JPH03290903A - Rare earth-iron magnets and their manufacturing method - 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] [Purpose of the invention]

(Industrial Application Field) The present invention relates to rare earth-iron magnets used in rotors and stators of rotating machines, and also relates to rare earth-iron magnets used in manufacturing the rare earth-iron magnets. The present invention relates to a method of manufacturing a system magnet. (Prior art) -e, magnets used in rotors, stators, etc. of rotating machines are required to have a high residual magnetic flux density (Br) in order to improve the output of the rotating machine. . On the other hand, when a rotating machine is started, a large demagnetizing field is applied to the end of the magnet in the rotational direction and the magnet is demagnetized, which may result in a decrease in output. Therefore, for this purpose, it is required that the magnet inherently has a high coercive force (wHc). (Question B that the invention seeks to solve) By the way, in recent years, rare earth-iron magnets have been developed that have even better magnetic properties than conventional ferrite magnets, samarium cobalt magnets, etc. is given anisotropy by hot plastic working, so the higher the working rate, the higher the residual magnetic flux density, but the coercive force tends to decrease, so both the residual magnetic flux density and the coercive force There was a problem in that it was difficult to maintain a high value at the same time. (Object of the Invention) The present invention has been made in view of such conventional problems, and provides a rare earth iron magnet having a region with increased coercive force and a region with increased residual magnetic flux density. For example, when starting a rotating machine, the part to which a large demagnetizing field is applied has a high coercive force to prevent a drop in output, and the main body part has a high residual magnetic flux density. It is an object of the present invention to provide a rare earth-iron based magnet that can improve the output.

[Structure of the invention]

(Means for Solving the Problems) The rare earth-iron magnet according to the present invention has a region with increased coercive force, a region with increased residual magnetic flux density, and, if necessary, a region with magnetic properties intermediate between the two. In an embodiment, the composition of the magnet is the same in the region where the coercive force is increased and the region where the residual magnetic flux density is increased; The composition of the magnet is different between the region where the residual magnetic flux density is increased and the region where the residual magnetic flux density is increased, and the magnetic properties are anisotropic. Furthermore, the composition of the magnet is a rare earth-iron magnet of R-Fe-B yarn, and the general formula is R1-(x-β-γ{F
e (Ni, Mn, Co)). It is represented by XβMy, where R is one or more rare earth elements including Y, and X is B, C, N, or Si. One or more of P, M is TiZ r ,
Hf, V, Nb, Ta, Cr,
Mo, W. AM, Zn, Ga, In, Tu, Ru, Rh. One or more of Pd, Os, Ir, and Pt, 0.60≦α≦0.85゜0<β≦0.15,
The method for manufacturing a rare earth-iron magnet according to the present invention is characterized by having a structure in which O≦γ≦0.02, and when performing plastic working into a predetermined magnet shape, at least the processing rate in the plastic working is Using a pre-carrotation magnet material that has a shape that creates a part where the working rate is low and a part where the working rate is high in the same plastic working, plastic carving is applied to a predetermined shape, and the part where the working rate is low is made to have a high coercive force. A magnet having a composition that at least improves coercive force when plastic working is performed into a predetermined magnet shape. Plastically working a magnet material with a composition that improves the residual magnetic flux density into a predetermined shape, - forming a part using the magnet material with a composition that improves the coercive force in a region where the coercive force is increased; A structure is adopted in which a part using a magnet material having a composition that improves the residual magnetic flux density is formed in a region where the residual magnetic flux density is increased, and furthermore, when plastic working is performed into a predetermined magnet shape, at least the coercive force is improved. A pre-processed magnet using a magnet material having a composition that produces a portion where the processing rate is low in the plastic working and a magnet material having a composition that increases the residual magnetic flux density and having a shape that produces a portion where the processing rate is high during the plastic working. Plastically working the material into a predetermined shape, using a magnet material with a composition that improves the coercive force, and forming a portion where the processing rate is low in a region where the coercive force is increased, and improving the residual magnetic flux density. A structure in which a magnetic material with a certain composition is used and the part where the processing rate is high is formed in a region with increased residual magnetic flux density is called #molding, and in an embodiment, the plastic working temperature is 650-1000°C. It is characterized by having a configuration that is. (Function of the Invention) The rare earth-iron magnet according to the present invention has a structure having a region with increased coercive force and a region with increased residual magnetic flux density, so it can be used, for example, as a rotor or stator of a rotating machine. In this case, the output of the rotating machine can be improved by making the region with high residual magnetic flux density the main body of the magnet, and at the same time, by making the region with high coercive force the end portion of the magnet in the rotational direction, the rotating machine can be improved. At the time of startup, a large demagnetizing field is not applied to the end of the magnet in the rotating direction, thereby preventing a decrease in output. In the method for manufacturing a rare earth-iron magnet according to the present invention, when plastic working is performed into a predetermined shape, a magnet material is formed of a portion where the processing rate is low in the plastic working and/or a composition whose coercive force is improved. Since the pre-processing material is processed into a predetermined shape using a shape that has a part where the processing rate is high and/or a part made of a magnet material with a composition where the residual magnetic flux density is improved, the processing rate can be increased. The part where the magnetic flux is low and/or the part made of the magnet material with the composition where the coercive force is improved becomes a region where the coercive force is increased, and the part where the processing rate is high and/or the part where the composition is made of the magnet material where the residual magnetic flux density is improved. The rare earth-iron magnet according to the present invention is manufactured by forming the portion 1 in a region where the residual magnetic flux density is higher than that of the portion 1. (Example) Example 1 A molten metal of a rare earth-iron magnet alloy consisting of 30% by weight Nd, 0.5% by weight B, and the balance Fe was flaked by liquid quenching to obtain a flake containing amorphous or fine crystals. Ta. Next, the flakes are pulverized into powder. When plastic working is performed using this powder as a raw material into a predetermined magnet shape, as shown in FIG. An unprocessed magnet material 1 was obtained which was shaped to form a portion 1b. At this time, the thin part 1a where the processing rate is low
The wall thickness t1 of the thick portion 1b was set to 4.3 mm, and the wall thickness t2 of the thick portion 1b where the processing rate was high was set to 7.5 mm. Next, by heating the unprocessed magnet material 1 to 800° C. and performing hot plastic working, a magnet having a uniform thickness with an overall wall thickness t3 of 3.0 mm is produced as shown in FIG. 1(b). After obtaining the material, it was magnetized to obtain a rare earth-iron magnet 2. The rare earth-iron magnet 2 manufactured here has a region 2a with increased coercive force, which has a wall thickness of 4.3 mm before 71O machining and a machining rate of 30%, and a region 2a with an increased coercive force that has a wall thickness of 71 mm before machining. .5mm and a region 2b with increased residual magnetic flux density with a processing rate of 60%, and each of the! The feel was as shown in Table 1. As shown in Table s1, the rare earth-iron magnet 2 obtained in this example has an increased coercive force region 2a where the coercive force is larger and a residual magnetic flux where the residual magnetic flux density is larger. By using such a rare earth-iron magnet 2 as a component of a rotating machine, due to the presence of the region 2b with increased residual magnetic flux density, It has been found that it is possible to further improve the output, and the existence of the region 2a with increased coercive force makes it possible to reduce the decrease in output due to the demagnetizing field at the time of starting rotation. . Example 2 28% by weight Nd-2% by weight Dy-2, 5% by weight Co-1
A molten metal of a rare earth-iron magnet alloy consisting of , 0 wt% B, 0.5 wt% Ga, and the balance Fe is thinned by a liquid quenching method to form flakes containing amorphous or fine crystals, and then powdered to increase the coercive force. Magnet powder with a composition that improves the On the other hand, 30% by weight Nd-5ji amount% Co-1.0% by weight
B- A molten metal of a rare earth-iron magnet alloy consisting of the balance Fe was thinned by a liquid quenching method to form flakes containing amorphous or am crystals, and then powdered to obtain a magnet powder having a composition that improves the residual magnetic flux density. . Next, as shown in FIG. 2(a), a portion corresponding to the main body of the rare earth-iron magnet to be manufactured is made of magnet powder 3b having a composition that improves the residual magnetic flux density, and one end side (rotating When used as a machine part, a powder molded body 3 having a uniform thickness and a wall thickness t4 of 4.3 mm was obtained, in which the portion corresponding to the end side in the rotational direction was made of magnet powder 3a having a composition that improved the coercive force. Ta. Next, by heating the powder compact 3 to 800° C. and performing hot plastic working, a magnet material having a uniform thickness with an overall wall thickness t5 of 3.0 mm is obtained as shown in FIG. 2(b). After the magnet was obtained, it was magnetized to obtain a rare earth-iron magnet 2. The rare earth-iron magnet 2 manufactured here has a region 2 with increased coercive force using a magnet material with a composition that improves coercive force.
a, and a region 2b with increased residual magnetic flux density using a magnet material having a composition that improves residual magnetic flux density, and the magnetic properties of each are as shown in Table 2. As shown in Table 2, in the rare earth-iron magnet 2 obtained in this example, there is also a region 2a with increased coercive force where the coercive force is larger and a residual region where the residual magnetic flux density is larger. It was recognized that the magnetic flux had a region 2b with increased magnetic flux density.

【Effect of the invention】

Since the rare earth-iron magnet according to the present invention has a region with increased coercive force and a region with increased residual magnetic flux density, high coercive force and high residual magnetic flux density can be obtained at the same time. For example, when used as a magnet for a rotating machine, the presence of the region with high residual magnetic flux density makes it possible to improve the output of the rotating machine, and at the same time, the presence of the region with high coercive force makes it possible to improve the output of the rotating machine when starting the rotating machine. The extremely excellent effect of suppressing demagnetization due to the generation of a demagnetizing field and preventing deterioration of the output over time is brought about, and the method for manufacturing a rare earth-iron magnet according to the present invention When performing plastic working on the magnet shape, a part using a magnet material with a composition that improves the coercive force and/or a part where the processing rate is low in the plastic carroe and a magnet material with a composition that improves the residual magnetic flux density are used. A part and/or a part using a magnet material having a composition that improves the coercive force by plastic working into a predetermined shape using a pre-processed magnet material shaped to produce a part where the processing rate is high in the plastic working. Alternatively, the part where the machining rate is low is formed in a region where the coercive force is increased, and the part using a magnet material having a composition that improves the residual magnetic flux density and/or the part where the machining rate is high is formed in a region where the residual magnetic flux density is increased. Since the magnet is formed in the above-mentioned region, it is possible to produce a rare earth-iron magnet having the above-mentioned excellent characteristics, which is a significant effect.

[Brief explanation of the drawing]

FIG. 1 shows Example 1 of the present invention, FIG. 1(a) is an explanatory diagram showing the state before hot plastic working, and FIG. 1(b)
2 is an explanatory diagram of a rare earth-iron magnet after plastic working and magnetization, and FIG. 2 shows Example 2 of the present invention, and FIG. 2(a)
2(b) is an explanatory diagram showing the state before hot plastic working, and FIG. 2(b) is an explanatory diagram of the rare earth-iron magnet after plastic working and magnetization. 2... Rare earth-iron magnet, 2a... Region with increased coercive force, b... Region with increased residual magnetic flux density.

Claims (1)

[Scope of Claims] (1) A rare earth-iron magnet characterized by having a region with increased coercive force and a region with increased residual magnetic flux density. (2) The rare earth-iron magnet according to claim (1), wherein the composition of the magnet is the same in the region where the coercive force is increased and the region where the residual magnetic flux density is increased. (3) The rare earth-iron magnet according to item (1), wherein the composition of the magnet is different in the region where the coercive force is increased and the region where the residual magnetic flux density is increased. (4) The rare earth-iron magnet according to any one of claims (1), (2), and (3), wherein the magnetic properties are anisotropic. (5) The magnet is a rare earth-iron magnet with an R-Fe-B composition, and has the general formula R_1_-_α_-_β_-_γ{Fe(Ni, Mn,
Co)}_αX_βM_γ where R is one or more selected from rare earth elements including Y, and X is one or more selected from B, C, N, Si, and P. , M is Ti, Zr,
Hf, V, Nb, Ta, Cr, Mo, W, Al, Zn,
Ga, In, Tl, Ru, Rh, Pd, Os, Ir, P
One or more types selected from t, and 0
．． 60≦α≦0.85, 0<β≦0.15, 0≦γ≦0
．． Claims (1), (2), and (3) which are 02
or (4). (6) When performing plastic working into a predetermined magnet shape, the pre-processed magnet material is shaped to create a portion where the working rate is low in the plastic working and a portion where the working rate is high in the plastic working. A claim characterized in that the part where the working rate is low is formed in a region where the coercive force is increased, and the part where the working rate is high is formed in a region where the residual magnetic flux density is increased. Clause (1),
The method for manufacturing a rare earth-iron magnet according to any one of paragraphs (2), (3), (4), or (5). (7) When performing plastic working into a predetermined magnet shape, the coercive force is improved by plastic working into the predetermined shape using a magnet material with a composition that improves coercive force and a magnet material with a composition that improves residual magnetic flux density. A part using a magnet material having a composition that improves the residual magnetic flux density is formed in a region with an increased coercive force, and a part using a magnet material with a composition that improves the residual magnetic flux density is formed in a region with an increased residual magnetic flux density. Claim No. 1 characterized by
), (3), (4), or (5). (8) When performing plastic working into a predetermined magnet shape, use a magnet material with a composition that improves coercive force, and use a magnet material with a composition that improves residual magnetic flux density in areas where the processing rate is low in the plastic working, and Plastic working is performed into a predetermined shape using a pre-processed magnet material shaped to produce a portion where the processing rate is high in the plastic working, and a magnet material having a composition that improves the coercive force is used to create a portion where the processing rate is low. A claim characterized in that the magnetic material is formed in a region with an increased coercive force, and a magnet material having a composition that improves the residual magnetic flux density is used, and a portion where the processing rate is increased is formed in a region with an increased residual magnetic flux density. The method for manufacturing a rare earth-iron magnet according to any one of paragraphs (1), (3), (4), or (5). (9) The method for producing a rare earth-iron magnet according to any one of claims (6), (7), and (8), wherein the plastic working temperature is 650 to 1000°C.