CN108630370A - Permanent magnet, electric rotating machine and vehicle - Google Patents

Abstract

The present invention inhibits the coercitive reduction of permanent magnet.Permanent magnet is with composition formula：RN_X(Cr_pSi_qM_1‑p‑q)_ZIt indicates.Permanent magnet includes having to be selected from Th₂Ni₁₇Type, Th₂Zn₁₇Type and TbCu₇First phase of at least one crystal structure of type, and with selected from MgCu₂Type and PuNi₃Second phase of at least one crystal structure of type.The volume ratio of the total amount of second phase is below 5%.

Description

Permanent magnet, electric rotating machine and vehicle

The application is with the Japanese patent application 2017-056046 (applyings date：3/22/2017) based on, above-mentioned application is enjoyed Priority.The application includes the full content of above-mentioned application by quoting above-mentioned application.

Technical field

The present invention relates to permanent magnet, electric rotating machine and vehicles.

Background technology

As high performance permanent magnet, it is known that the rare earth element magnets such as Sm-Co based magnets and Nd-Fe-B based magnets.Rare earth Class magnet is applied to electric appliances and hybrid vehicle (the Hybrid Electric such as motor, loud speaker, metrical instrument Vehicle：) and electric vehicle (Electric Vehicle HEV：The vehicles such as EV).In recent years, to the miniaturization of various electric appliances It is required that improve, and the increase in demand of the motor used in HEV and EV.In order to cope with these requirements, it is desirable to develop with most Big magnetic energy product (BH_max) the permanent magnet for rising to target.

As the ferromagnetic material of the permanent magnet for obtaining higher performance, such as promising is rare earth element and Fe etc. The combination of transition metal element.Sm-Fe-N based materials have the high saturation and magnetic intensity being equal to Nd-Fe-B based materials and surmount The larger magnetic anisotropy of Nd-Fe-B based materials, it is therefore contemplated that the application as high-performance magnet.However, Sm-Fe-N based magnets Material has the shortcomings that thermally decompose when heating at about 550 DEG C or more of temperature.Therefore, Sm-Fe-N based materials can not lead to Oversintering and be densified.

For this point, it is proposed that following technical solution：By by the part Cr of the Fe of Sm-Fe-N based magnet materials It is replaced with Si, to improve heat decomposition temperature.Sm- (Fe, Cr, Si)-N system permanent magnet have high saturation and magnetic intensity, compared with Big magnetic anisotropy and high heat decomposition temperature, therefore its application is expected.However, if be intended to obtain highdensity Sm- (Fe, Cr, Si)-N system permanent magnet, then in the densification technique based on sintering, Sm- (Fe, Cr, Si)-N system permanent magnet It is thermal decomposited, the α-Fe phases for making coercivity reduce is precipitated.

Invention content

Embodiment project to be solved is to inhibit the coercitive reduction of permanent magnet.

Technical scheme applied to solve the technical problem

The permanent magnet of embodiment is with composition formula：RN_X(Cr_pSi_qM_1-p-q)_ZIndicate that (R is selected from rare earth element, Zr, Nb With at least one element of Hf, M is at least one element selected from Fe and Co, and X is the atomic ratio of satisfaction 0.5≤X≤2.0, and p is Meet the atomic ratio of 0.005≤p≤0.2, q is the atomic ratio of satisfaction 0.005≤q≤0.2, and Z is the atom of satisfaction 4≤Z≤13 Than).Permanent magnet includes having to be selected from Th₂Ni₁₇Type, Th₂Zn₁₇Type and TbCu₇First phase of at least one crystal structure of type, With with selected from MgCu₂Type and PuNi₃Second phase of at least one crystal structure of type.The volume ratio of the total amount of second phase exists 5% or less.

Description of the drawings

Fig. 1 is the figure of an example of the SEM observation images in the section for indicating permanent magnet.

Fig. 2 is the figure of an example for the X-ray diffraction pattern for indicating permanent magnet.

Fig. 3 is the figure of an example for the X-ray diffraction pattern for indicating permanent magnet.

Fig. 4 is the figure of an example for the X-ray diffraction pattern for indicating permanent magnet.

Fig. 5 is the figure of an example for the X-ray diffraction pattern for indicating permanent magnet.

Fig. 6 is the figure of an example for the X-ray diffraction pattern for indicating permanent magnet.

Fig. 7 is the figure of an example for the X-ray diffraction pattern for indicating permanent magnet.

Fig. 8 is the schematic diagram for the configuration example for indicating motor.

Fig. 9 is the schematic diagram for the configuration example for indicating variable magnetic flux motor.

Figure 10 is the schematic diagram for the configuration example for indicating generator.

Figure 11 is the schematic diagram for the configuration example for indicating vehicle.

Figure 12 is the schematic diagram for the configuration example for indicating vehicle.

(symbol description)

1 ... main phase, 2 ... secondary phases, 3 ... α-Fe phases, 21 ... Permanent Magnet motors, 22 ... stators, 23 ... rotors, 24 ... iron Core, 25 ... permanent magnets, 31 ... variable magnetic flux motors, 32 ... stators, 33 ... rotors, 34 ... iron cores, 35 ... fixed magnets, 36 ... variable magnets, 41 ... generators, 42 ... stators, 43 ... rotors, 44 ... turbines, 45 ... axis, 46 ... brushes, 100 ... railways Vehicle, 101 ... electric rotating machines, 200 ... automobiles, 201 ... electric rotating machines.

Specific implementation mode

Hereinafter, being described with reference to embodiments of the present invention.The component for indicating the same symbol indicates same component.Separately Outside, attached drawing is signal or conceptual, and proportionality coefficient of size between the relationship of the thickness and width of each section, part etc. is not Necessarily it is the same as the actual situation.In addition, even if indicate with a part in the case of, difference with reference to the accompanying drawings, sometimes also with Different size each other and proportionality coefficient indicates.

(first embodiment)

The example of the permanent magnet of embodiment is illustrated.Fig. 1 is the SEM in the section for indicating permanent magnet (Scanning Electron Microscope, scanning electron microscope) observes the figure of an example of image.Tissue shown in FIG. 1 Including main phase 1, secondary phase 2, α-Fe phases 3.Main phase 1 is that volume occupation rate is highest in each crystalline phase and amorphous phase in permanent magnet Phase.Secondary phase 2 is the volume occupation rate phase lower than main phase 1.Secondary phase 2 has the crystalline phase or amorphous phase different from main phase 1.α-Fe phases 3 It is the out-phase different from secondary phase 2.In addition, the quantity of main phase 1, secondary phase 2 and α-Fe phases 3 is not limited to quantity shown in FIG. 1.

The composition of the permanent magnet of embodiment is indicated with following composition formulas (1).

RN_X(Cr_pSi_qM_1-p-q)_Z…(1)

(in formula, R is at least one element selected from rare earth element, Zr, Nb and Hf.M is at least one selected from Fe and Co Element.X is the atomic ratio of satisfaction 0.5≤X≤2.0.P is the atomic ratio of satisfaction 0.005≤p≤0.2.Q is 0.005≤q of satisfaction ≤ 0.2 atomic ratio.Z is the atomic ratio of satisfaction 4≤Z≤13.)

In composition formula (1), R is at least one element selected from rare earth element, zirconium (Zr), niobium (Nb) and hafnium (Hf).As Rare earth element can be enumerated such as yttrium (Y), lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd) and samarium (Sm).As R, can use 1 kind of element can also use multiple element.R assigns magnet with larger magnetic anisotropy and higher coercivity.It is preferred that R 50 atom % or more are Sm.Preferably the 70 atom % or more of R are Sm.It, can be with good by using rare earth element as R Reproducibility improves the performance of permanent magnet, especially coercivity.

Nitrogen (N) is present in the lattice of main phase 1 and secondary phase 2.If containing nitrogen in lattice, lattice expands, electronic structure It changes.Thereby, the Curie temperature of permanent magnet, magnetic anisotropy and saturation magnetization improve.When R is 1, the original of nitrogen Son is than being 0.5 or more 2.0 or less.That is, X is the atomic ratio of satisfaction 0.5≤X≤2.0.More preferable X is satisfaction 1.0≤X≤1.5 Atomic ratio.In the case that X is less than 0.5, obtain with being unable to fully in permanent magnet containing effect caused by nitrogen.If X is big In 2.0, then the reductions such as saturation magnetization of permanent magnet.

The a part of of N can be by least one element substitution selected from hydrogen (H), boron (B) and carbon (C).As above-mentioned displacement Element can use a kind of element, can also use multiple element.Above-mentioned substitutional element shows effect same as above-mentioned nitrogen. But if excessively replacing nitrogen, the reduction etc. of the magnetic anisotropy of permanent magnet can be incurred.It is therefore preferable that the 50 of nitrogen are former Sub- % or less is by above-mentioned element substitution.

M is at least one element selected from iron (Fe) and cobalt (Co).As M, a kind of element can be used, can also be used Multiple element.M is the magnetized element for mainly undertaking permanent magnet.By comparing M is contained in large quantities, permanent magnet can be improved Saturation magnetization.But if the content of M is excessive, the equal precipitations of α-Fe, coercivity reduces.

It is preferred that the 50 atom % or more of M are Fe.The 70 atom % or more of more preferable M are Fe.Fe in M is particularly helpful to forever The raising of the intensity of magnetization of long magnet.By making permanent magnet contain the part that Co is used as M, the Curie temperature of permanent magnet carries The thermal stability of height, permanent magnet improves.In addition, the coercivity of permanent magnet also improves.

The a part of of M can be by selected from titanium (Ti), vanadium (V), tantalum (Ta), molybdenum (Mo), tungsten (W), manganese (Mn), nickel (Ni), zinc (Zn) and at least one element substitution of germanium (Ge).As substitutional element, a kind of element can be used, a variety of members can also be used Element.Replacing the element of a part of M contributes to magnetic characteristic, for example coercitive raising.But if excessively by a part of M Displacement, the then intensity of magnetization reduction of permanent magnet.It is therefore preferable that the 10 atom % or less of the 20 atom % or less of M, more preferable M By above-mentioned element substitution.

Chromium (Cr) or silicon (Si) make the heat decomposition temperature of R-M-N systems permanent magnet increase.Chromium (Cr) or silicon (Si) are mainly set The site shared by M in change owner phase.Cr can improve the thermal stability of crystal by changing the quantity of the d electronics in crystal.Si The thermal stability of crystal can be improved by reducing the size of lattice.It, can by making to contain both Cr and Si in permanent magnet The thermal stability of R-M-N systems permanent magnet is improved to the state that can be applicable in sintering circuit.

The content of Cr in permanent magnet relative to M and Cr and Si total content be 0.5 atom % or more, 20 atom % with Under (0.005≤p≤0.2).If the content of Cr is very few, effect is obtained with being unable to fully.If the content of Cr is excessive, can Incur the reduction of saturation magnetization of permanent magnet etc..The content of Cr is more preferably 3 originals relative to the total content of M and Cr and Si 18 atom % of sub- % or more or less.The content of Cr is more preferably 5 atom % or more 15 relative to the total content of M and Cr and Si Atom % or less.

The content of Si in permanent magnet relative to M and Cr and Si total content be 0.5 atom % or more, 20 atom % with Under (0.005≤q≤0.2).If the content of Si is very few, the effect of Si is obtained with being unable to fully.If the content of Si is excessive, The reduction of saturation magnetization of permanent magnet etc. can then be incurred.The content of Si is preferably 1 relative to the total content of M and Cr and Si Atom % or more 15 atom % or less.The content of Si is more preferably 1 atom % or more, 10 originals relative to the total content of M and Cr and Si Sub- % or less.

The total content of Cr and Si is preferably 5 atom % or more, 20 atom % or less relative to the total content of M and Cr and Si.Cr With the total content of Si 8 atom % or more, 15 atom % or less are more preferably relative to the total content of M and Cr and Si.

Main phase 1, which has, is selected from Th₂Ni₁₇Type, Th₂Zn₁₇Type and TbCu₇At least one crystal structure (the first phase) of type.It is main Phase 1 has such as Sm₂(Fe,Cr,Si)₁₇N₃Equal R- (M, Cr, Si)-N phases.

Secondary phase 2, which has, is selected from cubic crystal MgCu₂Type and hexagonal crystal PuNi₃At least one crystal structure (the second phase) of type.It is secondary Phase 2 is for example with Sm (Fe, Cr, Si)₂N phases and Sm (Fe, Cr, Si)₃N equal R- (M, Cr, Si)-N phases.With selected from MgCu₂Type And PuNi₃R- (M, Cr, the Si)-N phases of at least one crystal structure of type with be selected from Th₂Ni₁₇Type, Th₂Zn₁₇Type and TbCu₇ R- (M, Cr, Si)-N of at least one crystal structure of type is compared, and thermal stability is lower, so if there is a large amount of secondary phase 2, then the amount of precipitation increase of the α-Fe phases 3 caused by thermally decomposing, makes the coercivity of permanent magnet reduce.Therefore, in permanent magnet Secondary phase 2 and α-Fe phases 3 preferably it is less.

It is preferred that the volume ratio of the total amount of secondary phase 2 in permanent magnet is below 5%.By reducing secondary phase 2, by secondary phase 2 Thermal decomposition caused by α-Fe phases 3 production quantity reduce, the magnet characteristic such as coercivity can be improved.It is preferred that α-the Fe in permanent magnet The volume ratio of the total amount of phase 3 is below 5%.

The analysis of the composition of permanent magnet for example passes through inductive coupling light-emitting plasma (Inductively Coupled Plasma：ICP) emission spectrometry carries out.In the analysis of the composition of permanent magnet, using by magnet jet mill or ball mill The powder below of whole 3% (alloy powder) is accounted in terms of volume % etc. the powder that grain size is 10 μm or more is ground into.From gained 10 samples of random acquisition, analyze the sample in powder.After removing maximum value and minimum value in the measured value of analysis It is averaged, the composition as permanent magnet.

Main phase 1, secondary phase 2 and α-Fe phases 3 can for example pass through SEM-EDX (scanning electron microscope-energy dispersion X-ray light Spectrum, Scanning Electron Microscope-Energy Dispersive X-ray Spectroscopy), TEM-EDX (transmission electron microscope-energy dispersion X-ray spectrum Transmission Electron Microscope-Energy Dispersive X-ray Spectroscopy) the methods of determine.By TEM-EDX, by electron beam cover in main phase Part and Grain-Boundary Phase part etc., can quantify the constitution element ratio of each section, and can identify crystal structure.

The main phase 1, secondary phase 2, the identification method example of α-Fe phases 3 that use SEM-EDX are illustrated below.Obtain viewing surface The SEM image of 50 μm of 50 μ m of product.In SEM image, relative to the summation of R, M, Cr, Si, by R element ratio in 10 atom % It is defined as main phase 1 less than the continuum of 20 atom %, continuum of the R element ratio more than 20 atom % is determined Justice is secondary phase 2, and R element ratio is defined as α-Fe phases less than the continuum of 10 atom % and Fe ratios more than 90 atom % 3.In same field of view, by the main phase 1 defined in a manner described, α-Fe phases 3 and secondary phase 2 area ratio directly as body Product ratio calculates, which is defined as to the volume ratio of the secondary phase 2 in permanent magnet.Similarly by main phase 1, secondary phase 2 and α-Fe The area ratio of phase 3 is calculated directly as volume ratio, which is defined as to the volume ratio of the α-Fe phases 3 in permanent magnet. For each block of permanent magnet, calculated respectively by the process described above in 5 field of view secondary phase 2 volume ratio, Resulting value is defined as volume ratio, the α-Fe of the secondary phase 2 of the permanent magnet by the volume ratio of α-Fe phases 3 by its arithmetic average The volume ratio of phase 3.

The permanent magnet of the embodiment secondary phase 2 low by reducing thermal stability, can inhibit the precipitation of α-Fe phases 3, not Reduce it is coercitive in the case of improve permanent magnet density.For example, the permanent magnet of embodiment has 6.5g/cm³More than Density.The density of permanent magnet be measure respectively permanent magnet in an atmosphere in water quality, calculated by Archimedes method Go out.At this point, being calculated separately 10 times for every a sample, remove maximum value and minimum from the density of the permanent magnet of gained It is averaged after value, is defined as the density of permanent magnet.

Then, manufacturer's rule of the permanent magnet of embodiment is illustrated.First, the member containing specified amount is manufactured The alloy powder of element.Alloy powder is indicated with composition formula (2).In addition, a part of of alloy powder can be by selected from hydrogen, boron and carbon At least one element substitution.

R(Cr_pSi_qM_1-p-q)_Z…(2)

In composition formula (2), atomic ratio Z is the number of satisfaction 4≤Z≤13, element M, Cr, Si other than atomic ratio Z expressions R Ratio of the total content relative to R.Atomic ratio p is the number of satisfaction 0.005≤p≤0.2.Atomic ratio q be 0.005≤q of satisfaction≤ 0.2 number.

Obtained by alloy powder for example can be by being cast the melt obtained by arc melting process or high frequency fusion method Alloy cast ingot is crushed by alloy thin band made from melt quenching method to prepare.Other preparation sides as alloy powder Method can enumerate mechanical alloying method and mechanical milling method, gas atomization, reduction-diffusion process etc..

The crushing of alloy cast ingot or alloy thin band etc. is preferably implemented to making the grain size of alloy powder reach 45 μm or less.Such as The grain size of fruit alloy powder at 45 μm hereinafter, in following nitrogen treatment nitrogen can then fully invaded to inside particles, because This can carry out entire particle the nitrogen treatment of homogeneous.The crushing of alloy cast ingot or alloy thin band etc. is for example using jet mill or ball Grinding machine is implemented.The crushing of the oxidation of alloy powder in order to prevent, alloy cast ingot or alloy thin band etc. is preferably in inert gas gas The medium progress of atmosphere.

Homogenize process is implemented to the alloy before alloy powder or crushing.If in Fe-Sm binary system state diagrams SmFe₃Fusion temperature be 1010 DEG C, then it is assumed that the heat treatment that homogenizes is carried out under such as 1000 DEG C or more of heat treatment temperature. However, in the permanent magnet of embodiment, because a part of Fe is replaced by Cr, Si, several variations occur for state diagram Possibility is high.Therefore, optimum treatment temperature may be down to 1000 DEG C or less.

In the homogenize process of embodiment, higher than 900 DEG C and low in a vacuum or in the inert gas atmospheres such as argon gas Heat treatment in 10~100 hours is carried out at a temperature of 1000 DEG C.Heat treatment temperature is below at 900 DEG C, element Diffusion may not proceed sufficiently, and alloy can not homogenize.Heat treatment temperature is formed in the case of 1000 DEG C or more in alloy With selected from cubic crystal MgCu₂Type and hexagonal crystal PuNi₃The phase of at least one crystal structure of type, as a result, permanent magnet Coercivity reduces.In homogenize process, more preferably implement heat treatment in 20~80 hours at a temperature of 930~970 DEG C.

Fig. 2 to Fig. 4 is the X of the X-ray diffraction measure for the permanent magnet for indicating that the manufacturing method by embodiment manufactures The figure of the example of ray diffraction pattern.Homogenize heat treatment heat treatment temperature be 900 DEG C, the feelings that heat treatment time is 65 hours Under condition, generates indicate that there is PuNi as shown in Figure 2₃Phase (the also referred to as PuNi of type crystal structure₃Phase) peak, homogenize heat treatment Heat treatment temperature be 1000 DEG C, in the case of heat treatment time is 65 small, generate indicate that there is MgCu as shown in Figure 4₂Type Phase (the also referred to as MgCu of crystal structure₂Phase) peak.Homogenize heat treatment heat treatment temperature be 950 DEG C, heat treatment time is In the case of 65 is small, as shown in Figure 3 without indicating PuNi₃Phase and MgCu₂The peak of equal pair phase, can get the main phase of homogeneous.

Fig. 5 to Fig. 7 is the X of the X-ray diffraction measure for the permanent magnet for indicating that the manufacturing method by embodiment manufactures The figure of the example of ray diffraction pattern.Homogenize heat treatment heat treatment temperature be 950 DEG C, heat treatment time is 16 hours, 32 In the case of small, as shown in Figure 5,6 without indicating PuNi₃Phase and MgCu₂The peak of equal pair phase, can get the main phase of homogeneous.With It is opposite, in the case of the heat treatment temperature for the heat treatment that homogenizes is 950 DEG C, heat treatment time is 4 small, as shown in fig. 7, Matterization cannot be sufficiently carried out, and generated and indicated PuNi₃Phase and MgCu₂The peak of equal pair phase.It follows that the heat treatment that homogenizes Heat treatment time is preferably 10 hours or more.

Then, nitrogen treatment is implemented to alloy powder.In nitrogen treatment, in the nitrogen atmosphere of 0.1~100 atmospheric pressure In, heat treatment in 0.1~100 hour is carried out at a temperature of 300~900 DEG C.In order to improve R- (M, Cr, Si)-N phases of main phase Homogenieity, more preferably carried out under conditions of the pressure of nitrogen atmosphere is 0.5~10 atmospheric pressure, temperature is 450~750 DEG C 2~24 hours nitrogen treatment.The atmosphere when nitrogen treatment of alloy powder can also carry out generation using compound gas such as ammonia For nitrogen.By using the gas mixed with hydrogen by nitrogen or compound gas, nitridation reaction also can control.

It, can be by the nitrogen in ferromagnetic material by using the mixed gas of the compound gas such as ammonia or nitrogen and hydrogen A part replaced with hydrogen.It, can be in the alloy powder before nitrogen treatment in the case that the part carbon or boron of nitrogen are replaced In contain carbon or boron, can also realize containing for carbon or boron with carbon compound gas or boron compound gas etc..

Then, to the alloy powder (nitrification for being set in the mold in electromagnet mixing filling and implementing nitrogen treatment Bronze end) and mixing alloy powder, press molding on one side apply magnetic field while, the press-powder that thereby manufacture crystallographic axis is orientated Body.

Then, the sintering of powder compact is carried out.As sintering method, it is preferred to use discharge plasma sintering process.Electric discharge etc. Gas ions sintering in, it is believed that easily choosing property of electric current to powder particle surface flow, suitably on one side inhibit be applied to The thermic load of R- (M, Cr, Si)-N phases of main phase, makes permanent magnet densification on one side.

Sintering carries out preferably in vacuum atmosphere or in the inert gas atmospheres such as argon gas.When discharge plasma is sintered, lead to Crossing makes sintering temperature reach 400~700 DEG C, can get fine and close permanent magnet.When less than 400 DEG C, it can not obtain with enough The permanent magnet of density.If being higher than 700 DEG C, the thermal decomposition of permanent magnet occurs, generation α-Fe are equal in permanent magnet, Therefore the magnetic characteristic of permanent magnet significantly reduces.

Permanent magnet is can get through the above process.The magnetic characteristic of gained permanent magnet can use vibration sample type magnetic force to measure It is fixed.The measurement of remanent magnetization can carry out as described below.It is applied on the direction parallel with the direction of magnetization being orientated before sintering Add external magnetic field until+1600kA/m, then magnetic field is restored to zero, the value of the intensity of magnetization measured at this time is defined as permanently The remanent magnetization of magnet.Except the measurement of permanent magnet sample, for the nickel mark similar with the specimen shape measured Quasi- sample (sample known to the absolute value of the intensity of magnetization) is also separately similarly measured, and the absolute value of the intensity of magnetization is corrected.

(second embodiment)

The permanent magnet of first embodiment can be used for electric rotating machine, such as motor and generator.These electric rotatings Machine is at least made of stator (stator) and rotor (gyrator).

Fig. 8 is the configuration example of the Permanent Magnet motor for the electric rotating machine for being denoted as the permanent magnet using embodiment Figure.Permanent Magnet motor 21 is made of stator (stator) 22, rotor (gyrator) 23.Rotor is configured in stator 22 23.Stator 22 makes rotor 23 rotate.Rotor 23 is made of iron core 24 and the permanent magnet of embodiment 25.Based on permanent magnet 25 Characteristic etc., it can be achieved that the high efficiency of Permanent Magnet motor 21 and miniaturization, cost effective etc..Permanent Magnet motor 21 It is suitable as that the vehicles such as hybrid electric vehicle and the electric vehicle of the miniaturization of the high-output power of motor and motor is required to use Motor.

Fig. 9 is the figure of the configuration example for the variable magnetic flux motor for being denoted as electric rotating machine.Variable magnetic flux motor 31 by Stator 32, rotor 33 are constituted.Rotor 33 is configured in stator 32.Rotor 33 is by iron core 34, fixed magnet 35, variable magnet 36 It constitutes.Fixed magnet 35 and variable magnet 36 use the permanent magnet of embodiment.It will be in fixed magnet 35 and variable magnet 36 It is at least one be used for rotor 33.

The magnetic flux density (magnetic flux) of variable magnet 36 is variable.D in Fig. 9 indicates the direction of magnetization of variable magnet 36 (by S towards the direction of N).The direction of magnetization of the variable magnet 36 is known as D axis.The direction that D axis indicates is according to variable magnet 36 And it is different.The direction orthogonal with D axis is known as Q axis.The magnetic flux density (magnetic flux) of variable magnet 36 not by with variable magnet The influence of the Q shaft currents in magnetic field is generated in the orthogonal Q axis directions of 36 direction of magnetization (D axis directions).The magnetic flux of variable magnet 36 Density (magnetic flux) can only be changed by generating the D shaft currents in magnetic field in D axis directions.

Magnetization winding (not shown) is provided on rotor 33.By making electric current flow into the magnetization winding, be formed as its magnetic field Directly act on the structure of variable magnet 36.Although variable magnetic flux motor 31 is small-sized device, larger turn can be exported Square.Variable magnetic flux motor 31 is suitable as requiring the hybrid electric vehicle of the miniaturization of the high-output power of motor and motor With for motor vehicle motor such as electric vehicle.

Figure 10 is the figure for the configuration example for indicating generator.Generator 41 is by using the stator of the permanent magnet of embodiment 42, rotor 43, turbine 44, axis 45 and brush 46 are constituted.Rotor 43 is connect via axis 45 with turbine 44.Turbine 44 is supplied from outside It is rotated under the action of the fluid given.It, can also be dynamic by transmitting regeneration energy of vehicles such as automobile etc. as the replacement of turbine 44 State rotates that axis 45 is made to rotate.Axis 45 and the commutator (not shown) for the opposite side that turbine 44 is configured at relative to rotor 43 connect It connects.By the output of electromotive force that the rotation of rotor 43 generates as generator 41, via phase separation busbar and main transformer It is boosted up to system voltage, is then powered.Brush 46 makes the electricity release of 43 bands of rotor.

Generator 41 can be common any one of generator and variable flux generator.Rotor 43 is because of turbine 44 Electrostatic and with power generation generate shaft current and charge.

Above-mentioned electric rotating machine can for example be loaded into the rolling stock (an example of vehicle) of railway traffic.Figure 11 is to indicate The figure of an example of the rolling stock 100 with electric rotating machine 101.As electric rotating machine 101, can be used above-mentioned Fig. 8,9 it is electronic The generator etc. of machine, Figure 10.In the case of loading above-mentioned electric rotating machine as electric rotating machine 101, electric rotating machine 101 for example can be with As using from the supply that installs electric wiring electric power or from be loaded into rolling stock 100 secondary cell supply electric power come export drive The motor (motor) of power uses, and can also be used as kinetic energy being converted to electric power, the various loads into rolling stock 100 The generator (generator) supplied electric power uses.Efficient rotation as electric rotating machine by using embodiment Motor can be such that rolling stock travels energy savingly.

Above-mentioned electric rotating machine can also be loaded into the automobiles such as hybrid vehicle and electric vehicle (another example of vehicle).Figure 12 be the figure of an example for the automobile 200 for indicating to have electric rotating machine 201.As electric rotating machine 201, above-mentioned Fig. 8,9 can be used The generator etc. of motor, Figure 10.In the case of loading above-mentioned electric rotating machine as electric rotating machine 201, electric rotating machine 201 can be with It is used as the motor of the driving force of output automobile 200 or the kinetic energy of automobile 200 when driving is converted to the power generation of electric power Machine.

Embodiment

(embodiment 1)

Raw material is allocated to scale, reaches alloy powder composition, Sm shown in table 1 (Cr_0.08Si_0.03Fe_0.89)_8.3Composition.By deployed raw material in argon gas atmosphere arc-melting, alloy cast ingot is made.It will close Golden ingot casting carries out heat treatment in about 3 days in argon gas atmosphere at 950 DEG C, to carry out the heat treatment that homogenizes.It then, will with mortar Alloy cast ingot crushes, and obtains alloy powder.The sieve in 25 μm of aperture of alloy powder is sieved.Alloy powder is big at about 1 The heat treatment that 4 hours are carried out in the nitrogen atmosphere of air pressure, at 700 DEG C, to obtain nitro-alloy powder.By the nitridation of gained Alloy powder carries out orientation pressurization in magnetic field on one side, is filled into mold on one side, then to powder with pressure 1.0GPa, sintering The condition that 600 DEG C of temperature implements discharge plasma sintering, obtains permanent magnet.The composition of permanent magnet is magnetic shown in table 1 Iron forms.

Table 2 show the value of the volume ratio of the density of the permanent magnet of embodiment 1, coercivity and secondary phase.Coercivity with The relative value when coercivity of the permanent magnet of following comparative examples 1 is set as 100 indicates.According to the permanent magnet of embodiment 1 The volume ratio of SEM-EDX analysis results, secondary phase is 2% (with reference to table 2).

(embodiment 2~14)

Raw material is allocated to scale, so that alloy powder composition is reached and is worth shown in table 1.In addition to this by with implementation Permanent magnet is made in 1 identical method of example.The characteristic of evaluation gained permanent magnet similarly to Example 1.Table 2 show implementation The density of the permanent magnet of example 2~14, coercivity, secondary phase volume ratio value.

(comparative example 1)

Other than the heat treatment temperature that homogenizes is 1000 DEG C, permanent magnet is made by method same as Example 1. The characteristic of evaluation gained permanent magnet similarly to Example 1.Table 2 show the density of the permanent magnet of comparative example 1, coercive The value of the volume ratio of power, secondary phase.

[table 1]

	Alloy powder forms (atomic ratio)	Magnet forms (atomic ratio)
			Embodiment 1	Sm(Cr0.08Si0.03Fe0.89)8.3	SmN1.23(Cr0.08Si0.03Fe0.89)8.3
Embodiment 2	Sm(Cr0.05Si0.03Fe0.90Mn0.02)8.3	SmN1.25(Cr0.05Si0.03Fe0.90Mn0.02)8.3
			Embodiment 3	Sm(Cr0.08Si0.04Fe0.85Ni0.03)8.5	SmN1.46(Cr0.08Si0.04Fe0.85Ni0.03)8.5
Embodiment 4	Sm(Cr0.07Si0.03Fe0.86Zr0.04)8.4	SmN1.31(Cr0.07Si0.03Fe0.86Zr0.04)8.4
			Embodiment 5	Sm(Cr0.07Si0.02Fe0.89Nb0.02)8.3	SmN1.28(Cr0.07Si0.02Fe0.89Nb0.02)8.3
Embodiment 6	Sm0.90Pr0.10(Cr0.08Si0.04Fe0.88)7.1	Sm0.90Pr0.10N1.08(Cr0.08Si0.04Fe0.88)7.1
			Embodiment 7	Sm0.89Nd0.11(Cr0.08Si0.03Fe0.89)7.1	Sm0.89Nd0.11N1.10(Cr0.08Si0.03Fe0.89)7.1
Embodiment 8	Sm0.90Ce0.10(Cr0.08Si0.03Fe0.89)7.5	Sm0.90Ce0.10N1.20(Cr0.08Si0.03Fe0.89)7.5
			Embodiment 9	Sm0.88Pr0.12(Cr0.09Si0.03Fe0.85Zn0.03)7.0	Sm0.88Pr0.12N1.01(Cr0.09Si0.03Fe0.85Zn0.03)7.0
Embodiment 10	Sm0.81Pr0.09Nd0.10(Cr0.06Si0.05Fe0.89)7.1	Sm0.81Pr0.09Nd0.10N1.05(Cr0.06Si0.05Fe0.89)7.1
			Embodiment 11	SmB0.02(Cr0.10Si0.01Fe0.89)7.5	SmN0.63B0.02(Cr0.10Si0.01Fe0.89)7.5
Embodiment 12	SmB0.02(Cr0.11Si0.02Fe0.85Al0.02)7.8	SmN0.88B0.02(Cr0.11Si0.02Fe0.85Al0.02)7.8
			Embodiment 13	SmC0.01(Cr0.06Si0.02Fe0.92)8.0	SmN1.14C0.01(Cr0.06Si0.02Fe0.92)8.0
Embodiment 14	Sm(Cr0.10Si0.03Fe0.85Ti0.02)8.5	SmN1.30(Cr0.10Si0.03Fe0.85Ti0.02)8.5
			Comparative example 1	Sm(Cr0.08Si0.03Fe0.89)8.3	SmN1.25(Cr0.08Si0.03Fe0.89)8.3

[table 2]

Can be confirmed the low permanent magnet of the volume ratio of secondary phase (embodiment 1~14) densification to comparative example 1 In the case of the density of equal extent, have than 1 higher coercivity of comparative example.The reason is that thermal stability is lower than main phase Secondary phase amount it is few, the production quantities of α-Fe phases caused by the thermal decomposition by secondary phase is reduced, and coercivity improves.

It illustrates several embodiments of the invention, but these embodiments are enumerated only as example, is not to use To limit the scope of the present invention.These new embodiments can be implemented by various other modes, can not depart from invention Technological thought in the range of carry out it is various omit, displacement, change.These embodiments and modifications thereof are included in the model of invention It encloses in technological thought, and is also included in invention described in claim and its equivalent range.

The above embodiment can be summarized as following technical scheme.

(technical solution 1)

A kind of permanent magnet is with composition formula：RN_X(Cr_pSi_qM_1-p-q)_ZThe permanent magnet of expression,

(R is at least one element selected from rare earth element, Zr, Nb and Hf, and M is at least one element selected from Fe and Co, X is the atomic ratio of satisfaction 0.5≤X≤2.0, and p is the atomic ratio of satisfaction 0.005≤p≤0.2, and q is satisfaction 0.005≤q≤0.2 Atomic ratio, Z is the atomic ratio of satisfaction 4≤Z≤13；)

Wherein, including

With selected from Th₂Ni₁₇Type, Th₂Zn₁₇Type and TbCu₇First phase of at least one crystal structure of type, and

With selected from MgCu₂Type and PuNi₃Second phase of at least one crystal structure of type；

The volume ratio of the total amount of second phase is below 5%.

(technical solution 2)

Permanent magnet as described in technical solution 1, wherein the 50 atom % or more of the R are Sm.

(technical solution 3)

Permanent magnet as described in technical solution 1 or 2, wherein the 50 atom % or more of the M are Fe.

(technical solution 4)

Permanent magnet as described in any one of technical solution 1~3, wherein the 20 atom % or less of the M by selected from At least one element substitution of Ti, V, Ta, Mo, W, Mn, Ni, Zn and Ge.

(technical solution 5)

Permanent magnet as described in any one of technical solution 1~4, wherein the 50 atom % or less of the N by selected from H, At least one element substitution of B and C.

(technical solution 6)

Permanent magnet as described in any one of technical solution 1~5, wherein the density of the permanent magnet is in 6.5g/ cm³More than.

(technical solution 7)

Permanent magnet as described in any one of technical solution 1~6, wherein α-Fe phases in the permanent magnet it is total The volume ratio of amount is below 5%.

(technical solution 8)

A kind of electric rotating machine, wherein there is rotor and stator, the rotor or the stator to have in technical solution 1~7 Any one of them permanent magnet.

(technical solution 9)

Electric rotating machine as described in technical solution 8 is motor or generator.

(technical solution 10)

A kind of vehicle, wherein with the electric rotating machine described in technical solution 8 or 9.

(technical solution 11)

A kind of vehicle, wherein with the electric rotating machine described in technical solution 8, rotation, which is delivered to, is set to the rotation The axis of one end of motor.

Claims (10)

1. a kind of permanent magnet is with composition formula：RN_X(Cr_pSi_qM_1-p-q)_ZThe permanent magnet of expression,

R is at least one element selected from rare earth element, Zr, Nb and Hf, and M is at least one element selected from Fe and Co, and X is full The atomic ratio of foot 0.5≤X≤2.0, p is the atomic ratio of satisfaction 0.005≤p≤0.2, and q is the atom of satisfaction 0.005≤q≤0.2 Than Z is the atomic ratio of satisfaction 4≤Z≤13；

Wherein, including

With selected from Th₂Ni₁₇Type, Th₂Zn₁₇Type and TbCu₇First phase of at least one crystal structure of type, and

With selected from MgCu₂Type and PuNi₃Second phase of at least one crystal structure of type；

The volume ratio of the total amount of second phase is below 5%.

2. permanent magnet as described in claim 1, wherein the 50 atom % or more of the R are Sm.

3. permanent magnet as claimed in claim 1 or 2, wherein the 50 atom % or more of the M are Fe.

4. permanent magnet according to any one of claims 1 to 3, wherein the 20 atom % or less of the M by selected from Ti, V, at least one element substitution of Ta, Mo, W, Mn, Ni, Zn and Ge.

5. permanent magnet as described in any one of claims 1 to 4, wherein the 50 atom % or less of the N are by selected from H, B With at least one element substitution of C.

6. such as permanent magnet according to any one of claims 1 to 5, wherein the density of the permanent magnet is in 6.5g/cm³With On.

7. such as permanent magnet according to any one of claims 1 to 6, wherein the total amount of the α-Fe phases in the permanent magnet Volume ratio below 5%.

8. a kind of electric rotating machine, wherein there is rotor and stator, the rotor or the stator, which have in claim 1~7, appoints Permanent magnet described in one.

9. electric rotating machine as claimed in claim 8 is motor or generator.

10. a kind of vehicle, wherein with the electric rotating machine described in claim 8 or 9.