JPS63152111A - Permanent magnet manufacturing method - Google Patents

Abstract

PURPOSE:To manufacture the permanent magnet having both excellent magnetic characteristics and corrosion-resisting property by a method wherein rareearth- iron magnetic powder is coupling-treated using silane or titanate coupling agent, and it is molded after mixing with resin. CONSTITUTION:The rareearth-iron magnetic powder manufactured by performing a superquenching treatment is coupling-treated using a titanate coupling agent. In this case, when the coupling treatment is going to be performed, various kinds of silane coupling agents and titanate coupling agents are properly diluted using the solvent such as alcohol, toluene and the like, and it is dried up. After the above-mentioned material has been dried up, the coupling-treated magnetic powder is mixed with thermosetting resin and thermoplastic resin, and the molded body of the prescribed shape is formed by performing a compression molding or an injection molding operation. Then, a curing treatment is performed on the molded body as occasion demands. As the material magnetic powder is coupling-treated using a silane or titanate coupling agent, the obtained permanent magnet has excellent corrosion-resisting property, and the deterioration in magnetic characteristics caused by the generation of corrosion can be prevented.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) This invention is applicable to home appliances, audio products, ff'? The present invention relates to a method for manufacturing permanent magnets that can be used in a wide range of applications using permanent magnets, such as instrument parts, automobile parts, and precision instruments.

[Conventional technology]

In recent years, rare earth magnets have been developed as magnets with even better magnetic properties than conventional alnico magnets and rare earth cobalt magnets.
Iron-based permanent magnets are attracting attention.

(Problems to be solved by the invention) Representative examples of this cold earth-iron permanent magnet include:
There are permanent magnets based on Nd-Fe-B. This Nd-Fe-
Although B-based permanent magnets have extremely excellent magnetic properties, they have the drawback of not having very good eating properties.

For example, the corrosion resistance of Nb-Fe-B permanent magnets manufactured by the sintering method is not very good, and the ultra-quenched Nd-
Even in permanent magnets that are compression molded or injection molded using Fe-B powder and mixed with resin, there is a problem in that corrosion resistance is not necessarily good in a severely corrosive environment.

(Objective of the Invention) This invention was made by focusing on the above-mentioned conventional problems, and it is possible to produce a permanent magnet that has good magnetic properties and excellent corrosion resistance. The purpose is to provide a manufacturing method.

[Structure of the Invention] The method for producing a permanent magnet according to the present invention involves coupling rare earth-iron magnet powder with a silane-based or titanate-based coupling agent, and then mixing it with a resin and molding it. In addition to having good properties, it is characterized by improved corrosion resistance.

As the rare earth-iron magnet powder to which this invention is applied, it is particularly desirable to use magnet powder produced by an ultra-quenching method from the viewpoint of improving magnetic properties and corrosion resistance.

In addition, as rare earth-iron magnet powder, R1-ct-
β-A is represented by FecxxβMy, R is one or more rare earth elements, Fe is iron, and X is B, C, N, Si.
, one or more types of P, M is Ti, Zr, Hf, V
, Nb, Ta.

One or more of Cr, Mo, W, All, and Zn.

It is desirable to apply it to those where 0.60≦α≦0.85゜0<β≦0.15, O≦γ≦o, oi, among others, Nd-
It is desirable to apply this method to Fe-B-based magnet powder because it can improve the corrosion resistance of permanent magnets with excellent magnetic properties.

When using the magnetic powder defined by the above formula,
By setting 0.60≦α≦0.85, a good maximum energy 'u! L((BH)max) can be obtained, and 0.10 or less in Fe can be obtained by combining N i , M n , C
o can be substituted with one or more types of N i
, improvement of coercive force (BHC, IHC) by Mn,
We can expect a one point increase due to Co.

In addition, by setting the range of O<β≦0.15, coercive force (BHC, IHC) and residual magnetic flux density (B
It is effective in improving the temperature coefficient of r), and by setting γ≦0.01, borides, carbides, and
Nitride, silicide.

By forming phosphides, etc., magnetic properties can be improved.

Therefore, in the present invention, more preferably, the rare earth-iron magnet powder produced by the ultra-quenching method is coupled with a silane-based or titanate-based coupling agent.

In the coupling treatment in this case, various silane coupling agents and titanate coupling agents are appropriately diluted with a solvent such as alcohol, toluene, or distilled water, and then dried.

Then, the magnet powder subjected to the coupling treatment after drying is mixed with a resin such as a thermosetting resin or a thermoplastic resin, and formed into a molded body of a predetermined shape by compression molding, injection molding, or the like.

Thereafter, the molded body is subjected to a curing treatment, if necessary.

Permanent magnets manufactured in this way have excellent corrosion resistance because the raw material magnet powder is coupled with a silane-based or titanate-based coupling agent. This makes it possible to prevent a decline in

(Example 1) A silane coupling agent (A-1100 manufactured by Nippon Unicar Co., Ltd.) was sprayed onto fine powder (particle size: 200 pm or less) of 3ONd-IB-Fe produced by an ultra-quenching method. Coupling treatment was carried out while adding. At this time, the amount of silane coupling agent added was 50 parts by weight of silane coupling agent, 135 parts by weight of ethyl alcohol,
Distilled water: A mixed solution of 15 parts by weight was adjusted so that the amount of the silane coupling agent was 2% by weight based on the fine magnet powder.

Next, the magnet powder coupled with the above silane coupling agent was dried by heating at 100'O for 3 hours, and then 2% by weight of epoxy resin was added and mixed.
It was compression molded into a cylindrical body with a diameter of 11 mm and a height of 10 mm at a pressure of cm, and the resulting molded body was subjected to a curing treatment by heating at 150° C. for 1 hour.

On the other hand, for comparison, a molded body was obtained in the same process as above using the same magnet powder but without coupling treatment.

Then, for the above two types of molded bodies, temperature: 50'
C. A Wenzhou test was carried out at 99% humidity for 2 hours and 96 hours, and the results are shown in Table 1.

(Example 2) Coupling was performed using a titanate coupling agent (T1-KRTTS manufactured by Ajinomoto Co., Inc.) to a fine powder of 3ONd-IB-Fe (particle size: 200 Bm or less) produced by an ultra-quenching method. processed. At this time, the magnet powder was immersed in a solution containing 100 parts by weight of a titanate coupling agent and 100 parts by weight of toluene to perform a coupling treatment.

Next, after performing a coupling treatment by immersing the magnet powder, the remaining solution was removed, and after drying by heating at 100°C for 3 hours, 2% by weight of epoxy resin was added and mixed. Diameter 11mm, height 1 with cm2 pressure
A cylindrical body having a length of 0.01 m was compression molded, and the resulting molded body was subjected to a curing treatment by heating at 150°C for 1 hour.

On the other hand, for comparison, a molded body was obtained in the same process as above using the same magnet powder without performing the coupling treatment.

Then, a 96-hour salt water spray test was conducted on the two types of molded bodies, and the results are shown in Table 2.

[Effects of the Invention] As explained above, according to the method for producing a permanent magnet according to the present invention, rare earth-iron based magnet powder is mixed with silane-based,
Coupling treatment with titanate coupling agent,
Next, it was mixed with resin and then molded, so
It has good magnetic properties and excellent corrosion resistance.
A very excellent effect is brought about in that permanent magnets can be manufactured by preventing deterioration of magnetic properties due to the occurrence of rust as much as possible.

Claims (1)

[Scope of Claims] (1) A method for producing a permanent magnet, characterized in that rare earth-iron magnet powder is subjected to a coupling treatment with a silane-based or titanate-based coupling agent, and then mixed with a resin and then molded. . (2) Rare earth-iron magnet powder is R_1_-_α_-_β_-_γFe_αX_βM_γ
, R is one or more rare earth elements, F
e is iron, X is one or more of B, C, N, Si, P, M is Ti, Zr, Hf, V, Nb, Ta, Cr, M
o, W, Al, and Zn, and is characterized by: 0.60≦α≦0.85, 0<β≦0.15, 0≦γ≦0.01. A method for manufacturing a permanent magnet according to claim (1). (3) The method for producing a permanent magnet according to claim (2), wherein 0.10 or less of Fe is replaced with one or more of Ni, Mn, and Co. (4) A method for manufacturing a permanent magnet according to any one of claims (1) to (3), characterized in that a curing treatment is performed after molding.