CN1110426A - Multi-phase compound permanent-magnet material capable of regulating magnetic property step by step - Google Patents

Abstract

The present invention relates to the field of multiphase compound permanent-magnet material. Said invention discloses this new type multiphase compound permanent-magnet mateiral, and its expression can be referred to its patent specification. The invented material consists of barium and strontium permanent-magnet ferrites whose weight percentage range in said compound permanent-magnet alloy material is 0-70, adhesive material whose weight percentage range is 0-20 and rare-earth permanent-magnet material. The invented multi-phase compound permanent-magnet alloy contains two or more magnetic phases, and the weight-percentage of the ferrite permanent-magnet material of the compound material can be regulated, so that the magneitc property of said alloy material can be regulated stage by stage, and its cost performance is rational.

Description

Multi-phase compound permanent-magnet material capable of regulating magnetic property step by step

The present invention relates to composite material and field of multiphase compound permanent-magnet material.

Permanent magnetic material mainly is divided into following a few class at present: ferrite permanent-magnet, AlNiCo, rare-earth cobalt permanent magnet and rare-earth iron-boron permanent magnetism.Ferrite permanent-magnet is cheap, and magnetic energy product (BM) m is 0.5-4MGOe, belongs to the low performance permanent magnetic material, is present most widely used permanent magnetic material.But it is because magnetic energy product is low, thereby lower with the power device efficient of this kind material design.AlNiCo permanent magnetism has higher remanent magnetism (10-13KGS), lower coercive force (600-1500 Oe), and magnetic energy product is 6-13MGOe, is the casting magnet.Rare-earth cobalt permanent magnet has SmCo ₅And Sm ₂Co ₁₇Two kinds on type, belong to respectively first and second generation rare earth permanent magnet, its magnetic property is than the former two's height, Sm ₂Co ₁₇The magnetic energy product of type can reach 30MGOe, but because it contains rare expensive Sm and strategic resource Co, can not obtain stable supply, thereby price is expensive.Be difficult to extensive use.The rare-earth iron-boron permanent magnetic material is the highest permanent magnetic material of present magnetic energy product as third generation rare earth permanent magnet, and the magnetic energy product of NdFeB can reach 50MGOe.It replaces Sm because of resourceful Nd with relative Sm, replace Co with Fe, thereby price is cheap than SmCo.The NdFeB permanent magnetic material has obtained using widely since nineteen eighty-three comes out.At 1984-1985, General Motors Overseas Corporation obtains fast quenching NdFeB technology patent, and the SUMITOMO CHEMICAL metal company has obtained the sintering process patent.Its patent characteristic has all been emphasized with Nd ₂Fe ₁₄B is as the hard magnetic phase, and wherein Nd can part be replaced by rare earth elements such as Dy, Pr, and Fe can be partly by replacements such as Ti, Zr, Nb, Co, and B can be partly by replacements such as Si, C, Al.In order to satisfy the requirement of thermal stability, improve Curie point, still used rare expensive element Dy and strategic materials Co, but its content is more much lower than SmCo.As the big bonded permanent magnet of freedom shape, in the 5-12MGOe scope, seldom make anisotropic bonded magnet with neodymium iron boron.On price, the NdFeB material is compared still high times with ferrite at present, has also limited its application in many aspects." the 4th generation " rare earth permanent-magnetic material Sm of present development ₂Fe ₁₇Nx, its coercive force has reached 30KOe, and magnetic energy product can reach 12MGOe.Because technological problems also fails to solve at present, does not put goods on the market as yet.

Permanent magnetic material can be divided into sintering, casting magnet and bonded permanent magnet.Bonded permanent magnet is to adopt permanent-magnet powder and binding agent to be blended in die for molding.Bonded permanent magnet can only be made with ferrite and rare earth permanent magnet.The magnetic property of ferrite bonded permanent magnet is very low, and (BH) m is only between 0.1-2.0MGOe, and the magnetic energy product of isotropism NdFeB bonded permanent magnet is generally between 5-10MGOe, and the SmCo bonded permanent magnet can reach 5-17MGOe.At present, have only ferrite and SmCo magnet that the anisotropic bonded magnet mass marketed is arranged.In the magnetic of reality is used, the user to permanent magnetic material performance require of all kinds.As the intrinsic performance to magnet, the freedom shape of magnet all has different requirements with complexity of orientation etc., and will consider the price of magnet.For example, in some device application, need magnetic energy product between 3-5MGOe, difficult on craftwork manufacture separately by anisotropic ferrite, and use the NdFeB isotropic bonded magnet uneconomical separately.Thereby be between 3-5MGOe at magnetic energy product, the bonded permanent magnet with rational performance and price ratio also is short of.Again for example, in the application of motor, the anisotropy of magnet requires very high, requires to make progress in the footpath of motor, have strong magnetic field thereby form closed magnetic circuit, and the magnetic circuit that is out in the axial direction, flux loss is little, stray field is little, and therefore, magnet needs radial magnetizing.In magnetic energy product required the 5-14MGOe scope, ferrite was difficult to reach its lower limit, and AlNiCo is orientated on being difficult in radially.Anisotropy NdFeB magnetic yet there are no listing in enormous quantities, and the SmCo price is too high, and aspect bonded permanent magnet, this is again a vacancy.

As seen different application scenarios requires difference very big to magnetic property.Satisfy these requirements, only depend on the bonded permanent magnet of certain one-component to be difficult to accomplish.The neodymium iron boron patent of GM company and Sumitomo does not provide satisfied answer in this respect.

The objective of the invention is to: seek a kind of novel permanent magnetic material, use the composite theory of composite material, make it and to adjust magnetic property step by step according to application need, thereby have rational performance and price ratio, to fill up above-mentioned vacancy.

Purpose of the present invention has reached fully by following measure: according to the composite principle of physical property, adopt heterogeneous composite methods, ferrite permanent-magnet and rare earth permanent-magnetic material are combined into multi-phase compound permanent-magnet material, or compound with high anisotropy permanent magnetic material and ferrite permanent-magnet materials or isotropism rare-earth iron-boron material, its magnetic property can be adjusted by different proportionings within the specific limits as required step by step.

Below multi-phase compound permanent-magnet material of the present invention is elaborated.

The invention discloses the type multi-phase compound permanent-magnet material, according to composite theory, the composite material of heterogeneous composition has simple linear additivity for most physical parameters such as density, proportion, modulus of elasticity, permeability.Find through experiment, on the binding electromagnetic material that this theory is equally applicable to be made up of two or more materials.Be magnetic energy product (BH) m of multi-phase compound permanent-magnet material, remanent magnetism Br, coercivity H also have simple linear additivity.Can be expressed as:

Kc= $\underset{i}{\overset{}{\mathrm{\Σ}}}$ p _iK _iV _i(i=2、3……n)

Wherein Ke is the magnetic physical quantity of multi-phase compound permanent-magnet material, K _iMagnetic physical quantity for the one pack system constituent element.V _iBe its volume fraction, P _iBe the volume fraction coefficient, it is relevant with factors such as phase boundary character and filling rates, can obtain according to experiment.Anisotropic constituent element and isotropism constituent element are compound, still can obtain the anisotropy tissue.

Instruct based on above-mentioned theory, behind the magnetic property of our known various one pack system permanent magnetic materials, can obtain best magnetic property combination, and can be within the specific limits magnetic property be carried out step by step adjustment by changing the volume fraction of each component permanent magnetic material.

Multi-phase compound permanent-magnet material disclosed in this invention, its feature is as follows:

Composite material is formed A=aX+bY+ $\underset{i}{\overset{}{\mathrm{\Σ}}}$ c _iZ _i(i=1,2……n)

Wherein, c _iBe Z _iThe volume fraction of constituent element, Z _iBe this constituent element rare earth permanent-magnetic material type.X is barium, strontium ferrite, and a is its volume fraction, and Y is a binder material, and b is its volume fraction.

The determined Z of the present invention _iFor:

Z1 is R ₂TM ₅Type and R ₂TM ₁₇The type rare earth permanent magnet.Z2 is R ₂TM ₁₄M type rare earth permanent magnet.Z3 is R ₂TM ₁₇Nx type rare earth permanent magnet.

Above-mentioned constituent element is isotropic material or anisotropic material, through special compound after, make heterogeneous plyability permanent-magnet alloy, coat through binding agent, and through mold pressing, calendering, the traditional diamond-making technique and the whole district or modern processing methods such as constituency sintering, the whole district or constituency bonding, the whole district or constituency extrusion molding, the whole district or constituency reaction-sintered such as inject, extrude and make bonded permanent magnet, can obtain magnetic energy product is the various trade mark bonded permanent magnets of 3-10MGOe.

Composite material magnet of the present invention is the heterogeneous structure structure, is at least the metallic compound magnetic phase composition more than two or two.

For example, R ₂TM ₁₄The compound barium in disperse ground, strontium ferrite material are tested the composite magnetic powder material in the M type permanent magnetic material, when the ferrite percentage by weight less than 60% the time, magnetic energy product is greater than 4MGOe.By at R ₂TM ₁₄Disperse distribution Ferrite Material in the M material, magnetic energy product can be regulated in the 4-12MGOe scope, with 1%-10%(wt%) binding agent mixing aftershaping, magnetic energy product can be regulated in the scope of 2-9MGOe.

By the resulting multi-phase compound permanent-magnet material of the present invention, its magnetic energy product all can obtain magnetic application separately between 2-15MGOe, the user can select the composite material permanent magnet of the suitable magnetic property trade mark from utilize the angle of permanent magnetic material most economically, obtains the rational ratio of performance to price.

Therefore, the present invention is the user of magnetic application, utilizes permanent magnetic material economically, and carrying out the magnetic Application Design provides maximum convenience.

Example 1:

Adopt Nd ₁₂Fe ₇₄B ₆Co ₈Alloy, its powder property is: (BH) m=11.0 MGOe Br=8.1KGs

Hcb＝5.5KOe Hcj＝8.4 KOe

Adopt BaO-6Fe ₂O ₃Alloy, powder property are (BH) m=2.5 MGOe Br=4.2 KGs

Hcb＝1.6 KOe Hcj＝2.1 KOe

Experiment value

BaO-6Fe ₂O ₃(wt%)

Magnetic property 0 10 20 30 40 50 60 70 80 90 100

Br KGs 8.1 7.3 6.6 6.1 5.7 5.2 4.8 4.6 4.3 4.2 4.2

Hcb KOe 5.5 4.6 4.1 3.7 3.1 2.8 2.3 2.2 1.8 1.5 1.6

Hcj KOe 8.4 7.5 6.9 6.2 5.6 4.7 3.8 3.5 3.0 2.2 2.1

(BH)m MGO 11.0 9.2 8.1 7.3 6.2 5.3 4.3 3.1 2.8 2.5 2.5

With the addition rule of the compound law of composite material, the calculated value of making is as follows:

BaO-6Fe ₂O ₃(wt%)

Magnetic property 0 10 20 30 40 50 60 70 80 90 100

Br KGs 8.1 7.5 6.9 6.8 6.1 5.7 5.3 5.0 4.7 4.3 4.2

Hcb KOe 5.5 4.9 4.3 3.9 3.5 3.1 2.7 2.5 2.1 1.8 1.6

Hcj KOe 8.4 7.5 6.5 5.9 5.2 4.6 3.9 3.5 2.9 2.5 2.1

(BH)m MGO 11.0 9.7 8.5 7.7 6.7 5.9 4.9 4.3 3.7 2.9 2.5

The relation curve of experiment value and calculated value is seen accompanying drawing.Tg θ _Meter-tg θ _Real=0.72

Claims (4)

1, multi-phase compound permanent-magnet material is characterized in that containing two or more magnetic phase component, and it is ferrite permanent-magnet materials that a component wherein must be arranged, and can be expressed as:

A=aX+bY+ $\underset{i}{\overset{}{\mathrm{\Σ}}}$ c _iZ _i(i=1,2……n)

Wherein, X mainly is barium, strontium permanent-magnet ferrite, and the weight percentage ranges in A is 0-70, and Y is a binder material, and the weight percentage ranges that accounts for alloy is 0-20; A, b are respectively X, the Y volume fraction in A; Z _iBe rare earth permanent-magnetic material, c _iBe Z _iAccount for volume fraction in the A alloy; A is a kind of novel composite permanent-magnetic material, has heterogeneous structure, by X, Y, Z _iBy a certain percentage, adopt the whole district or constituency sintering, the method for the whole district or constituency bonding is composited.

2, according to claims 1 said multi-phase compound permanent-magnet material, it is characterized in that Z _iBe respectively RxTMy type alloy, the Rx-TMy-Mz alloy constitutes heterogeneous composite material by it.

3, according to claim 1 or 2 said multi-phase compound permanent-magnet materials, it is characterized in that R is rare earth element Pr, Nd, Sm, Dy, TM is Fe, Co, Zr, Ti, Cr, Nb, V, M is Si, the Al of B, C, N and trace.

4, according to claim 2 said multi-phase compound permanent-magnet materials, it is characterized in that:

Among the RxTMy, the ratio of x and y is 1: 5 or 2: 17(at%); Among the RxTMyMz, x accounts for the 3-15(at% of whole alloy), y accounts for the 65-80(at% of whole alloy), z accounts for the 3-25(at% of whole alloy).

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