JPH02501101A - Method for manufacturing rare earth metal-transition metal-boron anisotropic sintered magnet - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] Rare earth-iron-boron anisotropic sintered magnet from ultra-quenched rare earth-iron-boron alloy ribbon flakes Method of manufacturing [Industrial application field] The present invention is a rare earth metal-transition metal-boron (R-T-B) with a high energy product. Regarding permanent magnets, in particular, anisotropic permanent magnets can be obtained by sintering compacts of rapidly cooled RTB alloy powder. The present invention relates to a method of manufacturing a permanent magnet.

[Conventional technology] As an R-T-B permanent magnet alloy, N, C, oon and B, N, Das are (Fe 0.82 = 0.18 0.9 0.05' La0.05'''Crystalline and B') Tb Regarding magnetic properties of crystalline alloys and crystal alloys ^pp1. Phys, Lett, 39 (10 ) (1981), 840 (Reference 1). They are alloy crystals occurs at a relatively high temperature of 900°C, marking the beginning of a dramatic increase in the intrinsic coercivity. It says that.

They believe that this crystallized state alloy is potentially useful as a low-cobalt permanent magnet. I found that.

J, J. Croat, amorphous R-Fe-B ( Nd and/or Pr are especially used as R) alloy as described in JP-A-59-06473. No. 9 (Reference 2゜U.S. Patent Application No. 414,936 and No. 508,266) Corresponding) and Japanese Patent Application Laid-Open No. 60-009852 (Reference 3. This is a U.S. patent application No. 508266 and No. 544728). reference References 2 and 3 use other transition metals instead of Fe or as part of Fe. This is disclosed. These magnet characteristics are 20~400nII NdFe1 This is thought to be due to the microstructure in which 4B magnetic crystal grains are dispersed in the amorphous iron phase. was given. Further, in R. Magnetism and Magnetic Materials 54-57 (1) by Hishra. 986) 450 (Reference 4).

The rapidly solidified alloy ribbon is, for example, described in Egai's paper "Low-FieldHagn". etic Properties of Anorphous A11oys (Low-field magnetic properties of amorphous alloys)”, Journal of The An erican CeralcSociety, Vol, 60, Nd March-April, 1977゜1), 1), 128-133 (Reference 5 ), prepared by the single roll method disclosed in .

A similar one-roll method is disclosed as “melt spinning method” in References 2 and 3. It is. In other words, the molten R-T-B alloy passes through a small orifice at high speed. It is injected onto the outer circumferential surface of a rotating copper roll. The molten alloy is rapidly rolled It is cooled to form a rapidly solidified alloy ribbon. And at relatively fast cooling rates, amorphous Gold is produced and at relatively low rates the metal crystallizes.

According to references 2 and 3, the cooling rate of the alloy ribbon on the relatively low temperature roll surface The main limiting factor is thickness. If the quenched alloy ribbon is too thick, the cooling surface The part of the metal farthest from cools very slowly and crystallizes in a soft magnetic state. . If the alloy cools very quickly. If so, the alloy is in an amorphous state and a very dense state. With a microstructure between dense crystalline states, i.e. cooling away from the cooling surface of the ribbon Surfaces with relatively slow velocities are more likely to crystallize, but rapidly colliding with a cooling surface The other side, which is cooled to varies in the thickness direction of the rapidly solidified alloy ribbon.

References 2 and 3 state that when the grain size in the direction across the thickness is substantially uniform, They tend to exhibit better permanent magnetic properties than those with different crystal grain sizes in the thickness direction. It states that

To produce practical magnets, amorphous alloys are crushed and formed into bonded magnets. Ru. References on this include Minnesota st. Paul, 19 Presented by R, W, and Lee at the International Magnetics Conference held on April 29, 1985. BEETransactions of Hagnetics, HAG-2 2, 8 [15, “PROCESSIN” published on page 1958 of 1985. G 0FNEODYHIUH-IRON-BORON MELT-8PUN R IBBONS To FULLYDENSE HAGNETS (Neodymium-Iron - Processing of boron melt-spun ribbon into high-density magnet)” (Reference 6) .

[Problem to be solved by the invention] Generally, amorphous alloys provide only isotropic magnets due to their crystallographic isotropy.

This means that high performance anisotropic magnets cannot be obtained from amorphous alloys.

However, reference 6 also describes the high density hot pretreatment of ground amorphous alloys. It is said that the magnetic orientation was greatly improved by upsetting the sample. It discloses that. However, this technology still has a sufficiently high energy product. For example, a hot-pressed magnet cannot give an anisotropic permanent magnet. 7, 9 k Gaussian residual magnetic flux density with an inherent coercive force of 16 kOe IHC and has an energy product (B H) max of 138 GOe.

JP-A No. 60-089546 (reference document 7) discloses a rapidly cooled R- A Fe-B permanent magnet alloy is disclosed. This alloy is mainly smaller than 5μm of tetragonal crystals. It contains a very dense composite structure, and -100 tile mesh (30 It is ground into a powder with a particle size of less than 0 μm, and is used as a bonded magnet. reference Reference 7 suggests the possibility of applying pulverized powder to sintered magnets, and the alloy table Although it is stated that C-axis anisotropy was confirmed by X-ray diffraction microscopy on the surface, The sintered magnet does not disclose, in fact, its ground powder is magnetically aligned Therefore, a sintered magnet with high magnetic anisotropy could not be obtained.

Sayo et al. reported in Japanese Patent Application Laid-Open No. 59-046008 (Reference 8) that R (especially Nd) Anisotropic R manufactured from an alloy ingot consisting of Fe and B by a normal powder metallurgy method -We proposed a Fe-B sintered magnet. This sintered magnet is more permanent than known Sm-Co magnets. As a magnet, it showed superior magnetic properties.

However, R-Fe-B alloy is easily oxidized during the magnet manufacturing process. The R-Fe-B alloy ingot has a magnetic crystalline phase of the intermetallic compound R2Fe14B. and an R-rich solid solution phase, and this solid solution phase consists of a non-R-rich solid solution phase. This is because it is always active to oxygen. Furthermore, this solid solution phase is ground into uniform particles. Corrosion resistant anisotropic sintered magnet with high energy product, therefore difficult to is difficult to manufacture.

In the prior art, the quenched R-T-B alloy ribbon is made into a powder with a small particle size distribution. Known to be easily crushed and have superior corrosion resistance compared to alloy ingots It is.

Therefore, the object of the present invention is to provide a method for producing anisotropic sintered magnets from rapidly solidified alloy ribbons. Our goal is to provide the following.

Another object of the present invention is, for example, to provide excellent (BH)nax of 138 GOe or more. An object of the present invention is to provide an anisotropic sintered magnet having excellent magnetic properties.

Yet another object of the present invention is to provide a rapid cooling method in which each particle has a highly uniform crystal orientation. The object of the present invention is to provide a method for obtaining gold powder.

[Means to solve the problem] The present invention provides a rare earth-transition metal-boron (R-T-B) sintered magnet with R2T14B Prepare an alloy powder containing crystal grains, insert this powder into a magnetic field, and It relates to a method of manufacturing by forming into a shape and sintering at a sintering temperature. be.

According to the present invention, the R-T-8 alloy powder prepares the R-T-B alloy in the molten state. process, rapidly cooling from a molten state to have crystal grains of a predetermined particle size and a predetermined A process of forming a thick quenched alloy ribbon and/or scales, and a step of turning the quenched alloy ribbon and/or scales into / or by a process of crushing the scales into a powder with an average particle size smaller than the above thickness. It is a rapidly solidified alloy powder produced by and thereby can be magnetically aligned in a magnetic field.

Each thin strip and/or scale is preferably 20 to 500 μm (more preferably ( 50-500 μm)) and the crystal grains are less than 10 μm (preferably It has an average particle diameter of 1 to 10 μm). The average particle size of the crushed powder is 0.3 to 15 μm (preferably 1.5 to 3 μm).

Sintering is preferably performed so that the crystal grains grow to a grain size of 7 to 30 μm. Delicious.

RT-8 alloy powder consists of R28, O ~ 65.0% balance T and B by weight Desirably, the transition metal component molecules in the R-T-B alloy are FeCox (x is 0.35 or more 1-x (lower).

The ribbons and/or scales are produced by the one-roll method, i.e. by rolling the molten R-T-B alloy into a small oval. It passes through the rear ice, is injected onto the outer peripheral surface of the roll rotating at a predetermined speed, and then The injected molten alloy is rapidly cooled to form a quenched alloy ribbon and/or a scaly quenched alloy. manufactured by the method.

According to another aspect of the invention, the molten alloy is sprayed onto a cooling plate or It is tomized and becomes a flat, scaly, rapidly solidified alloy.

In order to produce a powder consisting of particles with a small grain size distribution, the molten alloy is , both sides of the ribbon or scale are rapidly cooled with cooling start times staggered from each other. similar For this purpose, the quenched powder can be subjected to a heat treatment at a temperature of 650 to 950°C.

The present invention is based on the following new facts observed by the inventors. In other words, the original The authors believe that magnetic crystal grains of R2714B, such as Nd2Fe14B, are It has been found that the crystallization direction is in the C-plane direction of the crystal grains. Furthermore, growth When the crystal grains have a particle size of 5 μm or less, the C-plane in the quenched R-T-B alloy ribbon tends to be oriented along the surface of this alloy ribbon. Crystal particles are 5 μm When the crystal grows larger, it becomes needle-shaped, and the C-plane of the crystal is similar to that of the rapidly solidified alloy ribbon. Orient in the direction perpendicular to the surface.

These facts suggest that crystals should be uniformly distributed so that they generally have equal and relatively large particle sizes. When grown together, the rapidly solidified alloy ribbon was found to have high anisotropy. this The powder obtained by crushing the anisotropically rapidly solidified alloy ribbon is magnetically aligned in a magnetic field. Columns can be aligned and therefore shaped by a magnetic field.

It can be seen that anisotropic sintered magnets can be manufactured through a sintering process. Dew.

However, in the single roll method, crystal grains are formed in the thickness direction of the rapidly solidified alloy ribbon. They have different diameters. This is because the cooling rate differs between the outer peripheral surface of the cooling roll and the free surface of the ribbon. This is because that.

Therefore, the orientation of the crystal grains also differs in the thickness direction.

In this regard, the present inventor has proposed that if the orientations are separated from each other in the thickness direction of the ribbon, found that the orientations of adjacent grains are usually the same, even if the orientations of adjacent grains are different. Ta.

Briefly, the present invention provides rapidly solidified alloy ribbon with an average grain size of less than its thickness. and is ground into a powder consisting of particles containing crystals in which the C-plane extends in one direction. This is an attempt to create RT-8 alloy powder with higher anisotropy. . The milled powder can be magnetically aligned and has a high energy product It can be formed into the desired shape to be sintered into an anisotropic sintered magnet.

Examples of the invention will be described below.

K Minister ■ Yu An alloy ingot consisting of R35.0wt%, Bo, 9wt% and the balance substantially Fe. It was prepared by high frequency heating in an argon gas atmosphere. Used for R, Fe, B The raw material is Nd with a purity of 97% (and other materials mainly consisting of Ce and Pr components). ), ferroboron containing 20 wt% B, and electrolytic iron.

This ingot was again melted by high frequency heating in argon gas. The hot water was heated at a peripheral speed to produce a rapidly solidified alloy ribbon with a width of 5 mm and a thickness of approximately 100 μm. It is injected through a small orifice onto the outer surface of a copper roll rotating at a rate of 15 i/sec. Ta.

This rapidly solidified alloy ribbon consists of fine R2Fe with an average particle diameter of 0.1 μm dispersed in the ribbon. It had 14B crystal grains. The rapidly solidified alloy ribbon is milled into an average grain size of 0. 5μm, 1.5μm, 3.0ttm, 5.0μm, 10.0)tm, 15.0μ m, 30.0 μm.

Each of the seven powders was exposed to a pressure of 1 ton-f/cJ in a magnetic field of 20 kOe. It was also compression molded. The compact was placed in vacuum for 1 hour and then in argon gas. The mixture was sintered by being held at 1050° C. for 1 hour and then rapidly cooled to obtain a sintered body. This pottery The compact was aged in argon gas at a temperature of 630° C. for 1 hour. Then this The sintered body was magnetized in a magnetic field of about 30 kOe to become a magnet.

This magnet has a magnetic property, namely, a residual magnetic flux density Br.

Coercive force IHC and maximum energy product (BH) lax were measured. child The measured properties are shown in FIG. 1 in relation to the average particle size of the compacted powder.

From Figure 1, the average grain size is smaller than 15 μm, which is much smaller than the thickness of the rapidly solidified alloy ribbon. In small objects, (BH)llaX is found to be larger than 16HOe. Ru.

From Figure 1, (BH) nax increases at average particle sizes smaller than 10 μm. However, it can be seen that the average particle size increases further when the average particle size is 5 μm or less.

There is no lower limit to the average particle size of the molded powder, but particles of 0.3 μm or more are practically molded. .

Waribune ■yu An alloy ingot consisting of R40vt%, B1.0wt%, and the balance Fe was prepared in Example 1. Manufactured in the same manner as. The raw materials for R are 5wt% Ce and 15wt% Pr. It is made by adding 5 at % of Dy to didium, the balance of which is Nd.

Ferrophorone and electrolytic iron were used as raw materials for B and Fe.

From this alloy ingot, by the same method as in Example 1, at a circumferential speed of 3011/SeC. A rapidly solidified alloy ribbon was produced using rotating rolls. This rapidly solidified alloy ribbon is approximately 2 degrees long. It had a width and thickness of approximately 50 μm. F2[014 The B crystal particles had an average particle diameter of about 0.01 μm.

This rapidly solidified alloy ribbon is made up of two types of powder with average particle diameters of 2.0 μm and 20.0 μm. Shattered.

Two types of sintered magnets were manufactured from these two types of powder in the same manner as in Example 1, Magnetic properties were measured.

Table 1 shows the measured data.

Table 1 From Table 1, by using powder with an average particle size of 2.0 μm, other large average particle sizes can be obtained. It can be seen that higher magnetic properties can be obtained compared to the powder.

X1■yu 97% pure Nd (including Pr, Ce and other rare earth metals) and ferro Using boron, electrolytic iron, electrolytic cobalt, and 99.9% pure aluminum An ingot was prepared in the same manner as in Example 1.

This ingot has R40,0wt%, Bo,9wt%, and the balance F is 77CO2. Consists of 0A J3.

From this ingot, using a roll rotating at a circumferential speed of 5 n/sec, A flaky rapidly solidified alloy was obtained by the single roll method similar to Example 1. Each scaly quench The gold has a width of approximately 5 mm and a thickness of approximately 150 μm, and is dispersed in each flaky quenched alloy. The average particle diameter of the crystal particles obtained was about 0.5 μm.

These scale-like rapidly solidified alloys are made of two types with average grain sizes of 2.5 μm and 20.0 μm. Each was ground into powder. From these two types of powder, two types of magnets were prepared in the same manner as in Example 1. The magnetic properties of the magnet were measured. This is shown in Table 2.

Table 2 The magnetic properties of a magnet made from powder with an average particle size of 2.5 μm are as follows: O outperformed magnets made from x1 m powder.

Wari 1 Ward 1 Using the same raw materials as in Example 1, an R-T-B alloy ingot was prepared in the same manner as in Example 1. The raw materials prepared by the method are as follows: The ingot contains R32.0wt%, B1.0wt%, and the rest. % Fe.

From this alloy, by the same single roll method as in Example 1, each of about 2 to 50 n/sec Seven types of rapidly solidified alloy ribbons were produced with circumferential speeds within a range.

Seven types of rapidly solidified alloy ribbons each have a width within the range of 1 to 15 Ilffi and a width of 10 μm. , 20μm, 50μm, 100μm, 200μm, 500μm, 1000μm They had different thicknesses.

X-ray diffraction analysis of these rapidly solidified alloy ribbons revealed the following facts. 1) Each quenching The alloy ribbon contains R2Fe14B crystal grains dispersed therein.

2) For rapidly solidified alloy ribbons with a thickness of 200 μm or less, the crystal grains should be 3μ For rapidly solidified alloy ribbons with a particle size of less than m and a thickness of less than 500 μm, , a rapidly solidified alloy ribbon having a particle size of 10 μm or less and a thickness of 1000 μm or less It contained crystal grains with a grain size of 20 μm or more.

and 3) crystal grains that have grown to a diameter of 5 μm or less are parallel to the main plane of the ribbon. It has an oriented 0 plane. On the other hand, each crystal that grows larger than 5 μm has needle-like knots. It has a zero plane extending perpendicular to the main plane of the ribbon.

Each rapidly solidified alloy ribbon was pulverized into a powder with an average particle size of 3 μm, and this The powder was compressed into a compact at a pressure of 21 On-f/- in an orienting magnetic field of 20 koe. shaped. The compact was heated in vacuum for 1 hour at a temperature of 1080°C, followed by It was sintered by being held in a hot gas for 1 hour and then quenched. This sintered body is 6 It was aged at 30° C. for 2 hours in argon gas.

Thereafter, a magnetic field of 30 kOe was applied to this sintered body to form a magnet. of this magnet Characteristics were measured.

Figure 2 shows the thickness of the rapidly solidified alloy ribbon of powder used in the magnet and the measured magnetic properties. are doing.

From Figure 2 (BH) max and Br are However, IHC is a rapidly solidified alloy thin film with a thickness of 1000 μm. It can be seen that by using the belt, it is considerably reduced.

Margin below In J1 Retsu j.

R, 30.0 wt%, B 1.1 at% using similar raw materials.

An alloy ingot consisting of Fe remainder was prepared. Rapidly solidified alloy from this alloy ingot Rapidly solidified alloys in the form of thin strips or scales were produced by the single-roll method using similar steel rolls. . The width and thickness of these rapidly solidified thin alloy ribbons or flakes are approximately 1 to 10 mm. The circumferential speed is about 1 to 6011 SeC about 1 over the range of 10 to 500 μm. It was controlled by changing it in the range of ~60 Il/SeC.

Among the ribbons obtained, those with high circumferential speed become an amorphous alloy, and the remaining rapidly solidified alloy ribbon and the scale-like rapidly solidified alloy contains crystal grains having an average particle size of 0.01 to 10 μm, The crystal grains contained in each rapidly solidified alloy ribbon or scale-like rapidly solidified alloy have small grain sizes. Has cloth.

These quenched alloy ribbons or flake quenched alloys obtained at different circumferential speeds were separately It was ground into individual powders having an average particle size of approximately 2.5 μm.

Each powder was subjected to a pressure of 1 ton-f/cJ in an orienting magnetic field of 20 koe. The compact is then molded into a compact for 1 hour in a vacuum and then heated in a vacuum. It was sintered at 1070° C. for 1 hour in Rougon gas and then rapidly cooled. This sintered body Aging in argon gas for 2 hours at 650°C and applying a magnetic field of about 30 kOe. It was magnetized and made into a magnet.

The magnetic properties of this magnet were measured. Measurement of each magnet made from powder The data are shown in Figure 3 along with the average particle size in the powder.

As shown in Figure 3, by using a rapidly solidified alloy containing crystal grains, amorphous alloys can be used. It can be seen that the magnetic properties can be improved compared to the case where the However, if the crystal If the average particle size is larger than about 10 μm, compared to using an amorphous alloy, It is not possible to obtain high IHC by using

Husband and retainer superior An alloy ingot was manufactured using the same manufacturing method as in Example 2 and from the same raw materials. this The alloy ingot is R35.0wt%.

It consisted of Bo, 9wt%, and the balance Fe.

Two rapidly solidified alloy ribbons were prepared in the same manner as in Example 4 except for the peripheral speed.

These two rapidly solidified alloy ribbons were heated at 50 m/sec and 10 Il/sec, respectively. It was fabricated at a circumferential speed of c, with a width of about 2 m+ and about 10 mm, and a thickness of 15 μm and 100 μm. Each had one.

The crystal grains in the 15 μm thick rapidly solidified alloy ribbon have a grain size smaller than submicron. It was determined that the zero plane of some crystal grains was arranged parallel to the main plane of the rapidly solidified alloy ribbon. It was observed that there was a slight tendency toward

On the other hand, other ribbons with a thickness of 100 μm contain crystal grains of about 2 μm or less. Most of the zero planes of these particles are oriented in a direction parallel to the main plane of the rapidly solidified alloy ribbon. Ta.

Two magnets were manufactured from these two alloys in the same process as in Example 4, and the magnet characteristics were determined. The sex was measured. The measured data are shown in Table 3.

Table 3 A magnet made from a quenched alloy thin strip with a thickness of 100 μm is a quenched alloy thin strip with a thickness of 15 μm. It was found that the magnet exhibited better magnetic properties than other magnets made from strips.

K pull% J 7 An example of an alloy ingot consisting of R40.0wt%, B1.0wt%, and the balance Fe. It was prepared in the same manner as in 6. and a steep slope having a width of about 3 μm and a thickness of about 60 μm. A cold alloy ribbon was produced in the same manner as in Example 5 using a single roll method using a steel roll. . From this rapidly solidified alloy ribbon, the sintering temperature was 1050°C and the aging temperature was 650°C. A magnet was obtained in the same process as in Example 5 except that the temperature was used. The magnetic characteristics of this magnet It is shown in Table 4.

Table 4 U-jihadan An alloy ingot was prepared in a similar manner using the same raw materials as in Example 3. child The alloy ingot contains R40.0wt%, B1.11t%, and the balance Fe It consisted of 77CO20A Js. From this ingot, each approximately 15μ Two rapidly solidified alloy ribbons having a thickness of approximately 100 μm and a thickness of approximately 100 μm were prepared in the same manner as in Example 6. It was made by From these alloy ribbons, the sintering temperature was 1030℃ and the aging temperature was 650℃. Two magnets were manufactured using the same process as in Example 4, except for 1 hour. .

The magnetic properties of the individual magnets are shown in Table 5.

Table 5 In the same manner as in Example 8, R40.0 wt%, Bo, 9 wt%.

An alloy ingot consisting of the remainder Fe77CO20Aj3 was prepared. stop Then, from this alloy ingot, a width of about 3 m and a thickness of about 3 m was obtained using the same method as in Example 7. A 60 μm rapidly solidified alloy ribbon was produced. From this rapidly solidified alloy ribbon, the sintering temperature was 1050 A magnet was made in the same manner as in Example 5, except that a temperature of 630°C and an aging treatment temperature of 630°C were used. Manufactured.

Table 6 The obtained magnet had magnetic properties as shown in Table 6.

mday Nine alloy ingots were described in Example 1 using similar raw materials as in Example 1. manufactured by the method. These nine ingots have the same amount of B1.0wt%. Similarly, different amounts within the range of R27.5 to 65.0 wt%, and the balance from Fe. Ru. From these nine ingots, nine rapidly solidified alloys were produced at 10 to 20 n/se. Fabricated by single roll method using steel rolls rotating at different circumferential speeds in the range of c. did. These rapidly solidified alloys have thicknesses ranging from about 50 to 100 μm depending on peripheral speed. and has a width of approximately 5 fl, and each alloy has a fl of an average grain size of 0.2 μm. j, ll1ll crystal grains. In addition, some alloys are long thin strips that remain. The ribs are scaly.

These nine quenched alloys were ground into nine powders with an average particle size of approximately 2.5 μm. And so. From these nine powders, with a 2'Okoe orientation magnetic field, lton -f/ Nine molded bodies were obtained by compression of aa. 700 to 15 of these molded bodies Different sintering temperatures differing from each other by 50°C within the range of 00°C, the first hour was Sintered in air, then 1 hour in argon gas for a total of 2 hours, then quenched. did. The obtained sintered body was aged in argon gas for 2 hours. These sintered bodies was magnetized by applying a magnetic field of about 30 kOe to obtain nine magnets, and the magnetic field of these magnets was Stone properties were measured. The measured magnetic properties are shown in Figure 4 along with the R component in the rapidly solidified alloy. It is shown.

From Figure 4, by selecting the R component within the range of 28.0 to 65.0 wt%, It can be seen that (BH) l1aX of 158 GOe or more can be obtained.

X top plate 1 unit An example of an alloy ingot consisting of R40,0wt%, Bo,9wt%, and the balance iron. It was prepared by a method similar to that described in 2. From this alloy ingot, the circumferential speed Rapid cooling was performed in the same manner as in Example 10 using a steel roll rotating at 30 n/sec. An alloy ribbon was manufactured. This rapidly solidified alloy ribbon has a width of about 2 m and a thickness of about 50 μm. There is. The crystal grains in this rapidly solidified alloy ribbon have an average grain size of about 0.01 μm. It was confirmed that In addition to using this rapidly solidified alloy ribbon at a sintering temperature of 1020°C, A magnet was produced by processing in the same manner as in Example 10.

FIG. 7 shows the characteristics of this magnet.

X negative” [Ll In the same manner as in Example 3, R was 40.0 wt%, B was 1.0 wt%, and the balance was Fe. An alloy ingot was prepared. This ingot was heated at a circumferential speed of 5 II/Sec. Single roll using a steel roll similar to that shown in Example 10 except that A flaky rapidly solidified alloy having a width of about 5 mm and a thickness of about 150 μm was obtained by . Each scale-like rapidly solidified alloy was confirmed to contain crystal grains with an average grain size of 0.5 μm. It has been certified.

Example 10 except that the sintering temperature of these flaky rapidly solidified alloys was 1030°C. A magnet having the magnetic properties shown in Table 8 was obtained by processing in the same manner as described in .

Table 8 X-transfer PI 1dan Nd with a purity of 97%, DY and ferroboron with 5 at% added to Nd, and electrolytic iron. Using electrolytic cobalt as a raw material, R35,0 wt%, BO,'lt%, the balance is T=Fe1-, Cox(x=0.0.1.0.2.0.3. and 0.4. Prepare an alloy ingot of each of the following in the manner described in Example 1.

These ingots were melted and heated to a peripheral speed of 10 Il in the same manner as described in Example 1. It is injected onto the peripheral surface of a copper roll rotating at a speed of about 5fl in width and about 150μm in thickness. A rapidly solidified alloy was formed.

Each rapidly solidified alloy contained w1 fine crystal grains with an average grain size of 0.1 μm. child These rapidly solidified alloys were ground into powder with an average particle size of 2.5 μm, and heated at 20 kO. It was molded into a molded body under a molding pressure of 1 ton-f/cJ in a magnetic field of e.

These compacts were prepared as described in Example 5, except that a sintering temperature of 1060°C was used. A magnet was manufactured using the same method as the magnet, and the magnet properties measured in Figure 5 are shown in Figure 5. As shown in FIG. 5, a portion of Fe is replaced with Co up to 35 at%. Possibly (B H) It was found that nax was improved.

Cold plate 1A Two alloy ingots were prepared in a manner similar to that described in Example 13. . One ingot contained R40.0wt%, B1.0wt%, M part T (transition metal ), and the other ingot contained R40.0 wt%, B1. OI%.

The remainder T (transition metal) was composed of Fe9oCo1o.

From these ingots, quenched ingots each having a width of about 3 tm and a thickness of about 30 μm are produced. Gold was produced using a similar single roll process. Each quenched alloy has fine grains with an average grain size Confirmed to contain children. Same as Example 13 except that the sintering temperature was 1020°C. Two magnets were made from these rapidly solidified alloys using the same method and aged for 1 hour. It has been processed.

Table 9 shows the characteristics of these magnets.

Margin below Table 9 From Table 9, by containing Co as the transition metal T, Br and (BH) It is clear that l1ax is improved.

Tenjo” LL Dan Two alloy ingots were produced in a manner similar to that described in Example 3. One is , R40,0wt%, st,iwt%.

The remainder consisted of Fe97Ajs, and the other was R40.0wt%.

B was 1.1 wt%, and the remainder was Fe77CO20AJs.

From these alloy ingots, a width of about 5 r. Two rapidly solidified alloys with a thickness of approximately 100 μm were prepared.

Each rapidly solidified alloy contained crystal grains with an average grain size of 0.05 μm. these from the rapidly solidified alloy of The magnetic properties of these magnets are shown in Table 10.

Margin below Table 10 From Table 10, the addition of cobalt improves Br and (BH) 11ax. I understand that.

11 dishes 1 yen Example 1 An alloy ingot consisting of 32 wt% R, 1.1 μl% B, and the balance Fe It was made in the same way as. From this alloy ingot, the peripheral speed is 10 i/sea A rapidly solidified alloy ribbon was prepared using a similar single-roll method using a copper roll. This quenched alloy The ribbon has a width of about 5 to 10 mm, a thickness of about 50 to 1100 AL, and an average particle size of 0. ．． It contained crystal grains of 3 μm.

This rapidly solidified alloy ribbon was crushed into powder with an average particle size of 2.5 μm, and a powder with an average particle size of 20 kOe was Shape into a molded body under a pressure of 2 ton-f/cJ in an orienting magnetic field.

This molded body was heated at a temperature of 1000 to 1120"C in a vacuum for 1 hour, and then subjected to an The sample was sintered for 1 hour in a dark atmosphere. The sintered body has a saturated sintered density, and at the sintering temperature It contained crystal grains with a dependent average particle size of 5 to 30 μm.

This sintered body was aged at a temperature of 650'C for 2 hours in argon gas, and then , magnetized in a magnetic field of 30 kOe. The magnetic properties of this magnet were measured.

The measurement data is shown in Figure 6 along with the average particle diameter of the sintered body. High magnetic properties can be obtained when the average crystal grain size in the aggregate is 7-30 μm. I understand.

K1 plate 11 The alloy ingot produced in Example 11 was subjected to the same single roll method as in Example 16. A rapidly solidified alloy ribbon was prepared.

The circumferential speed was approximately 1511/sec, and the obtained rapidly solidified alloy ribbon had a width of approximately 5 mm and a thickness of approximately It had a diameter of 50 μm. The crystal grains in this rapidly solidified alloy ribbon have an average grain size of approximately 0.1 It was μm.

Two molded bodies were molded from the powder in the same manner as in Example 16, and heated to 980°C. and 1050°C, respectively, and then timed in the same manner as in Example 16. Effectively treated.

These sintered bodies have sufficient sintered density (true density) and have a sintering temperature of 980°C and 1 The grown crystals with average particle sizes of about 6 μm and about 15 μm, respectively, for 050°C. It had crystal particles.

After sintering and aging, it was magnetized in the same manner as in Example 16, and the magnetic properties were measured. . The measured data are shown in Table 11.

Table 11 X day By the method shown in Example 3, R was 35.0 wt%, B was 1.0 wt%, and the balance was F. An ingot consisting of e77B20AJ3 was produced. This ingot From the above, an alloy ribbon was prepared using a roll rotating at the same speed of 5 m/sec. . The width and thickness of this rapidly solidified alloy ribbon are approximately 10 μm and approximately 200 μm, respectively. The average particle size of the crystal grains in the cold alloy ribbon was about 0.5 μl.

The two molded bodies were formed in the same manner as in Example 17, and each Sintering was carried out at temperatures of 1000°C and 1080°C. These sintered bodies each have an average It had grown crystal grains with particle diameters of 6 μm and 15 μm. These sintered bodies , and was subjected to aging treatment and magnetized in the same manner as in Example 17. The magnetic properties are shown in Table 12. vinegar.

Table 12 Next, the crystal grains of the rapidly solidified alloy ribbon or scale-like rapidly solidified alloy produced by the single roll method are Three examples in which heat treatment was performed to improve the orientation will be described.

Margin below X dispatch, PI 3rd In the same manner as in Example 1, R was 33.0 wt%, B was 1.0 wt%, and the balance was Fe. An alloy ingot is prepared, and a copper roll rotating at a circumferential speed of Iom/SeC is prepared. A rapidly solidified alloy ribbon was produced by the single roll method used. Each quenched alloy ribbon has a width of It has 5 parts and a thickness of 50 μl. Each quenched alloy ribbon has a NdFe 14B crystals with a particle size of 1 μm or less with mainly oriented 0 planes It was confirmed that crystal particles were dispersed. In particular, the free surface away from the roll surface The surface has a large surface with high crystal orientation compared to the quenching surface that impinges on the roll surface. It has crystals with a particle size of .

These rapidly solidified alloy ribbons were heated at 600°C, 700°C, 800"C, 900°C, Each was heat treated at 0°C for 1 hour and ground into a powder with an average particle size of about 3 μm. .

These powders were heated to 2 tons of These molded bodies were molded under pressure into molded bodies for 1 hour in a vacuum at 1080°C. Subsequently, the mixture was sintered in an argon gas atmosphere for 1 hour, and then cooled to obtain a sintered body. 62 sintered bodies It was aged at 0° C. for 2 hours and magnetized by applying a magnetic field of about 30 kOe. Obtained magnet FIG. 7 shows the magnetic properties of the magnet along with the heat treatment temperature.

From Fig. 7, Br and (BH) nax are It can be seen that it is greatly improved.

shi-bottom margin Tokari” LLdan An ingot consisting of R35,0 wt%, BO,,9 wt%, and the balance Fe was prepared in Example Prepare in the same way as described in 2.

From this ingot, two liquid quenched alloy ribbons were prepared in the same manner as in Example 19. Prepared. These rapidly solidified alloy ribbons have grain sizes with crystal orientation parallel to the main surface of the ribbon. It contained crystal particles of 2 μm or less. One of these rapidly solidified alloy ribbons was heated to argon gas. Heat treatment was performed at 800° C. for 1 hour in a bath.

The heat-treated alloy ribbon and the non-heat-treated alloy ribbon were each crushed. After powdering, these powders were sintered at a temperature of 1050°C. A sintered magnet was manufactured in a manner similar to that described in Example 19. The magnet thus obtained The magnetic properties of the stones are shown in Table 13.

Table 13 Table 13 shows that this heat treatment improves the magnetic properties.

Tribe dish lyu A case consisting of R40.0wt%, B1.1wt%, and the remainder Fe77C02oAj3. Gold ingots were prepared in a manner similar to that described in Example 3. This ingo Two rapidly solidified alloy thin sheets were prepared from the sheet by a single roll method similar to that described in Example 19. I prepared the obi. These rapidly solidified alloy ribbons have grains oriented parallel to the main surface of the ribbon. It had Nd2(FeCOAj)14B crystal particles with a diameter of 3 μm or less.

One of these rapidly solidified alloy ribbons was heat treated at 800°C for 1 hour in argon gas. Ta. The heat-treated quenched alloy ribbon and the non-heat-treated quenched alloy ribbon, respectively. was crushed in the same manner as in Example 19, and a sintered magnet was obtained at a sintering temperature of 1050°C.

The magnetic properties of the thus obtained magnet are shown in Table 14. It can be seen that the magnetic properties are greatly improved.

Table 14 Next, an example of a rapidly solidified alloy in which a magnetic field is applied during rapid cooling will be described.

The use of such rapidly solidified alloy powders improves sintered magnets.

K1 Takumi Yu In the same manner as described in Example 1, R34.0wt%, B1.0wt%, and the remainder An alloy ingot made of Fe was produced. From this ingot, the peripheral speed is approximately 10 By the single roll method using a copper roll rotating at m/SeC, the width is about 5 mm and the thickness is about 5 mm. Two quenched alloy ribbons with μl were prepared.

One of these quenched alloy ribbons was subjected to a magnetic field during quenching. Figure 8 shows the magnetic field markings. This equipment shows the equipment used to prepare quenched alloy ribbons while It has a melting tube 21 made of, for example, quartz, which melts the gold ingot into a molten state. Ru. This melting tube 21 has a small orifice for injecting the molten alloy onto the roll 24. 22. The opposite sides of the roll 24 are made of non-magnetic steel and have a central axis. Two hollow disk-shaped gauges 25 and 2 with a shared rotation axis 26 and 26' 5' is located. These containers 25, 25' are made of rotors magnetized in the thickness direction. It has roll-shaped permanent magnets 27 and 27', and the same magnets are placed on the opposite surface of the roll 24, respectively. Polar planes are placed. Therefore, the magnetic flux from both magnets 27 and 27' is Flows in a radial direction around the circumferential surface.

In this embodiment, each magnet 27 and 27' has a diameter of 20, a thickness of 2.5QI, and a diameter of 1 A disk-shaped samarium cobalt magnet with a surface magnetic flux density of kGaUss used. An iron roll having a diameter of 21 (2) and a thickness of 2.0 cm is used as the cooling roll 24. and used it. The magnetic field at the outer peripheral surface was about 3 kOe.

The rotating shaft 26 and 26' together, the molten alloy '23 is passed through the orifice 22. The mixture was injected onto the peripheral surface of the roll 24 to produce a rapidly solidified alloy ribbon. Therefore, the rapidly solidified alloy ribbon is It was exposed to a radial magnetic field on the roll 24. Therefore, the magnetic field is was applied in the thickness direction during quenching.

On the other hand, using a device in which the magnets 27 and 27' of FIG. 8 are replaced with non-magnetic rolls, Other rapidly solidified alloy ribbons were prepared. Therefore, there is no magnetic field in this rapidly solidified alloy ribbon. Not applied. These rapidly solidified alloy ribbons can be determined by X-ray diffraction to a size of several microns or less. It was found to have crystal grains. Rapidly solidified alloy ribbon with magnetic field applied Compared to other quenched alloy ribbons that were not It has many crystal grains with oriented 0 faces.

These rapidly solidified alloy ribbons were each ground into powder having an average particle size of 2.5 μm. Each molded body was molded under a molding pressure of 1 ton・f/- in a magnetic field of 20 kOe. Molded.

These molded bodies were heated at a temperature of 1060°C in vacuum for 1 hour and in argon gas for 1 hour. After sintering for an hour, it was cooled. The obtained sintered body was heated at 650°C in argon gas for 1 hour. After aging treatment, it was magnetized by applying a magnetic field of 30 kOe. Magnetism of the obtained magnet The chemical properties are shown in Table 15.

Margin below Table 15 From Table 15, it can be seen that the magnetic properties are significantly improved by applying a magnetic field.

Next, rapidly solidified alloy ribbons and/or flaky rapidly solidified alloys are produced with uniform crystal orientation. An example in which the magnetic properties of a sintered magnet are improved by doing so will be explained.

FIG. 9 shows the rapidly solidified alloy ribbon and/or flake-like shape with improved uniform crystal orientation. Figure 2 shows an apparatus for preparing rapidly solidified alloys.

This device includes a melting tube 31 made of, for example, quartz and having a small orifice 32. have The alloy 33 is melted within this melting tube 31. The cooling roll 34 is an orifice. is located below the orifice 32, so that the molten alloy passes through the orifice 32. It is injected onto the circumferential surface of a roll 34 that rotates at a predetermined speed.

As shown in the enlarged cross-sectional view of FIG. 9(a), the circumferential surface of the roll 34 has a Many protrusions 35 are formed to define a ridge 36 between two protrusions 35.

In the following example, the protrusions 35 are arranged at 1 inch intervals and have a radial height of 0.5+m+. It is formed.

A circular cooling plate 27 having a rotating shaft 38 has its main surface facing the circumferential surface of the roll 34. It is placed on the side of the roll.

When the molten alloy is injected onto the circumferential surface of the roll 34, the protrusions 35 cause the cooling plate 37 to It is scattered on the main surface as atomized granules. Each granule collides with the main surface of the cooling plate. It is flattened and cooled to become a scaly rapidly solidified alloy.

K standing and lyu In the same manner as described in Example 1, R32.0wt%, B1.0wt%, the remainder An ingot made of Fe was prepared.

From this ingot, a rapidly solidified alloy ribbon was prepared using the same single roll method as in Example 1. . In this case, the circumferential speed of the roll is changed in the range of about 2 to 80 m/sec, and the circumferential speed of the roll is changed in the range of about 2 to 80 m/sec. 5-15 width and thickness 10, 20, 50. ioo, 200,500°1000μ Rapidly solidified alloy ribbons each having I were obtained.

On the other hand, from the same ingot, using the apparatus shown in Fig. 9, a scaly rapidly solidified alloy was made. By changing the prepared 0 lap speed over a range of approximately 2 to 100 m / 5 CIC. We prepared scale-like rapidly solidified alloys with multiple lofts. Therefore, the obtained scaly quenched alloy varies from 0.5 to 10 + m + width and about 7 to 1000 μm depending on different circumferential speeds. It had a thickness of

The grain size distribution and crystal grain orientation in these rapidly solidified alloy ribbons were as follows: It was observed that it was similar to that of cold alloy ribbon. Furthermore, the uniform crystal orientation Compared to the conventional method, scaly and steep particles with a thickness of 500 μm or less, especially 7-50 μm, are produced due to scattering. It was confirmed that cold alloys were improved.

These rapidly solidified alloy ribbons and multiple lots of flaky rapidly solidified alloys are crushed, Powders with an average particle size of 3 μl were heated to 20 kO with a pressure of 2 ton-f/-. It was molded into a molded body in an orientation magnetic field of e.

After sintering these compacts under the same conditions as in Example 4, they were sintered at a temperature of 650°C for 1 hour. Aged. After that, a magnetic field of 3 Q koe is applied to these sintered bodies to make them magnetic. It turned into stone.

The magnetic properties of the obtained magnet were evaluated using a rapidly solidified alloy ribbon produced by the single roll method and the scattering method. FIG. 10 shows the thickness of the flaky rapidly solidified alloy produced. Produced by scattering method The magnet using the flaky rapidly solidified alloy is manufactured by the single-roll method with a thickness of 500 μm or less. It can be seen that the magnetic properties are improved compared to the magnet made from the rapidly solidified alloy ribbon. . Furthermore, by using a scaly rapidly solidified alloy with a diameter of 7 μm or more, considerably high Br and (BH) [It can be seen that Iax is obtained.

K1 plate lyu From the ingot prepared in Example 6, 10 approximately circular scale-like rapidly solidified alloys were obtained as shown in FIG. Each flake-like quenched alloy was semi-polarized using the apparatus shown in . fi and contained crystal particles having a particle size of about 1 μl or less. This scaly Magnets were manufactured from the rapidly solidified alloy in a manner similar to that described in Example 6.

The magnetic properties of the obtained magnet were determined in Example 6 using a rapidly solidified alloy thin film having a thickness of 15 μm. It is listed in Table 16 along with the magnetic properties of the magnet made from the strip.

Table 16 It can be seen that the magnetic properties of this example are considerably improved compared to Example 6. .

1 shaku 1 yu 25 Using the ingots prepared in Example 8, each having a thickness of 15 μm, one A scale-like rapidly solidified alloy with a diameter of 10 pieces was prepared in the same manner as in Example 24. . A magnet was made from this flaky rapidly solidified alloy in a manner similar to that described in Example 8. Built.

The magnetic properties of the obtained magnet were compared with the test sample made from the 15 μm rapidly solidified alloy ribbon of Example 8. Table 17 shows the magnetic properties of the materials.

It can be seen that this example has clearly improved magnetic properties.

Margin below Table 17 Next, the rapidly solidified alloy is prepared by other methods to provide improved magnetic properties. Four examples using powder will be described.

The method will be explained with reference to FIG. The apparatus shown in FIG. It has a melting tube 41 and a spray nozzle 42 arranged below the melting tube 41. 0 alloy is melted in melt tube 41. Spray compressed argon gas Ar By applying a voltage to the nozzle 42, the molten alloy 43 passes through the spray nozzle 42. and is atomized to become atomized particles P. This method is similar to the spray method for producing amorphous alloys. The atomized particles are cooled to form circular balls or granules. In the illustrated device 2, a cooling plate 44 made of copper or the like is disposed below the nozzle 42. placed and rotated. The atomized particles P collide with the main surface of the cooling plate 44 and are deformed, After cooling, it becomes a small plate-like flake-like rapidly solidified alloy F.

K family plate l ball An alloy ingot consisting of 30.0 wt% R, 1.0 wt% B, and the balance Fe was produced. It was prepared using the same dissolution method and the same raw materials as in Example 1.

The alloy ingot was formed with a thickness of about 10 mm using a water-cooled mold. . From this ingot, prepare 10 granules or globules using a known spraying method. did. Each of the granules had a particle size of approximately 0.2 ra.

On the other hand, 10 pieces of flaky rapidly solidified alloy were prepared using the apparatus shown in FIG.

Each scale-like quenched alloy has a diameter of about 0.3 mm and a thickness of about 100 μl.

The microstructures of this alloy ingot, granular alloy, and scaly rapidly solidified alloy are shown in Figure 12(a). , FIG. 12(b), and FIG. 12(C), respectively.

As shown in Figure 12(a), the ingot is a large-sized Nd2Fe14B grown The main phase of crystal grains (for example, the white area indicated by A in the figure) and the Between the precipitating iron grain prephase (small white area, for example, indicated by B in the figure) and this main phase, It consists of a Nd-rich crystalline phase (for example, shown in black at C in the figure) dispersed in the Nd-rich crystal phase.

As shown in FIG. 12(J), the granules are Nd2Fe1 with a particle diameter of 5 μt. The main phase of the 4B crystal (for example, indicated by the white area at A in the figure) and the dispersion within this main phase. A small amount of iron phase (e.g., indicated by the small white area at ``B'' in the figure) and this It consists of Nd (for example, shown in black as C in the figure) dispersed between the main phases.

As shown in Figure 12(c), the scale-like rapidly solidified alloy consists of needle-like crystals of Nd2Fe14B. It consists of the main phase of the particles and the Nd-rich layer at the interface of the crystal particles. The 0 face of a crystal particle is Generally oriented in a direction perpendicular to the main surface of the scale-like rapidly solidified alloy.

This alloy ingot, 10 pieces of granules, and 10 pieces of scaly rapidly solidified alloy were each It was ground to form a powder having an average particle size of 3.0 μm.

Each powder was heated in an orienting magnetic field of 25 kOe under a pressure of 2 ton-f/-. These six molded bodies were compression molded at 1000°C and 1020°C. ℃, 1040℃, 1060℃, 1080℃, 1100℃ for the first hour and the next one. Each time was sintered in vacuum and then cooled down.

The six sintered bodies obtained were heated at 650°C for 5 hours by applying a magnetic field of about 30 kOe. It was magnetized. The magnetic properties of the obtained magnet were examined in the 13th study along with different alloy powder manufacturing methods. As shown in the figure.

As is clear from Fig. 13, the magnet made from granular powder is made from ingot powder. Although it has better magnetic properties than magnets made from scaly rapidly solidified alloy powder, Magnets made from powder have better magnetic properties than magnets made from other powders. You can see that it is true.

1 pile of fire An ingot consisting of R30.5wt%, B1.0wt%, and the balance Fe was prepared in Example It was prepared in the same manner as described in 1. From this ingot, particle size 50 μ■ 10 granules with a diameter of about 50 μm and a thickness of about 30 μI The alloy was produced by a known gas atomization method and a method using the apparatus shown in Figure 11. , each prepared. These granules and scale-like rapidly solidified alloys contain Ne2F of less than 3 μm. It has a y&1Ill structure consisting of e14B crystal grains and Nd-rich phase at the interface between the crystals. Was. Furthermore, X-ray diffraction revealed that the 0 face of the crystal grains of each scale-like rapidly solidified alloy was It was found that the flaky rapidly solidified alloy was oriented uniformly in the direction parallel to the main surface. .

These granules and scaly rapidly solidified alloys were each ground into powders with an average particle size of 4 μm. Each was formed into a molded body in a manner similar to that described in Example 26.

The obtained molded body was heated at 1080°C in vacuum for 1 hour, and then in argon gas. It was sintered for 1 hour and cooled. These sintered bodies were aged at 650℃ for 5 hours. Magnetize in a magnetic field of 25 kOe.

The magnetic characteristics of these magnets are 1. The magnets made from granular powder shown in Table 18 are , has excellent magnetic properties, but other magnets made from scale-like rapidly solidified alloys are better. But it's better than these.

Table 18 dog 1” (1dan) The ingot was processed in the manner described in Example 2 '4. Prepared. This ingot is composed of R31, 5wt%, Bo, 9wt%, and the balance Fe.

From this ingot, 10 tons of granules each having a diameter of approximately 0.1+m and A 10 ton scale-like rapidly solidified alloy having a diameter of 0.3 mm and a thickness of 50 μt was prepared as Example 27. It was produced in a similar manner. These granules and scales are each crushed to a uniform grain size. A powder having a diameter of 3.5 μm was used, and molded bodies were formed in the same manner as in Example 26. Shaped. These molded bodies were sintered at 1060°C and then cooled.

These compacts were aged at 650°C for 3 hours, and then aged in a 25 kOe magnetic field. It was magnetized with

Table 19 shows the magnetic properties of the obtained magnet.

Table 19 R32,0w1%, B1.1wt%, remainder F e 77CO20A J13 An ingot was prepared as described in Example 3.

10 tons of granules with a diameter of approximately 0.1 mm and a diameter of approximately 0.3 mm and a thickness of approximately 50 μm. 10 tons of flaky quenched alloy having l I prepared it.

From each of these granule and flake-like rapidly solidified alloys, similar to those described in Example 28 The magnetic properties of the obtained magnet are shown in Table 20.

Table 20 Next, prepare rapidly solidified alloy ribbons with crystals with improved uniform orientation and grain size. Therefore, there are two or three practical methods that can provide a sintered magnet with further improved magnetic properties. An example will be explained.

An apparatus for preparing such an improved rapidly solidified alloy ribbon is shown in FIG. It has a melting tube 51 made of quartz, for example, with a small orifice 52 on the bottom. The 0 alloy is melted in the melting tube 51 to a molten state shown at 53.

A cooling roll 54 is placed below the orifice 52, and the 0 alloy molten metal 53 is placed under the orifice 52. It passes through the orifice 52 and is injected onto the outer peripheral surface of the roll 54. Another roll 55 The outer circumferential surface 54 has an outer circumferential surface spaced apart from this outer circumferential surface by a small gap. is located close to. Rolls 54 and 55 are rotated at the same speed and in opposite directions. Rotate to .

The molten alloy is injected from the orifice 52 onto the outer circumferential surface of the roll 54, forming a rapidly solidified alloy ribbon. form. The free surface of this rapidly solidified alloy ribbon 56 then comes into contact with the circumferential surface of the roll 55. touch

Therefore, the free surface of the quenched alloy ribbon 56 is also quenched by the roll 55, but the free surface of the quenched alloy ribbon 56 is There will be a delay in cooling from the opposing surface that collides with.

In the prior art, the method using two rolls is difficult to form an amorphous alloy ribbon. This method is known as the "double roll method". In that method, Referring to FIG. It is injected into the cap. Therefore, the molten metal is rapidly cooled from both sides at the same time. related to this Therefore, the single roll method using a single roll disclosed in References 2 and 3゜5 is called “single roll method”. It is also called ``Le method''.

The apparatus shown in Figure 14 uses two rolls similar to the twin roll method. but , the molten alloy contacts the two rolls not simultaneously but at different times. therefore, The method using the apparatus shown in FIG. 14 is called the "modified twin roll method."

K1 plate yutan An example of an alloy ingot consisting of R32.0w1%, B1.0w1%, and the balance Fe It was prepared in the same manner as described in 1.

From this ingot, steel rolls 54 and 55 are rolled using the apparatus shown in FIG. A rapidly solidified alloy ribbon was produced while rotating at a circumferential speed of 1,000 m,'sec.

This rapidly solidified alloy ribbon is called ribbon A. The ribbon A has a width of about 10 mm and a thickness of about 100 μm. It has a certain quality.

For comparison, other thin films were tested using the same circumferential speed by the single-roll method and the twin-roll method. Bands B and C were produced, respectively.

X-ray diffraction reveals that these ribbons A, B and C contain Nd2F dispersed therein. It was confirmed that it contained e14B crystal particles. The ribbon A is cooled by the first roll 54. The surface has microcrystals with particle sizes from submicron order to 3 μl, It is mostly unoriented, while the surface is cooled by the other disk 55. The surface and the intermediate region within both surfaces have crystals with a grain size of 1 μm to 3 μm, which are almost It is almost uniformly oriented.

In rapidly solidified alloy ribbon B, the surface cooled by the rolls is from submicron order to up to 3 μl, show very fine crystal grains that are hardly oriented; On the other free surfaces and in the intermediate range between both surfaces, large, 1-5 μm, almost uniform It shows needle-like crystal grains oriented in

In ribbon C, the opposing surfaces have submicroscopic structures that are hardly uniformly oriented. It shows microcrystals with a grain size of 3 μt from the center, while the middle region on both sides is slightly uniformly distributed. It had oriented crystals.

Grind ribbons A, B and C into powders each having an average particle size of about 3 μm. , molded at a molding pressure of 2 ton・f/cd in an orientation magnetic field of 20 kOe, respectively. did.

The compacts were heated in vacuum at 1000°C for 1 hour, followed by 1 hour in argon gas. After sintering, it was cooled.

The obtained sintered body was magnetized by applying a magnetic field of about 30 kOe to form a magnet. . The magnetic properties of these magnets are shown in Table 21.

Table 21 From this table, the magnet made from ribbon B is compared with the magnet made from ribbon C. However, the magnet made from ribbon A has improved magnetic properties compared to the magnet made from ribbons B and C. It can be seen that this is superior to the manufactured magnet.

K1 呵 11 From the ingot prepared in Example 30, the deformed twin roll method and the twin roll method were used. Rapidly solidified alloy ribbons A and B were prepared. The moving speed of the roll surface is approximately 2 m/sea. Therefore each quenched alloy ribbon A and B has a width of about 10 mm and a width of about 500 mm/sea. It had a thickness of μl.

From these rapidly solidified alloy ribbons A and B, the sintering temperature was set at 1050°C, A magnet was produced in the same manner as in Example 30. The magnetic properties of the obtained magnet are Shown in the table.

Table 22 In the rapidly solidified alloy ribbon B, the crystal grains are fairly large and fairly uniform. that Therefore, the magnetic properties of the obtained magnet were determined by the twin roll method shown in Example 30. This is an improvement over the magnet made from the rapidly solidified alloy ribbon C.

However, the magnet made from ribbon A has better properties. ing.

1 shaku 1 yu An alloy ingot consisting of R35,0wt%, Bo, 9wt%, and the balance Fe was produced. Prepared in the same manner as Example 2.

From this alloy, quenched alloy ribbons A and B were made by the deformed twin roll method and the twin roll method. Each prepared. From these rapidly solidified alloy ribbons A and B, the same method as in Example 31 was applied. Each of them manufactures a magnet.

Table 23 shows the magnetic properties of the obtained magnet.

Table 23 Phantom V Ryu In the same manner as described in Example 3, R40.0wt%, B1.1wt%, the balance An alloy ingot made of Fe77Co2oA13 was prepared. Is this ingot? Thin strips A and B were prepared using a modified twin-roll method and a twin-roll method. This rapid cooling Alloy ribbons A and B were each magnetically prepared in a manner similar to that described in Example 31. manufactured stone.

The magnetic properties of this magnet are shown in Table 24.

Table 24 The present invention has been described above with reference to embodiments in which Nd was mainly used as the rare earth metal component. . However, the present invention is also applicable to magnets using other rare earth metals as R. Needless to say, 0° Furthermore, transition metals other than Co and Ni can be used with Fe.

1 day x 1 day Figure 1 shows the average crushed particle size of the powder using the magnetic characteristics of the sintered magnet in Example 1. The figure shown together, Figure 2 shows the magnetic properties of the sintered magnet in Example 4 along with the thickness of the rapidly solidified alloy ribbon. figure, Figure 3 shows the magnetic properties of the sintered magnet in Example 5, which is the average of the crystals in the rapidly solidified alloy ribbon. Figure 4 shows the magnetic properties of the sintered magnet in Example 10 with the particle diameter. A diagram shown together with the R value in the alloy, Figure 5 shows the magnetic properties of the sintered magnet in Example 13 due to cobalt content in the transition metal component. Fig. 6 shows the magnetic properties of the sintered magnet in Example 16. Figure 7 is a diagram showing the average particle diameter of crystal grains in the body, and Figure 7 shows the sintered magnet in Example 19. A diagram showing the magnetic properties of the stone along with the heat treatment temperature of the rapidly solidified alloy ribbon. Figure 8 is Example 2. A cross-sectional view showing an apparatus for preparing the rapidly solidified alloy ribbon used in 2. FIG. 9 is a side view showing an apparatus for preparing a scale-like rapidly solidified alloy used in Example 22. , Figure 9a is an enlarged view of the part within circle A in Figure 9, and Figure 10 is the sintering of Example 23. Diagram showing the magnetic properties of the magnet along with the thickness of the rapidly solidified alloy, Figure 11 shows the preparation of scale-like rapidly solidified alloys used in Examples 26 to 29. 12(a), 12(b), and 12(c). is a diagram showing the microstructure of the alloy ingot, granules, and scales in Example 26, FIG. 13 is a diagram showing the magnetic characteristics of the sintered magnet along with the sintering temperature in Example 26, Figure 14 shows the apparatus for preparing rapidly solidified alloy ribbons used in Examples 30 to 32. FIG.

In the figure, 21 is a melting tube, 22 is an orifice, 23 is a molten alloy, 24 is a roll, 25 and and 25' are holding roll cases, and 26 and 26' are rotating shafts 27 and 27', which are rotary shafts. 31 is a molten tube, 32 is an orifice, 33 is a molten alloy, and 34 is a roll-shaped permanent magnet. Roll, 35 is a protrusion, 36 is a plate, 37 is a cooling plate, 38 is a rotating shaft, 41 is a melting tube , 42 is a spray nozzle, 43 is a molten alloy, 44 is a cooling plate, and P is an atomized particle. , F is a small piece, 51 is a molten tube, 52 is an orifice, 53 is a molten alloy, 54 and 55 is a roll, and 56 is a rapidly solidified alloy ribbon.

Margin below Average crushed particle size (μm) FIG.1 FIG.2 Average crystal particle diameter (μm) R value of rapidly solidified alloy (wt%) C1ρ　l (Fe　+oo-工゛CO phantom FIG.5 F I G, 6 FIG.7 F I G, 8 10-1 Scale-like rapidly solidified alloy by jetting method Thickness of rapidly solidified alloy (μm) FIG. 10 FIG. 11 + Use of scales Use of Ichigoi granules Sintering temperature (C) FIG. 13 FIG. 14 international search report international search report Jρ8700917

Claims (1)

[Claims] 1. a preparation step of preparing R-T-B alloy powder containing R2T14B crystal particles; A molding process in which powder is charged into a magnetic field to form a molded object of a desired shape, and the molded object is In the method of manufacturing a sintered magnet by a sintering step of sintering at a sintering temperature, R-T-B alloy powder is Prepare a molten R-T-B alloy, The molten metal is rapidly cooled so that the crystal particles having a predetermined average particle size are uniformly dispersed. and each quenched ribbon and/or flaky quenched alloy having a predetermined thickness has a thickness The above-mentioned quenched alloy ribbon and/or scaly quenched alloy are formed to have a thickness smaller than the above-mentioned thickness. manufactured by grinding into a powder with an average particle size larger than the average particle size listed above. , each particle of said powder has crystal grains extending in one direction, thereby making said powder A rare earth metal characterized by being able to be magnetically oriented in the above magnetic field. A method for producing a metal-iron-boron anisotropic sintered magnet. 2. A method for producing a rare earth metal-iron-boron anisotropic sintered magnet according to the first claim. Each of the scale-like rapidly solidified alloys has a thickness of 20 to 50 μm, and the crystal grains have a thickness of 20 to 50 μm. is a rare earth metal-iron-boron material having an average particle size of 10 μm or less. A method for manufacturing a oriented sintered magnet. 3. A method for producing a rare earth metal-iron-boron anisotropic sintered magnet according to the second claim. Each of the quenched alloy ribbon and/or flaky quenched alloy has a thickness of 50 to 500 μm. Method for producing rare earth metal-iron-boron anisotropic sintered magnet characterized by having a thickness Law. 4. A method for producing a rare earth metal-iron-boron anisotropic sintered magnet according to the second claim. and the rare earth crystal particles have an average particle diameter of 1 to 10 μm. A method for manufacturing a metal-iron-boron anisotropic sintered magnet. 5. A method for producing a rare earth metal-iron-boron anisotropic sintered magnet according to the second claim. The pulverized powder is characterized in that it has an average particle size of 0.3 to 15 μm. A method for producing a rare earth metal-iron-boron anisotropic sintered magnet. 6. A method for producing a rare earth metal-iron-boron anisotropic sintered magnet according to the fifth claim. The pulverized powder is a rare powder having an average particle size of 1.5 to 7 μm. A method for manufacturing an earth metal-iron-boron anisotropic sintered magnet. 7. A method for producing a rare earth metal-iron-boron anisotropic sintered magnet according to the fifth claim. The sintering is performed so that the crystal particles grow to a particle size of 7 to 30 μm. 1. A method for producing a rare earth metal-iron-boron anisotropic sintered magnet. 8. A method for producing a rare earth metal-iron-boron anisotropic sintered magnet according to the first claim. The R-T-B alloy powder has R28.0 to 65.0% by weight, the balance T and A method for producing a rare earth metal-iron-boron anisotropic sintered magnet characterized by comprising B. . 9. A method for producing a rare earth metal-iron-boron anisotropic sintered magnet according to the eighth claim. The above R-T-B alloy powder contains R30-40% and B0.8-1.3% by weight. , the balance T. Construction method. 10. A method for producing a rare earth metal-iron-boron anisotropic sintered magnet according to the eighth claim. The transition metal component T in the R-T-B alloy is Fe1-xCox (x is Rare earth metal characterized by consisting of Fe and Co represented by 0.35 or less) A method for manufacturing an iron-boron anisotropic sintered magnet. 11. A method for producing a rare earth metal-iron-boron anisotropic sintered magnet according to the first claim. In the quenching step, the molten R-T-B alloy is passed through a small orifice. The liquid is injected onto the outer peripheral surface of a quenching roll rotating at a predetermined peripheral speed, and The above-mentioned injected molten metal is quenched into a quenched alloy ribbon and/or a scaly quenched alloy. A method for producing a rare earth metal-iron-boron anisotropic sintered magnet, characterized in that: 12. Method for manufacturing a rare earth metal-iron-boron anisotropic sintered magnet according to the eleventh claim , a magnetic field is applied in the radial direction of the roll and therefore the ejected beam Rare earth metal-iron-boron anisotropy characterized in that molten gold is cooled in the above magnetic field. A method for producing a sintered magnet. 13. Method for manufacturing a rare earth metal-iron-boron anisotropic sintered magnet according to the eleventh claim In this case, the above-mentioned quenching roll has a large number of protrusions formed on its outer surface, and the cooling roll is A plate is placed close to the quenching roll, and the outer circumferential surface of the quenching roll is The molten alloy injected into the cooling plate is sprayed onto the cooling plate to form a flat, scaly, rapidly solidified alloy. 1. A method for producing a rare earth metal-iron-boron anisotropic sintered magnet, comprising: 14. Method for manufacturing a rare earth metal-iron-boron anisotropic sintered magnet according to the thirteenth claim In the above, each flat flake-like rapidly solidified alloy has a thickness of 7 to 500 μm. A method for producing a rare earth metal-iron-boron anisotropic sintered magnet. 15. A method for producing a rare earth metal-iron-boron anisotropic sintered magnet according to the first claim. In this step, the R-T-B alloy molten metal is sprayed onto the cooling plate through a nozzle, and the R-T-B alloy melt is sprayed onto the cooling plate. A rare earth that is rapidly cooled on a cooling plate to form a flat, flake-like rapidly solidified alloy. A method for manufacturing a metal-iron-boron anisotropic sintered magnet. 16. Method for manufacturing a rare earth metal-iron-boron anisotropic sintered magnet according to the eleventh claim , the molten alloy is quenched by contacting the outer peripheral surface of the quench roll to form a quenched alloy. After forming the ribbon, the outer surface of the quenched alloy ribbon is brought into contact with another quench roll. Rare earth metal-iron-boron characterized by obtaining a rapidly solidified alloy ribbon by A method for producing anisotropic sintered magnets. 17. A method for producing a rare earth metal-iron-boron anisotropic sintered magnet according to the sixteenth claim , the rapidly solidified alloy ribbon has a thickness of 20 to 1000 μm. A method for producing a rare earth metal-iron-boron anisotropic sintered magnet. 18. A method for producing a rare earth metal-iron-boron anisotropic sintered magnet according to the first claim. In this case, the rapidly solidified alloy ribbon and/or the flaky rapidly solidified alloy are heated at a temperature of 650 to 950°C. Production of rare earth metal-iron-boron anisotropic sintered magnet characterized by being heat-treated with Method.