JPS60221551A - Permanent magnet alloy - Google Patents

Abstract

PURPOSE:To obtain a permanent magnet having superior magnetic characteristics by using a rare earth metal and an Fe-Co-B-P intermetallic compound as starting materials. CONSTITUTION:An intermetallic compound having a composition represented by a formula R(Fe1-X-Y-ZCoXBYPZ)A is refined. In the formula, R is one or more kinds of rare earth elements, 0<=X<=0.5, 0.02<=Y<=0.3, 0.0001<=Z<=0.03, and 4<= A<= 7.5. An ingot of the intermetallic compound is cooled and crushed, and the resulting powder is molded in a magnetic field and sintered at 1,100 deg.C for 2hr in an atmosphere of gaseous Ar. The sintered body is aged at 500 deg.C for 1hr and at 600 deg.C for 1hr to manufacture a permanent magnet having superior magnetic characteristics.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an intermetallic compound permanent magnet material O'1 consisting of a rare earth metal (hereinafter abbreviated as R) and Fe.

As is well known, R-Fe alloys, such as R2
Fe is a permanent magnet material that has a higher saturation magnetic flux than the R-GO base metal, does not contain expensive CO, and has a high permanent magnet yield. However, the required r l-1c as a permanent magnet material could not be obtained, and the device remained in use for a long time. In recent years, with the progress of liquid quenching technology, this method has been successfully applied to R-Fe alloys to obtain high coercive force. (For example, J, J,
Croat.

Journal of Applied Physics
s 52(3) March 1981, 2509”IV
la(]netiCPr0pretieSof mel
t-sun Pr-Fe allOys”)
Zarani, N. C., Koon et al. added a small amount of B to R-F.
High coercive force is achieved by super-quenching the e-8 alloy and aging crystallizing it at 600 = 800°C (N,
C0Koon et al Appl, PhysLet
ter 39(10)15(1981) 840”Ma
gneticPropret:es of A mo
rphous and Crystal l 1zed
(F eO,82Bo4B)O,Q T bo,o5
L "o, o5" JP-A-58-123853). However, the above manufacturing method requires a mixed state of crystalline and amorphous materials, and the form of the obtained material is generally limited to powder or ribbon. Therefore, the permanent magnet t
When using it as J'All, it is necessary to bulk it by compression molding or the like. Further, the powder obtained by ultra-quenching is isotropic and has a poor square shape, making it difficult to magnetize and causing many problems in practical use.

On the other hand, Sayo et al. used crystalline Nd-Fe-B to obtain high properties by forming it in a magnetic field and sintering it to make it anisotropic (29th 3M Conf, 1983 booklet).
P 11 (1, 5essionE B, E B-1”
New Materialfar Permanent
Magnets on a base afNd a
nd Fe”), the obtained magnetic properties are 35-4
0MGOe, the highest among rare earth magnets. However, the published material had the drawbacks of a low Curie point and poor thermal stability, which were major obstacles to its practical application.

The present invention has been made to improve the thermal stability of these R-Fe and -B alloys, and eliminates the above-mentioned drawbacks by improving I l-I C.

As a result of extensive study, the inventors found that the addition of P
It has been found that there is an effect of improving C.

The alloy of the present invention is R(Fe+-x-y-x Cox By
p,) A (where R: one type or a combination of two or more rare earth elements, 0≦X≦0.5. 0.02≦y≦0.3.
0.0001≦7≦0.03, 4≦△≦7.5). In the present invention, C
If the o-substitution ff1X exceeds 0.5, the 4πir decreases significantly, making it undesirable as a permanent magnet material. B@If y is less than 0.02, the Curie point will not increase and it will be high ■H
I can't get c either. On the other hand, when y exceeds 0.3, 4πIr decreases by one Curie point, and a phase with unfavorable magnetic properties appears. If the amount of additives 2 that improve coercive force is less than 0.0001, no improvement in IHC can be expected; on the other hand, 4πIr (
Br) and squareness are reduced, making it undesirable as a permanent magnet material. △ or 4 Unvortexed lifting platform, 4πl" has decreased, 7.
When the value exceeds 5, a phase rich in Fe and Cc appears, and I l-I
C decreases.

The permanent magnet according to the present invention is generally manufactured by IJA through the steps of melting into an ingot, crushing, forming in a magnetic field, sintering, and heat treatment. The melting is carried out in a conventional manner in Ar or vacuum. It is also possible to use ferroboron for B. In high-frequency melting, P is added after FC, C:O, and B are melted, and rare earth elements are added last. Grinding can be divided into coarse grinding and fine grinding, and coarse grinding is performed using stamp mills, show crushers, brown mills, and disc mills.
For fine grinding, there are four rows of jet mills, vibration mills, ball mills, etc. Both are carried out in a non-oxidizing atmosphere to prevent oxidation, and organic solvents and inert gases are used. The grinding particle size is 3-5 μm (r, S, S, S.

) is desirable. (Molding in a magnetic field improves the degree of orientation and anisotropic IL
Generally, either vertical magnetic field shaping (the direction of pressure and the direction of magnetic field application are parallel) or transverse magnetic field shaping (the direction of pressure and the direction of magnetic field application are perpendicular) are used. Horizontal magnetic field forming has better KlvA
The field forming main forming orientation degree is excellent. '13' A knot is Ar
, 1-IC or the like or in vacuum.

Furthermore, sintering in H2 gas is also possible. Rapid cooling is preferable for cooling after sintering, but if heat treatment is performed after sintering, cooling in a furnace may be used. The heat treatment varies depending on the type and composition of the rare earth element used, but is performed at a temperature of 400 to 1000°C.

The addition mz of the additive P in the present invention may be changed as appropriate within the range of 0.0001-0.03 depending on the type of application field and process. The same applies to the combination with the amount of CO substitution.

The present invention will be explained below with reference to Examples.

Example 1 N d (F e, 9-, B, 4 P 1 >5.
An alloy consisting of , was prepared by arc melting. The obtained ingot was coarsely ground in a stamp mill and a disc mill, and
After adjusting to less than mesh size, it was finely pulverized in a diene mill.

t5) The crushing medium is N2 scum, and the crushed grain stone is 3.3μ1
it(F.

S, S, S,). 15 ko of the obtained finely pulverized powder
Transverse magnetic field shaping was carried out in a magnetic field of e. Molding pressure is 2jOl'1
/'Cm2. The molded body was heated at 1100°C in an Ar atmosphere.
×21゛Sintered. After sintering, 500℃×1111・+6
The magnetic properties obtained are shown in Table 1. In Table 1, the addition of P shows an improvement in J and iHc.However, adding a large amount of Caused deterioration of 1c.

In addition, the obtained sample was added to a cylinder with L/D = 0.7,
The demagnetization rate (%1) was heated at 120°C
ass) was measured. Table 2 shows the results.

Table 2 shows that the addition of P improves the hardness Hc and, as a result, reduces the demagnetization rate.

Implementation 1 column 2 P r (F e, 1.q Bo, (P, ., ol) 5
An alloy having the following composition was melted, crushed, and sintered in the same manner as in Example 1. After sintering, it was rapidly cooled in an Ar gas flow. The obtained magnetic properties were as follows.

Br-12300G aHc~102000e Engineering Hc ~14500Q2 (B H) max ~34,7M G Oe Table 3 shows the results when the obtained samples were heat treated.

Table 3 shows that by adding aging, I@c exceeds 17 kOe. Furthermore, it was confirmed that the alloy of the present invention has superior thermal stability compared to conventional alloys.

Example 3 N d (F eo, q COo, +, -B., 1P
0, ooj) 51 was melted, crushed, and sintered in the same manner as in Example 1.

After sintering, aging was performed at 600°C xll+r. The determined magnetic properties were as follows.

Br-12000G BHc ~ 980008 I Hc ~ 1400000 (3 days) n1aX ~ 34.3M G Oe Furthermore, while the thermal stability was measured in the same manner as in Example 1, the inventive alloy's 1. Exhibited impressive characteristics.

Claims (1)

[Claims] R (Fe1-%-γ-, Cox B, P-i R8 (where R: one or a combination of two or more rare earth elements, 0≦
X≦0.5. 0.02≦y≦0.3. 0.0001
7.03.4≦A≦7.5).