JP2017188690A - Manufacturing method of bond magnet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method of a bond magnet which has a high magnetization property, widens an adjustment range of a magnetization property, is simplified and reduces cost.SOLUTION: A manufacturing method of a bond magnet includes: a heating step for disposing magnetic field application means for magnetization in the vicinity of the bond magnet and making a temperature of the bond magnet rise equal to or higher than its Curie point; and a magnetization step for continuously applying a magnetization magnetic field to the bond magnet by the magnetic field application means for magnetization while making the temperature of the bond magnet that reaches a temperature equal to or higher than the Curie point, fall to a temperature lower than the Curie point. A magnet powder containing Nd and Pr as rare earth elements is used for the bond magnet. When adjusting a magnetization property of the bond magnet, a conditioning temperature that is an extraction temperature during cooling is adjusted, and the magnetic field application means for magnetization includes a permanent magnet for magnetization of which the Curie point is higher than that of the bond magnet.SELECTED DRAWING: Figure 6

Description

  The present invention relates to a method for manufacturing a multi-pole magnetized bonded magnet.

  Corresponding to the recent remarkable downsizing of electronic devices, stepping motors and the like used therefor have also been reduced in size and diameter. Accordingly, the diameter of the ring-shaped permanent magnet used as the rotor is also reduced, so that the magnetization pitch (distance between the magnetic poles) is narrowed and multi-pole magnetization becomes difficult.

As a method for magnetizing a multipole magnetic pole, pulse magnetization is known. In pulse magnetization, when a ring-shaped permanent magnet is magnetized, a large pulse current is passed through the magnet wire. However, if the magnetizing pitch becomes narrower as the diameter of the ring-shaped permanent magnet becomes smaller, As a result, the problem that the pulse current that can sufficiently magnetize the magnet cannot flow has arisen. As a technique for improving this, there is known a method of magnetizing an object to be magnetized by reducing the saturation magnetization field to a high temperature below the Curie point of the object to be magnetized (for example, Patent Document 1 and Patent Document). 2).
Further, regarding a method for magnetizing a permanent magnet, a method for magnetizing a permanent magnet that continuously applies a magnetizing magnetic field while lowering the temperature of a magnetic object from a temperature above its Curie point to a temperature below its Curie point. Is known (see, for example, Patent Document 3).

Japanese Patent No. 2940048 JP-A-6-140248 JP 2006-203173 A

However, the magnetization methods of Patent Document 1 and Patent Document 2 cannot provide sufficient magnetization characteristics. Further, since energization is performed to the magnet wire of the magnetized coil, the possibility of dielectric breakdown is inevitable. Furthermore, exposure to high temperatures degrades the components of the magnetizing jig, particularly the mold resin, and shortens the life of the magnetizing jig.
In the magnetizing method of Patent Document 3, high magnetization characteristics can be obtained in an Nd—Fe—B based bonded magnet. However, since the adjustment range of the magnetization characteristics depends on the physical properties of the magnetic powder, it is generally narrow and desired. It is difficult to obtain the magnetization characteristics. In addition, in response to soaring rare earth prices, there is an increasing demand for rare earth bonded magnets that exhibit high performance at a lower cost.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a simple and cost-effective method of manufacturing a bonded magnet that has a wide range of adjustment of the magnetization characteristics while having high magnetization characteristics. There is.

  In order to achieve the above-described object, the manufacturing method of the bonded magnet according to the present invention includes a heating step of disposing the magnetic field applying means for magnetization in the vicinity of the bonded magnet and raising the bonded magnet to a temperature equal to or higher than its Curie point. A magnetizing step of continuously applying a magnetizing magnetic field to the bond magnet by the magnetizing magnetic field applying means while lowering the temperature of the bond magnet that has reached a temperature above the Curie point to a temperature below the Curie point; A bonded magnet manufacturing method comprising: a magnetic powder containing Nd and Pr as rare earth elements in the bonded magnet, and adjusting a magnetization characteristic of the bonded magnet; The temperature control is adjusted, and the magnetizing magnetic field applying means includes a magnetizing permanent magnet having a Curie point higher than that of the bond magnet.

  By including two or more rare earth elements, the refining cost is reduced, and a simple and cost-effective method for producing a bonded magnet is obtained.

In the method for manufacturing a bonded magnet according to the present invention, the total amount of the rare earth elements is preferably 12 at% or more.
By setting the total amount of rare earth elements to 12 at% or more, a method for producing a bonded magnet having excellent magnetostatic characteristics, particularly squareness and coercive force, and high magnetization characteristics can be obtained.

In the method for manufacturing a bonded magnet according to the present invention, the magnet powder preferably has an intrinsic coercive force of 716 kA / m (9 kOe) or more.
By using a magnet powder having an intrinsic coercive force of 716 kA / m (9 kOe) or more, a method for producing a bonded magnet having excellent thermal demagnetization characteristics and very low initial demagnetization characteristics can be obtained.

The bonded magnet manufacturing method according to the present invention is characterized in that Nd and Pr are included as the rare earth element.
By including Nd and Pr as rare earth elements, final refining can be omitted as much as possible, the cost can be reduced, and high magnetostatic properties can be obtained. Therefore, the manufacturing method of the bonded magnet of the high magnetization characteristic which reduced the cost is obtained. In addition, the adjustment range of the magnetizing characteristics can be widened by utilizing the physical property that the thermal demagnetizing characteristics slightly decrease. Therefore, it is possible to obtain a method of manufacturing a bonded magnet that is highly magnetized and that has a wider characteristic adjustment range and that is simple and cost-effective and can be widely used industrially.

In the method for manufacturing a bonded magnet according to the present invention, the blending ratio of Nd and Pr is preferably 5 at% to 50 at% in terms of the Pr substitution amount with respect to the Nd amount.
Since Nd and Pr have magnetically similar physical properties, degradation of the magnetostatic characteristics can be minimized. If the blending ratio of Nd and Pr is 5 at% to 50 at% as the substitution amount of Pr with respect to the Nd amount, the refining burden is reduced to be close to the ratio produced in nature, and the cost can be reduced. The upper limit of 5 at% is a lower limit value for effect expression, and the upper limit of 50 at% is for suppressing a significant decrease in magnetic properties.
In addition, although the thermal stability is slightly lowered due to the mixing of Pr, it can be used as a characteristic adjusting means.
Further, since the Curie point is lowered, the set temperature of the magnetizing device can be lowered, the load on the device is reduced, and the magnetized object having a large heat capacity can be dealt with. Therefore, the manufacturing process as a whole has an effect of reducing the cost, and a relatively large magnet can be magnetized.
Therefore, it is possible to obtain a simple and cost-effective method of manufacturing a bonded magnet that can obtain higher magnetization characteristics and a wide characteristic adjustment range.

In the bonded magnet manufacturing method according to the present invention, it is preferable that the rare earth iron-based magnet does not contain Co.
By not containing Co, the magnet material price can be reduced, the Curie point can be lowered, and the thermal demagnetization characteristics can also be lowered, so that it is possible to obtain a bonded magnet with high magnetization characteristics at a reduced cost. When the heating temperature is relatively low, the burden on the apparatus is reduced and the characteristics can be easily adjusted. Furthermore, it is possible to relatively easily magnetize a magnet having a large heat capacity. Therefore, it is possible to obtain a simple and cost-effective method of manufacturing a bonded magnet that can obtain higher magnetization characteristics and a wide characteristic adjustment range.

  According to the present invention, an industrially useful bond magnet (high magnetic force characteristic, relatively large magnetization characteristic adjustment width, low cost) can be obtained by utilizing a decrease in Curie temperature or a decrease in thermal demagnetization characteristic. Can do.

(A) is a top view of the magnetization jig | tool and bond magnet in embodiment, (b) is a longitudinal cross-sectional view. The top view which shows the condition of the multipolar magnetization currently given to the bond magnet. The figure which shows an example of the measurement result of the surface magnetic flux density of 10 pole magnetization. The figure which showed the magnetization characteristic of Example 1, Example 2, and the comparative example 1. FIG. The figure which showed the magnetization characteristic of Example 1, Example 2, and Comparative Example 3. FIG. The figure which showed the magnetization characteristic of Example 1, Example 2, the comparative example 3, and the comparative example 4. FIG. The figure which showed the magnetization characteristic reduction rate in higher temperature on the basis of the magnetization characteristic in the temperature control temperature of 50 degreeC. The figure which showed the magnetization characteristic of Example 1, Example 2, the comparative example 3, and the comparative example 4. FIG. The figure which showed the magnetization characteristic of Example 1, the comparative example 5, and the comparative example 6. FIG.

Hereinafter, the manufacturing method of the bonded magnet of the present invention will be described in detail by taking an embodiment as an example.
FIG. 1 shows a magnetizing jig 10 used in the method for manufacturing a bonded magnet according to the embodiment and a bonded magnet 14 as an object to be magnetized. (A) represents a plan view, and (b) represents a longitudinal sectional view. In the embodiment, the ring-shaped bond magnet 14 is magnetized by 10 poles to obtain a multi-pole magnetized bond magnet 140.

The magnetizing jig 10 includes a non-magnetic block (for example, a stainless steel block) 12 provided with a circular magnetized material receiving hole 16 into which a bonded magnet 14 can be inserted and extracted, and a magnetized material stored therein. Ten grooves 18 having a rectangular section extending radially from the outer surface of the hole 16 are provided at equiangular intervals. In the grooves 18, magnetized permanent magnets 20 are embedded as rod-shaped magnetizing magnetic field applying means having a square cross section having a Curie point higher than that of the bonded magnets 14.
For example, an SmCo sintered magnet having a Curie point of about 850 ° C. can be used as the permanent magnet 20 for magnetization.

Below, the method to manufacture the bond magnet 140 magnetized by the multipole from the bond magnet 14 will be described.
In the manufacturing method of the bond magnet 140, the permanent magnet 20 for magnetization is disposed in the vicinity of the bond magnet 14, and the heating process for raising the bond magnet 14 to a temperature above its Curie point and the temperature above the Curie point are reached. A magnetizing step in which the magnet is continuously applied to the bond magnet 14 by the magnetizing permanent magnet 20 while the temperature of the bond magnet 14 is lowered to a temperature lower than the Curie point.

As the bonded magnet 14, a rare earth iron-based bonded magnet containing two or more rare earth elements is used. By including two or more kinds of rare earth elements, the refining cost can be reduced, and an inexpensive rare earth iron-based bonded magnet can be provided.
Table 1 shows the magnetic characteristics of the rare earth iron boron magnet (R2Fe14B). For example, a rare earth iron-based bond magnet in which a part of Nd having the highest saturation magnetization is partially substituted with an element exhibiting magnetic characteristics close to Nd, such as Y, Ce, and Pr, within a range where the influence on the magnetic characteristics is small is used. .
Here, a combination that is as close to the form as possible is preferable in terms of cost, and it is preferable that elements having high magnetic properties are combined.
In particular, since Nd and Pr have magnetically similar physical properties, a decrease in magnetostatic characteristics can be minimized. The blending ratio of Nd and Pr is preferably 5 at% to 50 at%, more preferably 10 at% to 35 at%, as the substitution amount of Pr with respect to the Nd amount, and the cost can be reduced close to the ratio produced in nature.

In the heating step, the bonded magnet 14 is inserted into the magnetic object receiving hole 16 while being heated to the Curie point or higher.
In the magnetizing step, a magnetizing magnetic field is applied by the magnetizing permanent magnet 20. Then, the bonded magnet 14 is cooled to a temperature lower than the Curie point of the bonded magnet 14 while being installed in the magnetized jig 10, and then taken out from the magnetized jig 10. For example, when the Curie point of the bonded magnet 14 is Tc, it is particularly preferable to heat to a temperature of (Tc + 30 ° C.) or higher and then cool to a temperature of (Tc−50 ° C.) or lower in a magnetizing magnetic field.
For heating, for example, any means such as resistance heating, high-frequency heating, laser heating, high-temperature gas flow heating, and high-temperature liquid heating may be used, but a high-frequency heating method capable of heating in a short time is particularly preferable. . Cooling may be performed by any method such as natural cooling, forced cooling such as water cooling, air cooling, gas blowing, and heating temperature adjustment. When work in an inert atmosphere is required, an inert gas flow is performed. The bond magnet 14 and the multi-pole magnetized bond magnet 140 can be easily and quickly inserted into the magnetized object accommodation hole 16 of the magnetizing jig 10 by a moving mechanism (not shown), and magnetized. It is preferable that the object can be easily and quickly removed from the object accommodation hole 16.

  Through the steps described above, magnetic poles corresponding to the magnetized magnetic poles appear on the outer peripheral surface of the ring-shaped permanent magnet that is the bonded magnet 14, and the bonded magnet 140 that is multipolarly magnetized is obtained. FIG. 2 is a plan view showing the state of multipolar magnetization applied to a ring-shaped permanent magnet, which is a bonded magnet 140 that is multipolarly magnetized. Reference numeral 22 represents the direction of the magnetizing magnetic field.

The evaluation of the magnetization characteristics can be performed quantitatively by measuring the surface magnetic flux density with a teslameter.
FIG. 3 is a diagram in which the surface magnetic flux density (open) Bo [mT] with respect to the central angle [degree] is measured on the outer peripheral surface of the bond magnet 140 magnetized with multiple poles with an arbitrary point as a reference.
As shown in FIG. 3, the outer peripheral surface of the multi-pole magnetized bond magnet 140 is continuously measured by changing the surface magnetic flux density (open) Bo [mT] with respect to the central angle [degree] with respect to an arbitrary point. To do that. In the following examples, the average value of the Bo peak values (absolute values) of all poles was shown as the magnetization characteristic.

Below, an Example and a comparative example are given and it demonstrates in detail.
The bond magnet 14 used in the following examples and comparative examples is a compression-molded bond magnet having an outer diameter of 2.6 mm, an inner diameter of 1.0 mm, and a thickness of 3 mm, and the dimensions and weight are unified (that is, the density is equal). . And 10 pole magnetization (pole pitch 0.8mm) from the outer periphery is performed, and the magnetization characteristic is shown. The magnet powder was formed by pulverizing a quenched ribbon and mixing 2.5 wt% of an epoxy resin as a binder resin with respect to the magnet powder.
Magnetization was performed using a magnetizing jig 10 at a heating temperature of 380 ° C. for 3 seconds, cooled to a temperature adjustment temperature, and taken out after 6 seconds to obtain a multi-pole magnetized bond magnet 140.

In Example 1, Example 2, and Comparative Example 1 shown below, the temperature adjustment temperature was set to 50 ° C.
Example 1
A rare earth iron-boron bond magnet 14 in which the rare earth element was Nd—Pr was used, and the total amount of rare earth elements was 12 at%.
(Example 2)
A rare earth iron-boron bond magnet 14 in which the rare earth element was Nd—Pr was used, and the total amount of rare earth elements was 12.5 at%.
(Comparative Example 1)
A rare earth iron-boron bond magnet 14 in which the rare earth element was Nd—Pr was used, and the total amount of rare earth elements was 10.0 at%.

FIG. 4 is a diagram showing the magnetization characteristics of Example 1, Example 2, and Comparative Example 1.
In FIG. 4, it was found that when the total amount of rare earth elements is 12 at% or more, the effect of suppressing initial demagnetization is exhibited, and a bonded magnet 140 having high magnetization characteristics can be obtained.

In Example 1, Example 2, and Comparative Example 1 shown below, the temperature control temperature is changed.
Example 1
A rare earth iron-boron bond magnet 14 having a rare earth element Nd—Pr was used, and a magnetic powder having an intrinsic coercive force of 716 kA / m (9 kOe) was used.
(Example 2)
A rare earth iron-boron bond magnet 14 having a rare earth element Nd—Pr was used, and a magnetic powder having an intrinsic coercive force of 796 kA / m (10 kOe) was used.
(Comparative Example 1)
A rare earth iron-boron bond magnet 14 having a rare earth element Nd—Pr was used, and a magnetic powder having an intrinsic coercive force of 557 kA / m (7 kOe) was used.

FIG. 5 is a diagram showing the magnetization characteristics of Example 1, Example 2, and Comparative Example 1. In FIG. The horizontal axis indicates the temperature control temperature (° C.), and the vertical axis indicates the magnetization characteristic (mT).
In FIG. 5, by using a magnet powder having an intrinsic coercive force of 716 kA / m (9 kOe) or more, a bonded magnet 140 having excellent thermal demagnetization characteristics and very low initial demagnetization characteristics can be obtained. .

(Comparative Example 3)
A rare earth iron-boron bond magnet 14 with a rare earth element Nd was used, and a magnetic powder having an intrinsic coercive force of 716 kA / m (9 kOe) was used.
(Comparative Example 4)
A rare earth iron-boron bond magnet 14 with a rare earth element Nd was used, and a magnetic powder having an intrinsic coercive force of 796 kA / m (10 kOe) was used.

FIG. 6 is a graph showing the magnetization characteristics of Example 1, Example 2, Comparative Example 3 and Comparative Example 4 when the temperature control temperature is 50 ° C. FIG. 7 is a graph showing a decrease rate of the magnetization characteristic at a higher temperature control temperature with reference to the magnetization characteristic at a temperature control temperature of 50 ° C., which is the extraction temperature during cooling.
In FIG. 6, it was found that a bond magnet 140 having high magnetic properties can be obtained by including Nd and Pr as rare earth elements.
In FIG. 7, by utilizing the phenomenon that the thermal demagnetization characteristic slightly decreases, the adjustment range of the magnetization characteristic can be expanded. Specifically, the decrease rate of the magnetization characteristic at the temperature adjustment temperature on the high temperature side increases. I understood it.

FIG. 8 is a diagram showing the magnetization characteristics of Example 1, Example 2, Comparative Example 3, and Comparative Example 4. The horizontal axis represents the heating temperature (° C.), and the vertical axis represents the magnetization characteristics (%). The magnetization characteristic (%) represents a ratio to the maximum value of each material. Moreover, the temperature control temperature was 50 degreeC.
In FIG. 8, it can be seen that the decrease in the magnetization characteristics is suppressed even when the heating temperature is lowered as the Curie point is lowered. By lowering the Curie point, the set temperature of the magnetizing device can be lowered, and the burden on the device is reduced, which is effective in manufacturing. Furthermore, since the heating condition can be set to a lower temperature, it is possible to relatively easily magnetize a magnet having a large heat capacity.

(Comparative Example 5)
Comparative Example 5 was obtained by adding 2 at% Co to the bonded magnet 14 of Example 1.
(Comparative Example 6)
Comparative Example 6 was obtained by adding 5 at% Co to the bonded magnet 14 of Example 1.
Here, in both Comparative Example 5 and Comparative Example 6, the intrinsic coercive force was 716 kA / m (9 kOe).

FIG. 9 is a diagram showing the magnetization characteristics of Example 1, Comparative Example 5, and Comparative Example 6. In FIG. The horizontal axis represents the heating temperature (° C.), and the vertical axis represents the magnetization characteristics (%). The magnetization characteristic (%) represents a ratio to the maximum value of each material. Moreover, the temperature control temperature was 50 degreeC.
In FIG. 9, it can be seen that the magnetization characteristics are saturated at lower heating temperatures as the Co content decreases.
The addition of Co is essential in order to raise the Curie point and stabilize it thermally in rare earth iron-based magnets, but by not including Co, the magnet material price can be reduced and the Curie point can be lowered. Since the magnetic characteristics are also lowered, a rare-earth iron-based bonded magnet with high magnetization characteristics can be obtained at a low cost, and the apparatus load is reduced and the characteristics can be easily adjusted by setting the magnetization conditions to a relatively low heating temperature. Furthermore, it is possible to relatively easily magnetize a magnet having a large heat capacity.
Further, since Co is produced as a by-product of Cu or Ni production, the production amount may be affected by the price situation of Cu or Ni, and it cannot be said that the supply system is necessarily stable. Therefore, it is desirable to achieve desired characteristics and high magnetic force characteristics without using Co if possible.

  The present invention is not limited to the embodiment described above.

The above description is an example of magnetizing a ring-shaped permanent magnet, which is a magnetized object, from the outside. However, the present invention can be magnetized from the inside or from both the inside and outside, similarly to the magnetization from the outside. It can also be applied to. With these magnetizing methods, magnetic poles corresponding to the magnetized magnetic poles appear on the inner peripheral surface or both inner and outer peripheral surfaces of the ring-shaped permanent magnet that is the magnetized object.
In the present invention, in addition to the configuration in which the magnetic field applying means for magnetizing is installed in only one stage in the axial direction, a configuration in which the magnetizing magnetic field applying means is arranged in two stages on the upper and lower sides is possible.
Further, skew magnetization can be realized, for example, by tilting and arranging permanent magnets for magnetization.

Further, the shape and size of the bonded magnet, the type of magnet powder, the Curie point of the bonded magnet, the Curie point of the permanent magnet for magnetization, and the like other than the embodiment can be selected.
In addition, the present invention can be variously modified and implemented without departing from the scope of the invention.

In the following, the invention described in the scope of claims attached first to the application for the application that forms the basis of this divisional application will be added. The item numbers of the claims described in the appendix are as in the scope of the claims initially attached to the application for the application on which the divisional application is based.
<Claim 1>
Arranging magnetic field applying means for magnetizing in the vicinity of the bond magnet,
Heating the bond magnet to a temperature above its Curie point;
A magnetizing step of continuously applying a magnetizing magnetic field to the bond magnet by the magnetizing magnetic field applying means while lowering the temperature of the bond magnet that has reached a temperature equal to or higher than the Curie point to a temperature lower than the Curie point. A method for manufacturing a bonded magnet, comprising:
A method for producing a bonded magnet, comprising using a rare earth iron-based bonded magnet containing two or more rare earth elements in the magnet powder contained in the bonded magnet.
<Claim 2>
The method for manufacturing a bonded magnet according to claim 1, wherein the total amount of the rare earth elements is 12 at% or more.
<Claim 3>
The method for producing a bonded magnet according to claim 1, wherein the magnet powder has an intrinsic coercive force of 716 kA / m (9 kOe) or more.
<Claim 4>
The method for manufacturing a bonded magnet according to any one of claims 1 to 3, wherein the rare earth element includes Nd and Pr.
<Claim 5>
The blending ratio (at%) of Nd and Pr is 5 to 50 in terms of Pr substitution amount with respect to Nd amount, Production of bonded magnet according to any one of claims 1 to 4 Method.
<Claim 6>
The said rare earth iron-type magnet does not contain Co, The manufacturing method of the bonded magnet as described in any one of Claims 1-5 characterized by the above-mentioned.

The invention described in the claims immediately before the division of the application serving as the basis of this divisional application will be added below. The item numbers of the claims described in the appendix are as in the claims immediately before the division of the application that is the basis of this divisional application.
<Claim 1>
A heating step of disposing a magnetic field applying means for magnetizing in the vicinity of the bond magnet and raising the bond magnet to a temperature equal to or higher than its Curie point;
A magnetizing step of continuously applying a magnetizing magnetic field to the bonded magnet by the magnetizing magnetic field applying means while lowering the temperature of the bonded magnet that has reached a temperature equal to or higher than the Curie point to a temperature lower than the Curie point. A method of manufacturing a bonded magnet including:
The bonded magnet is made of a magnet powder containing Nd and Pr as rare earth elements, and the temperature adjustment temperature, which is the extraction temperature during cooling, is adjusted when adjusting the magnetization characteristics of the bonded magnet. A method of manufacturing a bonded magnet.
<Claim 2>
The method for producing a bonded magnet according to claim 1, wherein the magnetic coercive force of the magnet powder is 716 kA / m (9 kOe) or more.
<Claim 3>
3. The total amount of the rare earth elements is 12 at% or more.
The manufacturing method of the bonded magnet of description.
<Claim 4>
The blend ratio (at%) of Nd and Pr is 5 to 50 in terms of the Pr substitution amount with respect to the Nd amount, The production of the bond magnet according to any one of claims 1 to 3. Method.
<Claim 5>
The said magnet powder does not contain Co, The manufacturing method of the bonded magnet as described in any one of Claims 1-4 characterized by the above-mentioned.

10: Magnetizing jig, 12: Non-magnetic block, 14: Bond magnet, 16: Magnetized object accommodation hole, 18: Groove, 20: Permanent magnet for magnetization, 22: Direction of magnetizing magnetic field, 140: Many A pole magnetized bond magnet.

Claims (1)

A heating step of disposing a magnetic field applying means for magnetizing in the vicinity of the bond magnet and raising the bond magnet to a temperature equal to or higher than its Curie point;
A magnetizing step of continuously applying a magnetizing magnetic field to the bonded magnet by the magnetizing magnetic field applying means while lowering the temperature of the bonded magnet that has reached a temperature equal to or higher than the Curie point to a temperature lower than the Curie point. A method of manufacturing a bonded magnet including:
Using the magnetic powder containing Nd and Pr as rare earth elements in the bond magnet, the temperature adjustment temperature, which is the take-out temperature during cooling, is adjusted when adjusting the magnetization characteristics of the bond magnet,
The method for producing a bonded magnet, wherein the magnetic field applying means for magnetization includes a permanent magnet for magnetization having a Curie point higher than that of the bonded magnet.

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