公开(公告)号：JPH10139544A

公开(公告)日：1998-05-26

申请号：JP22927097

申请日：1997-08-26

Applicant: KOREA ELECTRONICS TELECOMM ,  KOREA TELECOMMUN

Inventor： PARK JUNG RAE ,  KIM TAE HONG ,  LEE SANG SUK ,  CHOI TAE GU

IPC: C04B35/00 ,  C04B35/26 ,  C04B35/40 ,  C04B35/50 ,  H01F1/34 ,  C04B35/495

Abstract: PROBLEM TO BE SOLVED: To provide a magnetic ceramic compsn. having proper saturation magnetization, a small half-width of ferrimagnetic resonance and a low temp. coefft. of saturation magnetization by using yttrium oxide, iron oxide, tin oxide, aluminum oxide and a calcium feeding source as essential components. SOLUTION: Yttrium oxide is mixed with iron oxide, the oxide, aluminum oxide and calcium carbonate or calcium oxide so as to give a compsn. represented by the formula Y3-x Cax/2 Snx/2 Fe5-y Aly O12 (where 0.1

公开(公告)号：FR2755128B1

公开(公告)日：1999-07-23

申请号：FR9704809

申请日：1997-04-18

Applicant: KOREA ELECTRONICS TELECOMM

Inventor： PARK JUNG RAE ,  KIM TAE HONG ,  LEE SANG SUK ,  CHOI TAE GU

IPC: C04B35/00 ,  C04B35/26 ,  C04B35/40 ,  C04B35/50 ,  H01F1/34 ,  C04B35/457 ,  C04B35/64 ,  H01F1/10

Abstract: A material for microwave band devices used by the general people and in industrial electronic apparatuses is disclosed. Particularly, a magnetic ceramic composition for use in microwave devices, a magnetic ceramics for use in microwave devices and a preparation method therefore are disclosed, in which the saturation magnetization can be easily controlled, and a low ferri-magnetic resonance half line width and an acceptable curie temperature are ensured. The magnetic ceramic composition for microwave devices includes yttrium oxide (Y2O3), iron oxide (Fe2O3), tin oxide (SnO2), aluminum oxide (Al2O3) and a calcium supply source. The magnetic ceramics for the microwave devices are manufactured by carrying out a forming and a sintering after mixing: yttrium oxide, iron oxide, tin oxide, aluminum oxide and calcium carbonate (or calcium oxide) based on a formula shown below. It has a saturation magnetization of 100-1,800 G at the normal temperature, a temperature coefficient for the saturation magnetization of 0.2%/ DEG C., and a ferri-magnetic resonance half line width of less than 60 Oe, Y3-xCax/2Snx/2Fe5-yAlyO12 where 0.1

公开(公告)号：FR2755128A1

公开(公告)日：1998-04-30

申请号：FR9704809

申请日：1997-04-18

Applicant: KOREA ELECTRONICS TELECOMM

Inventor： PARK JUNG RAE ,  KIM TAE HONG ,  LEE SANG SUK ,  CHOI TAE GU

IPC: C04B35/00 ,  C04B35/26 ,  C04B35/40 ,  C04B35/50 ,  H01F1/34 ,  C04B35/457 ,  C04B35/64 ,  H01F1/10

Abstract: A novel magnetic ceramic composition and a novel magnetic ceramic used in microwave devices and containing yttrium oxide, iron oxide, tin oxide, aluminium oxide and a calcium source (preferably the carbonate or oxide), are based on formula (I): Y3-xCax/2Snx/2Fe5-yAlyO12, where x = 0.1-1 and y = 0.1-1.5. Also claimed is a process for producing a magnetic ceramic for microwave devices involving: (a) mixing yttrium oxide, iron oxide, tin oxide, aluminium oxide and calcium carbonate or oxide to form a mixture based on the above formula (I); (b) drying and calcining at 1,100-1,200 deg C for 1-3 hrs. to form a calcined powder; (c) adding a binder and then moulding the powder; and (d) sintering at 1,300-1,500 deg C in air.