JPS61106735A - Manufacture of permanent magnet alloy - Google Patents

Abstract

PURPOSE:To manufacture at a low cost a permanent magnet alloy which is excellent in its magnetic characteristic by mixing a powdery rare earth oxide, a granular reducing agent, and an Fe metallic powder, etc., and executing successively their heating, reducing diffusion and cooling under a specified condition. CONSTITUTION:A powdery rare earth oxide centering around Sm, Ce and Pr, granular reducing agent Ca, and a metallic powder of Fe, Co, Cu and M (one kind or two kinds or more of Si, Ti, Ni, Cr, Zr and Hf) or its oxide powder are mixed. This mixture powder is treated in an inert gas (Ar gas) atmosphere of a normal pressure or above at an ordinary temperature through 1,000 deg.C. Also, a temperature is raised and its reducing diffusion is executed in a reducing gas (H2 gas) of a normal pressure or above within a temperature range of 1,000-1,300 deg.C. Subsequently, its cooling is executed in an inert gas (Ar gas) atmosphere of a normal pressure or above at <=1,000 deg.C. In this way, a permanent magnet alloy shown by R(Co1-X-Y-ZFeXCuYMZ)A (R denotes a rare earth metal, 0.10<=X<=0.35, 0.02<=Y<=0.10, and 0.005<=Z<=0.10) is obtained.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to Cu-substituted rare earth intermetallic compounds, so-called R*C
The present invention relates to a method for manufacturing an O+v permanent magnet alloy.

[Conventional technology]

Rare earth cobalt magnets are roughly divided into RCow and Cu.
There are two types of substitution type R*CO+v type permanent magnets, and RCo5 type permanent magnets (see, for example, Japanese Patent Application Laid-open Nos. 46-65056504 and 6505) are known as the first magnets to be put into practical use. Afterwards, high performance was investigated in the RtCO+i system, and part of the Co was replaced with Fe, Cu and M (81,
T.I., Zr., V.

It is known that substitution with Nb, Cr, Mo, Hf, Ni, etc.) is an essential condition. (
For example, JP-A-53-106624, JP-A-56-11
No. 2455) As a manufacturing method of this more RmCO+y-based multi-component permanent magnet, rare earth metals, Co, Fe
The most common method is to use high-purity alloy constituent metals such as Cu and M metals as starting materials and melt and cast them in a crucible under an inert atmosphere. However, since rare earth metals are generally expensive, the above melting method requires high raw material costs, which is a factor that increases manufacturing costs.

Therefore, in order to improve the above-mentioned drawbacks of the dissolution method, reducing agents (CaL, Ca) are used using inexpensive rare earth oxides as raw materials.

Mg) using reduction diffusion reaction (hereinafter referred to as RD reaction)
proposed an alloying method.

For example, Japanese Patent Publication No. 49-7296 discloses a production method using CaL in an H or Ar atmosphere;
No. 3-16798 discloses a C&steam production process under reduced pressure. In addition,
No. 5 discloses a manufacturing method using Mg in an Ar atmosphere, and Japanese Patent Publication No. 55-27602 discloses a manufacturing method using Ca in an Ar atmosphere at 1000° C. or lower. However, the above-mentioned conventional methods have had problems such as inferior magnetic properties compared to the melting method.

An object of the present invention is to provide a manufacturing method capable of solving the above-mentioned problems of the prior art and producing a rare earth cobalt permanent magnet with excellent magnetic properties at low cost.

[Means for solving problems]

The present inventors referred to the above-mentioned known examples, and as a result of various studies, the reduction with Ca was carried out in an inert gas atmosphere such as Ar gas at a temperature of 1000° C. or less and a pressure above normal pressure, and then an inert gas atmosphere such as Ht gas, etc. Change to a reducing gas atmosphere of
By allowing the diffusion reaction to proceed in the temperature range of 1,000 to 1,600°C, and cooling the reaction below 1,000°C in an Ar gas atmosphere above normal pressure, the magnetic properties are significantly improved, and the magnetic properties are on the same level as the melting method. I found out what I could get.

Factors for improving the magnetic properties of the present invention include 1000 to 13
This is thought to be due to the progress of a reaction activated by the Ht gas atmosphere at 00°C. That is, the present invention provides s R (Cot -x-y-zFexcuyMz) people (
Here, R is one kind or a combination of two or more kinds of rare earth metals mainly Sm, Ce, and Pr) M is 81
．． Ti, Ni.

One or a combination of two or more of Cr, Zr, Hf,
1α10≦X≦0.35, α02≦Y≦0
．． 10, 0.005≦2≦0.10.

5≦A≦8.5) In a method for producing a permanent magnet alloy having a composition expressed as Then, the obtained mixture powder was treated from room temperature to 1000°C in an inert gas atmosphere such as Ar gas above normal pressure, and the temperature was further increased by 1°C to 1000°C to 13°C.
The temperature range of 00°C is reduced and diffused in a reducing gas atmosphere such as Ht gas at normal pressure or above, and the temperature range below 1000°C is cooled in an inert gas atmosphere such as Ar gas at normal pressure or above. It is. The reason why the atmospheric pressure is set above normal pressure is that if the atmospheric pressure is below normal pressure, costs such as equipment costs will be high. In detail, rare earth oxides (e.g. SmHO*
), granular Ca, and other metal powders (or oxides of some or all of them) are mixed, and then the temperature is raised to 1000° C. to perform a reduction reaction. During this temperature raising process, Ca (melting point around 800°C) in a liquid phase becomes S ms O
Reduce s (Sm*Os + 3Ca-+28m +3C
aO), the atmosphere may be Ar gas. In addition, a part of the multimetal oxide is also reduced by Ca. Next, 1000℃
When maintained at a temperature above, the reduced Sm becomes Fe,
It interdiffuses with Co, Cu, etc. and alloying progresses.

In this case, if the reaction is carried out in an H gas atmosphere, all the metal oxides will be reduced and the surface of each reduced alloy element including Sm will be activated by the L gas, so the diffusion reaction will occur quickly. It progresses and excellent magnetic properties can be obtained by holding for a short time of 1 to 3 hours. The holding temperature may be 1000°C or higher, but since the melting point of Sm is 1052°C, if the temperature is sufficiently higher than the melting point of Sm (1100°C), Sm will enter a liquid phase and form a liquid on other metal surfaces. A sufficient reaction can be carried out by wetting the material. However, even if the holding temperature is too high, it hardly contributes to the progress of the reaction, so a holding temperature of 1300° C. or lower is sufficient.

After the reaction is completed, cooling may be performed again in an Ar gas atmosphere.

Examples of the present invention will be described below.

Comparative Example 1 Metals Sm, Co, Fe, Cu and sponge Zr were melted in Ar using vacuum melting Rp,
The obtained ingot was coarsely pulverized with a known pulverizer (show crusher), and further finely pulverized with a jet mill to an average particle size of 3.4 μm (F, S, S, S). The obtained finely pulverized powder was designated as Sample/161, and Table 1 shows its analytical values.

Next, the finely pulverized powder was mixed with a magnetic field strength of 7KOe and a molding pressure of 4@A-d.
The molded product was press-formed under the conditions of H! Sintering was performed at 11,811° C. for 1 hour in gas. After sintering, it was held at 1160°C for 2 hours in Ar, then rapidly cooled to room temperature, and then heated again at 8
After holding at 00°C for 6 hours, the sample was gradually cooled to room temperature at a cooling rate of 1°C, and the magnetic properties were measured. The magnetic properties are shown in Table 2.

Comparative Example 2 SmtO, powder 2650? , Co powder 4040f,
Fe powder 1110f.

Cu powder 700r, zrα powder 19 (1, Ca grain 133
After mixing 0 P in a V-type mixer for 50 minutes, set it in a reaction vessel, raise the temperature to 1000 °C for 4 hours in an Ar gas atmosphere above normal pressure, and continue to heat it in an Ar gas atmosphere. 11
The RD reaction was allowed to proceed at 90° C. for 2 hours, and after the reaction was completed, it was cooled to room temperature. The obtained reaction cake was washed repeatedly by pouring it into water, and was further pickled, washed with water, dehydrated and dried to obtain magnetic powder. The obtained magnetic powder was finely pulverized with a jet mill (average particle size: 3.4μF7), molded, sintered, and heat treated under the same conditions as in Example 1, and subjected to measurement of magnetic properties. The composition and magnetic properties after pulverization are shown in Tables 1 and 2 as sample/I62.

Comparative Example 3 Reduction-diffusion reaction conditions 1190°CX2h to 1000°C
A magnet alloy was obtained under all the same conditions as in Comparative Example 2 except that the material was changed to X2h. The sample in this case was designated as Flat 5.

Example 1 The raw materials were blended in the same manner as in Comparative Example 2, and the mixture was heated to A above normal pressure.
The temperature was raised to 1000°C in 4 hours in an r gas atmosphere, and then the Ar gas atmosphere was changed to an H1 gas atmosphere above normal pressure, and the RD reaction was allowed to proceed under the conditions of 1190°C x 2 hours, and after the reaction was completed, the temperature was raised to 1000°C. The following was cooled in an Ar gas atmosphere at normal pressure or higher. The obtained reaction cake was treated under the same conditions as in Comparative Example 2 to obtain magnetic powder.

Furthermore, the obtained magnetic powder was treated under 0 conditions as in Comparative Example 2.
1. Molding, sintering, and heat treatment were performed, and the magnetic properties were measured. The composition and heat treatment characteristics of this example after pulverization are shown in Tables 1 and 2 as sample A4.

Comparative Example 4 Metals Sm, Co, Co, Fe, Cu and sponge Zr were melted in Ar using a vacuum melting furnace, and the obtained ingot was coarsely crushed using a known crusher (show crusher). The mixture was further pulverized using a jet mill to an average particle size of &7 μm (F, S, S, S). The obtained finely pulverized powder was designated as sample/I65, and its analytical values are shown in Table 3. Next, the obtained finely pulverized powder was subjected to a magnetic field strength of 7 KOe.

Press molding was carried out under the conditions of a molding pressure of 4 mm, and the molded product was
Sintering was performed at 1165° C. xih in a gas atmosphere.

After sintering, it was held at 1140°CX 2Hr in Ar gas, then rapidly cooled to room temperature, and again held at 770°Cxsh, slowly cooled to room temperature at a cooling rate of °C/min, and used for measuring magnetic properties. provided. The magnetic properties are shown in Table 4 (sample/l65).

Example 2 Sm snow 0 own powder 1270 f, Cede powder 155 (I
F, Co powder 390 (1.

Fe powder 1080P, Cu powder 6801, ZrO*
After mixing 180F powder and 154L of Ca grains in a type mixer for 30 minutes, set it in a reaction container and heat it with Ar at above normal pressure.
The temperature was raised to 1000℃ in a gas atmosphere for 4 hours, and then A
Change the r gas atmosphere to a Ha gas atmosphere above normal pressure, and
The RD reaction was allowed to proceed at 170° C. for 2 hours, and after the reaction was completed, it was cooled to 1000° C. or lower in an Ar gas atmosphere at normal pressure or higher. The resulting reaction cake was poured into water and washed repeatedly, followed by pickling, water washing, and dehydration drying to obtain magnetic powder. The obtained magnetic powder was finely pulverized with a jet mill (average particle size 5.7ttm SF, S, S, S), molded, sintered, and heat treated under the same conditions as in Comparative Example 4, and used for measuring magnetic properties. provided. The composition of this example after pulverization and the magnetic properties after heat treatment are shown in Tables 3 and 4 for sample 466.

As seen in /164 in Table 2 and 6 in Table 4, the magnetic properties of the magnet alloy obtained by the present invention are as follows: /%2. It can be seen that it is superior to /165 and is also at the same level as /I61 and Fu5 in the dissolution method.

Table 1 Analysis values (wt) Table 2 Magnetic properties Table 3 Analysis values (wt) Table 4 Magnetic properties Examples 6 to 5 The following is Example 1 with different holding conditions in H, gas atmosphere
A class 581 magnet alloy was obtained under the same conditions as above.

The compositions of these alloys are shown in Table 5ζ, and the magnetic properties are shown in Table 6.

Table 5 Analysis values (wt) Table 6 Magnetic properties Examples 6 to 8 Six types of magnet alloys were obtained under the same conditions as Example 2, except that the holding conditions in the L gas atmosphere were changed.

The compositions of these alloys are shown in Table 7, and the magnetic properties are shown in Table 8.

Table 7 Analysis Values (W1%-F18 Magnetic Properties and Effects of the Invention) As described above, the magnetic properties of the magnetic alloy obtained by the method of the present invention are different from those obtained by the melting method using expensive rare earth metals. At the same level, its industrial value is extremely large.

Procedural amendment (voluntary) 1□15?・12. ,．． 17.

Title of invention No. 228655 filed in 1980 Name of the person who amends the permanent magnet alloy σ pole manufacturing method
"L R (001-X-y-z aexouyMz) A
(Here, R is Sm.

QezPre is one kind or a combination of two or more kinds of rare earth metals, and M is Si, T1, N1.0rSZrH
One type or a combination of two or more types of f. α10≦X≦0
．． 35.0.02≦Y <A20.0.005≦Z W
, 10.5≦A≦&5) A method for producing a permanent magnet alloy having a composition represented by: a powdered rare earth oxide, a granular reducing agent Oa, and a metal powder or oxide powder of IFe, Co, Ou%M. The resulting mixture powder is heated from room temperature to 1000°C under an inert gas atmosphere above normal pressure FI! i Treated in air, further heated to 1000-1300°C0), reduced and diffused in a reducing gas atmosphere at normal pressure or higher,
(((
A method for producing a permanent magnet alloy, which includes cooling.

Ka2 The inert gas is Ar gas, and the reducing gas is H2.
A method for producing a permanent magnet alloy according to claim 1, wherein the permanent magnet alloy is a gas. ” 2. On page 4, line 18 of the same book, the statement “α02≦Y residence 10” is corrected to y 7coz≦Y $20J.

& On page 7, line 3 of the same book, “θ/♂” means t “t/α.”
1”, corrected.

4 Replace rLaaJ in Table 2 on page 11 of the same iF with 1
``Corrected as Engineering HoJ.

5. Replace “IHo” with “1” in Table 4 on page 11.
"I corrected myself."

已 rgHoJ and a certain request in Table 6 on page 12 of IIF.
1 phrase,” he corrected.

7. The term rIHoJ in Table 8 on page 13 of the same book has been corrected to read "construction period."

that's all 1′

Claims (1)

[Claims] 1, R(Co_1_-_X_-_Y_-_ZFe_XC
u_YM_Z)_A (here, R is one kind or a combination of two or more rare earth metals mainly Sm, Ce, and Pr, and M is one kind or a combination of two or more kinds of rare earth metals, mainly Sm, Ce, and Pr. Combination of two or more types. 0.10≦X≦0.35, 0.02≦Y≦0.10, 0
．． 005≦Z≦0.10, 5≦A≦8.5) In a method for producing a permanent magnet alloy having a composition represented by: powdery rare earth oxide, granular reducing agent Ca, Fe, Co, Cu,
M metal powder or its oxide powder is mixed, and the resulting mixture powder is treated from room temperature to 1000°C in an inert gas atmosphere above normal pressure, and then further heated to a temperature range of 1000 to 1300°C. A method for producing a permanent magnet alloy, which comprises reducing and diffusing in a reducing gas atmosphere at atmospheric pressure or higher, and cooling to 1000° C. or lower in an inert gas atmosphere at atmospheric pressure or higher. 2. The inert gas is Ar gas, and the reducing gas is H_
2. The method for producing a permanent magnet alloy according to claim 1, wherein the method uses two gases.