G&M Golden Mangetic Technology ( Shenzhen ) Co., LTD.
Tel:+86-755-86332949 Fax: +86-755-26406857
Address:Unit 603, block A huachuangda building, Baoan District, Shenzhen, Guangodng
G&M Golden Magnetic Technology (Hongkong ) Co.,Ltd.
Office Address:1101 Leader industry center, No.57-59 An pui wan Street, Fotan, Shatin, Hongkong
Factory Add:118 Liangtian Zone, Taimei town, Boluo disrict, huizhou city, guangdong province
In order to increase the Hc of the iron oxide magnetic powder, it has long been desired to use a method of adding cobalt thereto, and the most successful one has been a cobalt-coated magnetic powder. The method was first proposed by the United States in 1971. Cobalt can be divided into two types: γ-Fe2O3 is used as a raw material to disperse in water and coated with Co(OH)2 or cobalt ferrite CoxFe3-xO4. The latter's Hc can be about doubled. The Avi-lyn magnetic powder developed by Tokyo Electric Chemical Industry Co., Ltd. in Japan in 1973 belongs to this category. Its Hc is high and can vary within a certain range and the wear on the magnetic head is only 1/5 of that of chromium dioxide. The magnetic tape made of cobalt-coated magnetic powder is not only completely interchangeable with the chromium dioxide tape, but also has a color signal output level and a signal-to-noise ratio exceeding that of the chromium dioxide tape.
In recent years, hexagonal ferroelectrics (Hc>2000Oe) and other high-Hc permanent magnet materials have also been used as recording materials due to the special needs of high Hc replication master tapes, magnetic cards, and perpendicular recording for high Hc magnetic powders. And received attention. In 1982, a strontium ferrite single domain fine powder was developed by glass crystallization in Japan and made into a coated vertical magnetic tape.