The Furukawa Electric Co., Ltd.

Uacj Corporation

Dowa Electronics Materials Co., Ltd.

Dowa Mining Co., Ltd.

Nagoya Institute of Technology

Sumitomo Mitsui Construction Co., Ltd.

Ryo Sakamoto

Kotaro Kitawaki

Hideyuki Hatakeyama

Makoto Yonemitsu

Takuya Murata

Takashi Nakayama

Yasuo Fujii

Wataru Kumagai

Tomohiko Shibata

Hiroki Ota

Tetsuya Ikuta

Sadayuki Toda

Masatoshi Iwata

Jo Shimizu

Yu Matsui

Daisuke Hino

Tsuneo Ito

Yoshiyuki Kobayashi

Toshihiro Nakamura

Hiroyuki Ikeda

Ryuichi Toba

Yu Igarashi

Naoki Kitamura

Fumihiro Sato

Kiyoshi Araki

Shinpei Todo

Takashi Egawa

Ryohei Yamada

Toshiya Kitamura

Taku Matsuda

Makiko Yanagisawa

Keisuke Kamiya

Takashi Onoue

Akio Kasuga

Susumu Tsujikawa

Yasuhiko Niitsu

Noriya Ishida

The present invention aims at providing a composition containing aggregate, binder, and water that can achieve a higher degree of both flowability in the fresh state and a limitation of autogenous shrinkage. A composition of the present invention contains binder, aggregate, and water, wherein the aggregate contains: small-diameter aggregate classified into particle diameters of 300 μm or more and less than 1.18 mm; medium-diameter aggregate classified into particle diameters of 1.18 mm or more and less than 4.75 mm; and large-diameter aggregate classified into particle diameters of 4.75 mm or more and 5 mm or less; wherein a ratio of volume of water to a sum of volume of the binder and volume of aggregate having particle diameters of 5 mm or less is 15% or more and 26% or less, and the small-diameter aggregate, the medium-diameter aggregate, and the large-diameter aggregate each have a BET specific surface area of 0.4 (m/g) or less.

Composition containing aggregate, binder, and water

An aluminum alloy substrate for a magnetic disc is made of an aluminum alloy, containing Fe: 1.80 mass % or less, Mn: 0.70 mass % or less, Ni: 2.50 mass % or less, Si: 2.50 mass % or less, Cu: 1.00 mass % or less, Zn: 0.48 mass % or less and Mg: 1.00 to 3.50 mass %, wherein a total content of Fe, Mn and Ni is 1.60 to 4.50 mass % and a mass ratio of Cu/Zn is 0.01 to 0.35 or 6.00 to 50.00, with a balance being Al and inevitable impurities.

Aluminum alloy substrate for magnetic disc and magnetic disc

An aluminum alloy disc blank for a magnetic disc made of an aluminum alloy containing Fe: 0.005 to 1.800 mass % with the balance being Al and inevitable impurities, wherein a flatness change of the aluminum alloy disc blank for a magnetic disc when the aluminum alloy disc blank for a magnetic disc is held in the atmosphere at 50° C. or lower for 336 hours is 2.0 μm or less.

Aluminum alloy disc blank for magnetic disc and magnetic disc

An example thin substrate built-in hard disk drive includes a magnetic disk in a disk shape having a through-hole at the center, a spindle motor inserted into the through-hole of the magnetic disk and co-rotatably supporting the magnetic disk, and a base plate made of an aluminum alloy and supporting the spindle motor. The base plate has a metallographic structure in which a perimeter of a second phase particle having a longest diameter of 10 μm or more is 3 mm/mmor more, and the number of second phase particles having a longest diameter of 500 μm or more is 0 particles/mm.

Thin substrate built-in hard disk drive and base plate member for thin substrate built-in hard disk drive

There are provided: an aluminum alloy substrate for a magnetic disk, the aluminum alloy substrate including an aluminum alloy including 0.4 to 3.0 mass % of Fe and the balance of Al and unavoidable impurities, in which second phase particles having a longest diameter of 0.5 &#x3bc;m or more and less than 2.0 &#x3bc;m are dispersed at a distribution density of 5000 particles/mmor more; a method for producing the same; and a magnetic disk using the aluminum alloy substrate for a magnetic disk.

Aluminum alloy substrate for magnetic disks, method for producing same, and magnetic disk using said aluminum alloy substrate for magnetic disks

An aluminum alloy substrate for a magnetic disk including an aluminum alloy containing 0.1 to 3.0 mass % of Fe, 0.005 to 1.000 mass % of Cu, and 0.005 to 1.000 mass % of Zn, with a balance of Al and inevitable impurities, wherein in an outer peripheral surface thereof, the number of holes having maximum diameters of 10 &#x3bc;m or more is 200/mmor less, an aluminum alloy base disk for a magnetic disk and a magnetic disk, using the aluminum alloy substrate, and methods for manufacturing these.

Aluminum alloy substrate for magnetic disk and method for manufacturing same, aluminum alloy base disk for magnetic disk and method for manufacturing same, and magnetic disk and method for manufacturing the same

An aluminum alloy sheet for a magnetic disk includes an aluminum alloy comprising 0.10 to 3.00 mass % (hereafter simply '%') of Fe, 0.1 to 3.0% of Mn, 0.003 to 1.000% of Cu, and 0.005 to 1.000 s % of Zn, wherein second phase particles having a maximum diameter of 100 &#x3bc;m or more and 300 &#x3bc;m or less are dispersed at a distribution density of 50 particles/mmor less in a region (A) occupying 25% or less of a sheet thickness from a sheet thickness center plane to opposite surfaces of the sheet, second phase particles having a maximum diameter of 100 &#x3bc;m or more and 300 &#x3bc;m or less are 0 particles/mmin a region (C) that is obtained by excluding the region (A) from a region (B) occupying 50% or less of the sheet thickness from the sheet thickness center plane to the opposite surfaces of the sheet, and the amount of Mn solid solution is 0.03 mass % or more.

Aluminum alloy sheet for magnetic disk and production method therefor, and magnetic disk using said aluminum alloy sheet for magnetic disk

An aluminum alloy sheet for a magnetic disk, a method for manufacturing same, and a magnetic disk using same. The aluminum alloy sheet is made of an aluminum alloy comprising 0.10 to 3.00 mass % of Fe, 0.003 to 1.000 mass % of Cu, and 0.005 to 1.000 mass % of Zn, with a balance of Al and unavoidable impurities, wherein a value obtained by dividing a difference in an area ratio (%) of second phase particles between a region (A) and a region (B) by an average value of area ratios (%) of second phase particles in the regions (A) and (B) is 0.05 or less, the region (A) being a region from a sheet thickness center plane to a front surface of the sheet, and the region (B) being a region from the sheet thickness center plane to a rear surface of the plate.

A magnetic disk substrate is composed of an aluminum alloy substrate, a base plating layer on a surface of the aluminum alloy substrate, and a boundary region between the aluminum alloy substrate and the base plating layer. The boundary region includes a specific boundary region (D(1)) having Al emission intensities equal to 50% to 84% of an average Al emission intensity in an interior region of the aluminum alloy substrate in glow discharge optical emission spectroscopy in the depthwise direction from the surface of the magnetic disk substrate. The specific boundary region (D(1)) has a maximum Fe emission intensity (I(1)) higher than an average Fe emission intensity (I(1)) in the interior region of the aluminum alloy substrate in the glow discharge optical emission spectroscopy.

Magnetic disk substrate, method for manufacturing same and magnetic disk

Provided are a magnetic disk and a method of fabricating the magnetic disk. The magnetic disk includes an aluminum alloy plate fabricated by a process involving a CC method and a compound removal process, and an electroless Ni&#x2014;P plating layer disposed on the surface of the plate. The aluminum alloy plate is composed of an aluminum alloy containing 0.4 to 3.0 mass % (hereinafter abbreviated simply as '%') of Fe, 0.1% to 3.0% of Mn, 0.005% to 1.000% of Cu, 0.005% to 1.000% of Zn, with a balance of Al and unavoidable impurities. In the magnetic disk, the maximum amplitude of waviness in a wavelength range of 0.4 to 5.0 mm is 5 nm or less, and the maximum amplitude of waviness in a wavelength range of 0.08 to 0.45 mm is 1.5 nm or less.

Magnetic disc, aluminum alloy substrate for magnetic disc, and production method for aluminum alloy substrate

Provided is an aluminum alloy substrate for a magnetic disk that includes an aluminum alloy containing 0.4 to 3.0 mass % (hereinafter abbreviated as '%') of Fe, 0.005% to 1.000% of Cu, and 0.005% to 1.000% of Zn, with a balance of Al and unavoidable impurities. This substrate has a ratio A/B of 0.70 or more, where A indicates a distribution density of Al&#x2014;Fe intermetallic compound particles having maximum diameters of 10 &#x3bc;m or more and less than 16 &#x3bc;m, and B indicates a distribution density of Al&#x2014;Fe intermetallic compound particles having maximum diameters of 10 &#x3bc;m or more. The distribution density of Al&#x2014;Fe intermetallic compound particles having maximum diameters of 40 &#x3bc;m or more is at most one per square millimeter. Also provided are a method of fabricating this aluminum alloy substrate for a magnetic disk and a magnetic disk composed of the aluminum alloy substrate for a magnetic disk.

Aluminum-alloy substrate for magnetic disk, method for manufacturing same and magnetic disk employing said aluminum-alloy substrate for magnetic disk

There are provided: an aluminum alloy magnetic disk substrate including: an aluminum alloy base material including an aluminum alloy containing 0.4 to 3.0 mass % (hereinafter, simply referred to as '%') of Fe, 0.1 to 3.0% of Mn, 0.005 to 1.000% of Cu, and 0.005 to 1.000% of Zn, with the balance of Al and unavoidable impurities; and an electroless Ni&#x2014;P plated layer formed on a surface of the aluminum alloy base material, in which the peak value (BLEI) of Fe emission intensity at an interface between the electroless Ni&#x2014;P plated layer and the aluminum alloy base material, as determined by a glow discharge optical emission spectrometry device, is lower than Fe emission intensity (AlEI) in the interior of the aluminum alloy base material, as determined by the glow discharge optical emission spectrometry device; and a method for producing the aluminum alloy magnetic disk substrate.

Aluminum alloy magnetic disk substrate and method for producing same

Light emitting diode chip

An epitaxial substrate for electronic devices, in which current flows in a lateral direction and of which warpage configuration is properly controlled, and a method of producing the same. The epitaxial substrate for electronic devices is produced by forming a bonded substrate by bonding a low-resistance Si single crystal substrate and a high-resistance Si single crystal substrate together; forming a buffer as an insulating layer on a surface of the bonded substrate on the high-resistance Si single crystal substrate side; and producing an epitaxial substrate by epitaxially growing a plurality of III-nitride layers on the buffer to form a main laminate. The resistivity of the low-resistance Si single crystal substrate is 100 &#x3a9;&#xb7;cm or less, and the resistivity of the high-resistance Si single crystal substrate is 1000 &#x3a9;&#xb7;cm or more.

Epitaxial substrate for electronic device comprising a high resistance single crystal substrate on a low resistance single crystal substrate, and method of manufacturing

To provide an epitaxial substrate for electronic devices, in which current flows in a lateral direction, which enables accurate measurement of the sheet resistance of HEMTs without contact, and to provide a method of efficiently producing the epitaxial substrate for electronic devices, the method characteristically includes the steps of forming a barrier layer against impurity diffusion on one surface of a high-resistance Si-single crystal substrate, forming a buffer as an insulating layer on the other surface of the high-resistance Si-single crystal substrate, producing an epitaxial substrate by epitaxially growing a plurality of III-nitride layers on the buffer to form a main laminate, and measuring resistance of the main laminate of the epitaxial substrate without contact.

Epitaxial substrate for electronic device, in which current flows in lateral direction and method of producing the same

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Tokyo, Japan

Ryo Sakamoto