公开(公告)号：US20230075546A1

公开(公告)日：2023-03-09

申请号：US17789685

申请日：2021-01-20

Applicant: Sony Group Corporation ,  (NATIONAL INSTITUTE OF ADVANCED INDUSTRIAL SCIENCE AND TECHNOLOGY)

Inventor： Takeshi TAKAHASHI ,  Katsunori MAESHIMA ,  Minoru YAMAGA ,  Masaru TERAKAWA ,  Natsuki ICHISE ,  Tomoe SATO ,  Takashi KATAGUCHI ,  Atsuya TOWATA ,  Kimihiro OZAKI ,  Akihiro MATSUMOTO

IPC: G11B5/706 ,  G11B5/714

Abstract: Provided is a magnetic recording medium that is able to achieve both an improvement in electromagnetic conversion characteristics and ensuring of high long-term reliability. The magnetic recording medium includes a magnetic layer and a base. The magnetic layer includes magnetic powders including ε-iron oxide. A ratio (Hrp/Hc) of residual coercivity (Hrp) measured in a perpendicular direction of the magnetic recording medium with use of a pulse magnetic field to perpendicular coercivity (Hc) of the magnetic recording medium is 2.0 or less. Saturation magnetization (Mst) per unit area of the magnetic recording medium is 4.5 mA or greater.

公开(公告)号：US20170304898A1

公开(公告)日：2017-10-26

申请号：US15517207

申请日：2015-10-02

Applicant: NATIONAL INSTITUTE OF ADVANCED INDUSTRIAL SCIENCE AND TECHNOLOGY

Inventor： Koji SHIMOJIMA ,  Ryouichi FURUSHIMA ,  Hiroyuki HOSOKAWA ,  Kiyotaka KATOU ,  Akihiro MATSUMOTO

IPC: B22F3/14 ,  C22C29/04 ,  B22F1/00

CPC classification number: B22F3/14 ,  B22F1/0059 ,  B22F2005/001 ,  B22F2201/02 ,  B22F2201/11 ,  B22F2201/20 ,  B22F2302/10 ,  B22F2302/15 ,  B22F2998/10 ,  C22C29/02 ,  C22C29/04 ,  C22C29/08 ,  C22C29/14 ,  C22C29/16 ,  B22F9/04

Abstract: Provided is a hard sintered body which exhibits excellent high temperature oxidation resistance and has a high hardness at a high temperature. In the hard sintered body, a binder phase is contained at from 8.8 to 34.4 mol % and the balance is composed of a hard phase and inevitable impurities. The binder phase contains iron aluminide containing FeAl as a main component and alumina that is dispersed in iron aluminide and has a particle size of 1 μm or less. The hard phase is composed of at least one kind selected from carbides, nitrides, carbonitrides and borides of Group 4 metals, Group 5 metals and Group 6 metals in the periodic table, and solid solutions of these. This hard sintered body is obtained by mixing and pulverizing a binding particle powder containing an iron aluminide powder composed of at least one kind selected from FeAl2, Fe2Al5 and FeAl3 and a hard particle powder composed of at least one kind selected from carbides, nitrides, carbonitrides and borides of Group 4 metals, Group 5 metals and Group 6 metals in the periodic table and then sintering a mixed powder thus obtained.