公开(公告)号：US09875765B2

公开(公告)日：2018-01-23

申请号：US15271359

申请日：2016-09-21

Applicant: SHOWA DENKO K.K.

Inventor： Koji Yukimatsu ,  Isao Murase ,  Kiminori Sugimoto ,  Tomoya Kobayashi

IPC: G11B5/73 ,  C22C21/04 ,  C22C21/08

CPC classification number: G11B5/7315 ,  C22C21/04 ,  C22C21/08

Abstract: A base for a magnetic recording medium includes, a substrate made of an Al alloy, and a film made of a NiP-based alloy and provided on the substrate. The Al alloy of the substrate includes Mg in a range of 0.2 mass % to 6 mass %, Si in a range of 3 mass % to 17 mass %, Zn in a range of 0.05 mass % to 2 mass %, and Sr in a range of 0.001 mass % to 1 mass %. An average grain diameter of Si grains in an alloy structure of the substrate is 2 μm or less. The film has a thickness of 10 μm or greater. The substrate has an outer diameter of 53 mm or greater, a thickness of 0.9 mm or less, and a Young's modulus of 79 GPa or higher.

公开(公告)号：US12134805B2

公开(公告)日：2024-11-05

申请号：US17603843

申请日：2020-03-11

Applicant: SHOWA DENKO K.K.

Inventor： Isao Murase

IPC: C22C21/06 ,  C22F1/04 ,  C23C14/06 ,  C23C16/30

Abstract: An aluminum alloy member forms a fluoride film thereon, which does not form a black dot-shaped bulged portion and, therefore, has excellent smoothness and excellent corrosion resistance against a corrosive gas, plasma, and others. An aluminum alloy member for forming a fluoride film thereon, consists of: Si: 0.01 mass % to 0.3 mass %; Mg: 0.5 mass % to 5.0 mass %; Fe: 0.05 mass % to 0.5 mass %; Cu: 0.5 mass % or less; Mn: 0.30 mass % or less; Cr: 0.30 mass % or less, and the balance being Al and inevitable impurities, wherein when an average major diameter of Fe-based crystallized products in the aluminum alloy member is “D” (μm), and an average crystalline particle diameter in the aluminum alloy member is “Y” (μm), a relational expression: Log10 Y

公开(公告)号：US10593359B2

公开(公告)日：2020-03-17

申请号：US15621319

申请日：2017-06-13

Applicant: SHOWA DENKO K.K.

Inventor： Isao Murase ,  Kiminori Sugimoto

IPC: G11B5/73 ,  G11B5/858 ,  G11B5/48

Abstract: A magnetic recording medium substrate is provided in which a NiP type plating film is formed on a surface of an aluminum alloy substrate that includes Si in a range of 9.5 mass % or more and 11.0 mass % or less, Mn in a rage of 0.45 mass % or more and 0.90 mass % or less, Zn in a range of 0.32 mass % or more and 0.38 mass % or less, Sr in a range of 0.01 mass % or more and 0.05 mass % or less. In the alloy structure of the aluminum alloy substrate, an average particle diameter of Si particles is 2 μm or less, the film thickness of the NiP type plating film is 7 μm or more. An outer diameter of the magnetic recording medium substrate is 53 mm or more, the thickness is 0.9 mm or less, and the Young's modulus is 79 GPa or more.

公开(公告)号：US12054811B2

公开(公告)日：2024-08-06

申请号：US17257677

申请日：2019-04-19

Applicant: SHOWA DENKO K.K.

Inventor： Isao Murase

IPC: C22C21/06 ,  C22F1/05 ,  C23C28/04

CPC classification number: C22C21/06 ,  C22F1/05 ,  C23C28/04

Abstract: Provided is an aluminum alloy member for forming a fluoride film thereon, the fluoride film being excellent in smoothness without occurrence of a black dot-shaped bulged portion and excellent in corrosion resistance against corrosive gas and plasma, etc. The aluminum alloy member for forming a fluoride film thereon 1 for use in a semiconductor producing apparatus consists of Si: 0.3 mass % to 0.8 mass %; Mg: 0.5 mass % to 5.0 mass %; Fe: 0.05 mass % to 0.5 mass %; Cu: 0 mass % or more and 0.5 mass % or less; Mn: 0 mass % or more and 0.30 mass % or less; Cr: 0 mass % or more and 0.30 mass % or less 0.5 mass % or less; and the balance being Al and inevitable impurities. When an average major diameter of a Fe-based crystallized product in the aluminum alloy member is D (μm), and an average crystalline particle diameter in the aluminum alloy member is Y (μm), a relation expression of log10 Y←0.320D+4.60 is satisfied. A fluoride film 2 is formed on at least a part of a surface of the aluminum alloy member 1 for forming a fluoride film thereon.

公开(公告)号：US10573342B2

公开(公告)日：2020-02-25

申请号：US15866831

申请日：2018-01-10

Applicant: SHOWA DENKO K.K.

Inventor： Isao Murase ,  Kiminori Sugimoto

IPC: G11B5/73 ,  G11B25/04

Abstract: A base for a magnetic recording medium, includes a substrate made of an Al alloy and having a surface, and a film made of a NiP-based alloy and plated on the surface of the substrate. The film has a thickness of 7 μm or greater, and a ratio E/ρ is 29 or greater, where E [GPa] denotes the Young's modulus of the substrate, and ρ [g/cm3] denotes a density of the substrate.