Title:
MAGNETIC DISK SUBSTRATE MADE OF ALUMINUM ALLOY AND METHOD OF MANUFACTURING THE SAME, AND MAGNETIC DISK
Document Type and Number:
Japanese Patent JP2019091515
Kind Code:
A
Abstract:
To provide a magnetic disk substrate made of aluminum alloy with less defects on a Ni-P plating surface and less swelling on the Ni-P plating surface, a method of manufacturing the same, and a magnetic disk using the same.SOLUTION: The present invention are a magnetic disk substrate made of aluminum alloy, a method of manufacturing the same, and a magnetic disk using the magnetic disk substrate made of the aluminum alloy, the magnetic disk substrate made of aluminum alloy is characterized in that an aluminum alloy base material made of aluminum alloy having a predetermined composition, and an electroless Ni-P plating layer formed on the surface of the same are comprised, and in the surface of the electroless Ni-P plating layer of the aluminum alloy base material, existence density of a chemical compound having a maximum diameter of 3-6 μm is equal to or less than 300 pieces/mm, and when opening diameter is (X)μm and depth is (Y)μm, 80 pieces/cm or more holes in which Y/X is 0.8-3.0 exist at a radial position.SELECTED DRAWING: Figure 1
Inventors:
MURATA TAKUYA
KITAWAKI KOTARO
YONEMITSU MAKOTO
HATAKEYAMA HIDEYUKI
NAKAYAMA KEN
FUJII YASUO
TODA SADAYUKI
KITAWAKI KOTARO
YONEMITSU MAKOTO
HATAKEYAMA HIDEYUKI
NAKAYAMA KEN
FUJII YASUO
TODA SADAYUKI
Application Number:
JP2017219470A
Publication Date:
June 13, 2019
Filing Date:
November 14, 2017
Export Citation:
Assignee:
UACJ CORP
FURUKAWA ELECTRIC CO LTD
FURUKAWA ELECTRIC CO LTD
International Classes:
G11B5/73; C22C21/06; C22F1/047; G11B5/82; G11B5/84
Attorney, Agent or Firm:
Megumi Yumoto