japan

Yoshio Bizen