Title:
PLASTIC-BONDED MAGNET
Document Type and Number:
WIPO Patent Application WO/1990/001779
Kind Code:
A1
Abstract:
A plastic-bonded magnet having high-energy magnetic properties which ordinary ferrite plastic magnets do not possess can be obtained according to the present invention by mixing oxide type strontium ferrite magnet pellets with easily oxidizable rare earth element type Nd-Fe-B magnet pellets or the like. The magnetic energy can be controlled by selecting the compounding ratio of said oxide type magnet pellets to said rare earth element type magnet pellets. The magnet can be obtained by separately subjecting the oxide type magnet powder and the rare earth element type magnet powder to coupling treatment such as silane coupling treatment to surround them with matrix plastics, then mixing them and molding the resulting mixture. This plastic magnet can be produced relatively inexpensively in spite of its high energy. In addition, mixing of the oxide type magnet powder with the rare earth element type magnet powder enables the absolute value of the negative magnetic temperature coefficient of the ferrite magnet to be reduced to 0 due to mutual compensation of respective magnetic temperature coefficients and, as the compounding ratio of the rare earth element type magnet is increased, the coefficient becomes positive. Thus the magnetic temperature coefficient can be controlled by changing the compounding ratio of the oxide type plastic magnet pellets to the rare earth element type plastic magnet pellets. Furthermore, the above-described surface treatment of magnetic powders serves to increase binding force to the matrix plastic to obtain the effect of preventing rare earth magnetic powder from rusting and improve the mechanical strength of the magnet itself.
More Like This:
| JPS6364304 | COMPOSITION FOR PLASTIC MAGNET |
| JPH02228539 | EVALUATION OF WETTABILITY OF MAGNETIC POWDER |
Inventors:
MATSUYAMA YOSHIHIKO (JP)
Application Number:
PCT/JP1989/000725
Publication Date:
February 22, 1990
Filing Date:
July 20, 1989
Export Citation:
Assignee:
KANEX YK (JP)
International Classes:
H01F1/032; H01F1/057; H01F1/09; H02K1/02; H02K15/03; (IPC1-7): H01F1/02; H02K21/06
Foreign References:
| JPS62257703A | 1987-11-10 | |||
| JPS60223095A | 1985-11-07 | |||
| JPH06362842A |
Other References:
See also references of EP 0381772A4
Download PDF: