CN1052568A

CN1052568A - Produce method of permanent magnet and products thereof

Info

Publication number: CN1052568A
Application number: CN91100463A
Authority: CN
Inventors: 佐川真人; 山本日登志; 藤村节夫; 松浦裕
Original assignee: Sumitomo Special Metals Co Ltd
Current assignee: Proterial Ltd
Priority date: 1985-02-27
Filing date: 1985-04-01
Publication date: 1991-06-26
Also published as: CN1012235B; CN1176470A; CN1175066A; CN85101455A

Abstract

Produce method of permanent magnet and products thereof, comprise a kind of alloy powder is carried out forming processes, carry out sintering again, heat-treat afterwards.The magnetic energy product of product can reach 35MGOe, 40MGOe or higher.

Description

Produce method of permanent magnet and products thereof

What the present invention talked is rare earth-iron base permanent magnet or permanent magnetic material, in its composition at all with or only with cost an arm and a leg on a small quantity, the cobalt of resource scarcity, and the method for producing this product.

Permanent magnetic material is one of crucial electric, electronic material, is widely used in the ancillary equipment of various civil electric appliances, large-scale computer.Along with at present electric, electronic device being reduced the requirement that volume is raised the efficiency, correspondingly wish to improve the efficient of permanent magnetic material day by day.

The typical permanent magnetic material of Shi Yonging was alnico alloy, hard ferrite and rare earth-cobalt magnet in recent years.Recently because raw material cobalt supply instability has caused the minimizing to alnico magnet (comprising 20～30% cobalt by weight) demand.Replace, cheap slightly hard ferrite becomes main magnetic material now, on the other hand, so since in rare earth-cobalt magnet by weight the cobalt amount that contains very expensive up to 50～65%, in addition, the content of samarium in Rare Earth Mine (Sm) is also abundant.But because this magnet is more a lot of by force than the magnetic of other magnets, so be mainly used in the higher small-sized magnetic circuit of price, for price, the expansion scope of application and the consumption that reduces rare earth magnet, require magnetic material to break away from expensive cobalt or only use little cobalt, used main rare earth composition is the light rare earth element that is rich in the Rare Earth Mine, and the someone attempts to obtain this permanent magnet.For example, A.E.clark finds, sputter amorphous TbFe2, energy product is 29.5 mega gaussorersteds (MGOe) when 4.2 ° of K, after 300～500 ℃ of heat treatment, coercive force iHc is 3.4 kilo-oersteds (KOe) under the room temperature, and maximum magnetic energy product (BH) mox is 7MGOe.SmFe2 has also been carried out similar research, and report shows that energy product can be up to 9.2MGOe when 77 ° of K.But these materials all are the films made from sputtering method, can not do the magnet of what practicality.It was further reported that by the PrFe base alloy thin band of fast melt-quenching preparation, its coercive force iHc is 2.8KOe.In addition, Ku En discoveries such as (KOOn) is by (FeB) of fast melt-quenching preparation _0.9Tb _0.05La _0.95Coercive force iHc is up to 9KOe after 627 ℃ of tempering for amorphous thin ribbon, and residual magnetic flux density Br is 5KG.Yet, because its demagnetization curve is not the article of gratifying rectangular loop (referring to Applied Physics wall bulletin 39(10 in 1981) N.C.KOOn etc., P840～842), so the maximum magnetic flux of this strip is long-pending very low.L.Ka-bacoff etc. report, by the fast melt-quenching of (FeB) 1-xPrx composition (is X=0-0.3 by atomic ratio), can obtain the FePr binary system strip that coercive force under the room temperature can reach the KOe level., these fast melt-quenching strips or sputtered film are not that the permanent magnet (object) of any practicality also can not be made the permanent magnet of any practicality.From traditional based on FeBR the fast melt-quenching strip and can not obtain the shape bulk permanent magnet desirable based on the sputtered film of RFe with size.Because its magnetization curve is not gratifying rectangular loop, the FeBR that is reported so far base strip can not be made the permanent magnet of any practicality that can compare with magnet commonly used.Because sputtered film and fast melt-quenching strip itself are the materials of magnetic isotropy, so may obtain having the magnetically anisotropic substance of high standard Practical Performance in fact hardly.

Usually " R " represents rare earth element, and it comprises Y.

An object of the present invention is to propose a kind of novelty of producing permanent magnet or permanent magnetic material and practical method, wherein need not any expensive material, the method has been eliminated the shortcoming of former technology.

Another object of the present invention is to propose a kind ofly good magnetic, novelty to be arranged and the method for the production permanent magnet of practicality under room temperature and higher temperature, it can make the volume of the practicality of any desired shapes, its magnetization curve is the loop line of height rectangle, this method can effectively utilize the more light rare earth element of resource, and do not use the rare earth element of resource scarcity basically, such as Sm.

The 3rd purpose of the present invention is to propose a kind of new method of making permanent magnet or permanent magnetic material, and it only still has good magnetic with little cobalt.

The 4th purpose of the present invention is to improve the temperature dependency of Fe-B-R base magnetic material and magnet.(that is, reducing)

The 5th purpose of the present invention is to propose some kinds of permanent magnetic materials and permanent magnet, and their performances are well to the degree of having never heard of in the past.Also proposed to produce their method.

Other purpose is not put in the text from broken.

Fully study through the present inventor and to have reached above-mentioned purpose, and found, after oversintering, in a certain composition scope, the magnetic of Fe-B-R alloy, be expressed as the rectangular loop of coercive force and demagnetization curve with specific term, (compacting) is a kind of to have the powder of specific granule size greatly to be improved by making, carry out sintering for the object after being shaped, heat-treat subsequently or No. the 126802nd, the European patent application EP A of No.-90801, (Japanese patent application 58(1983) and corresponding present announcement under some specific conditions), carry out so-called burin-in process.

But detailed again discovers, when above-mentioned heat treatment, adopts more specifically condition, carries out the heat treatment of two classes, its coercive force, and the rectangular loop of demagnetization curve can obtain further improvement, and therefore, the change of magnetic has reduced.

More clearly say,, the invention provides a kind of method of production hydromagnetic material, it is characterized in that comprising the following steps: according to first viewpoint

Make a kind of mean particle size and be 0.3 to 80 micron alloy powder, the percentage of atom is in its composition, 8～30% R(supposition R is one of rare earth element that comprises Y at least), 2～28%, B, all the other are iron and more inevitable impurity (promptly hereinafter said " FeBR base alloy "), shaped-article is burnt till shape under 900～1200 ℃ of temperature, under 750～1000 ℃ of temperature, carry out heat treatment first then, cool off with 3～2000 ℃/minute the cooldown rate object after to the heat treatment first time again, at last under 480～700 ℃ of temperature to carrying out the heat treatment second time through above-mentioned cooled object.

As there is not the percentage that the hereinafter said percentage of Special Statement all refers to atom.

According to second viewpoint of the present invention, the cobalt amount that contains of FeBR base alloy is not more than 50%, and some is substituted the iron in the FeBR base alloy, in view of the above, has increased in the Curie point of the magnetic material of consequently making aspect the improvement of temperature property.

According to the 3rd viewpoint of the present invention, comprise at least a among the additional elements M in the FeBR base alloy, its percentage is no more than set-point (except 0%);

Be not more than 9.5% V, be not more than 12.5% Nb,

Be not more than 10.5% Ta, be not more than 9.5% Mo,

Be not more than 9.5% W, be not more than 8.5% Cr,

Be not more than 9.5% Al, be not more than 4.5% Ti,

Be not more than 5.5% Zr, be not more than 5.5% Hf,

Be not more than 8.0% Mn, be not more than 8.0% Ni,

Be not more than 7.0% Ge, be not more than 3.5% Sn,

Be not more than 5.0% Bi, be not more than 2.5% Sb,

Be not more than 5.0% Si, and the Zn that is not more than 2.0%.

If comprise two or more M, its summation is not more than given largest percentage among the contained various additional elements M so.

The adding of most additional elements M all is in order to improve its coercive force.

According to the 4th viewpoint of the present invention, it is particular value that FeBR base alloy contains the cobalt amount, (as described in second viewpoint), and the additional elements M(that also can contain specified quantitative is as described in the 3rd viewpoint).

By following detailed argumentation also with reference to the accompanying drawings, can clearly understand above-mentioned purpose of the present invention, other purpose and feature, this accompanying drawing is used for graphic extension separately.Wherein:

Fig. 1 is illustrated in the content of Co in the FeCoBR base alloy and the relation between the Curie point.

To further explain details of the present invention below.

First viewpoint: (as no Special Statement, the argumentation of first viewpoint generally also is used for the back viewpoint).

In permanent magnetic material of the present invention, the content of B should not be less than 2%(% wherein and represent atomic percent in the alloy hereinafter), with adapt to the coercive force iHC value that is no less than 3KOe and also again can not be more than 28% so that residual magnetic flux density Br is not less than about 6KG(kilogauss), this value is much better than hard iron, and the content of R should be no less than 8% so that its coercive force is not less than 3KOe.But, need allow the content of R not be higher than 30%, because R burns too easily, the difficulty that this just causes technical finesse and produces also makes its cost improve.

Raw material are cheap, thus the present invention seem of great use because usefulness be rare earth element that resource arranged such as ₂And need not use Sm, not Sm as main component.

The rare-earth element R that the present invention adopts comprises Y, also comprises and light, heavy rare earth element may change a word at least with a kind of that R comprises Nd, Pr, La, Ce, Tb, Dy, Ho, Er, Eu, Sm, Gd, Pm, Tm, Yb, Lu and Y.Use some light rare earth element just passable, as also obtaining some properties with Nd and Pr as R.Usually, with in Nd, Pr, Dy, Tb, Ho or the analogous element a kind of as R just, but in fact for the convenient mixture (mischmetal, praseodymium neodymium mixture) that uses two or more element etc.Can adopt the mixture of Sm, Y, La, Ce, Gd etc. and other R element, particularly with mixtures such as Nd, Pr, Dy, Tb, Ho.Should be noted that R may not be the pure rare earth element, may contain impurity, other rare earth element, Ca, the Mg, Fe, Ti, C, the O etc. that carry secretly inevitably in process of production into need only industrial feasible.In order to obtain best effects, improve coercive force, R is divided into R ₁And R ₂, R ₁Be one or more elements in the colony of Dy, Tb, Gd, Ho, Er, Tm and Yb composition, R ₂In contain 80% Nd and Pr at least, remaining is to remove R ₁Outside one or more rare earth elements (comprising Y), it is few more good more preferably not comprise Sm or content, La does not answer content too many yet, is preferably lower than 2%(and is lower than 1% better).

Used boron can be pure boron or iron boron, can comprise impurity such as resembling Al, Si, C.In magnetic material of the present invention,, but may comprise the impurity of unavoidably carrying secretly into because of production process except B and R surplus are Fe.

The designed permanent magnetic material of the present invention contains the R element of 8-30%, the boron element of 2-28%, and all the other are iron, its magnetic is represented with maximum magnetic energy product (BH) max, substantially exceeds the 4MGOe that hard ferrite shows.

With regard to R, preferably allow Nd and Pr sum in whole R, account for 50%(at least and preferably reach 80% or higher) so that it has bigger magnetic and reliable, cheap.

The scope of a composition of very good selection, wherein light rare earth element (Nd, Pr) account for whole R 50% or more, it is made up of 12～24% R, 3～27% B and remaining Fe, maximum magnetic energy product (BH) max played 10MGOe.Fabulous situation is to get such composition range, wherein Nd and Pr sum account for whole R 50% or more, and it is made up of 12～20% R, 5～24% B and balance iron, and maximum magnetic energy product (BH) max that shows of the magnetic of finished product surpasses 15MGOs so, can reach 35MGOe.If R ₁Account for 0.05～5%, R accounts for 12.5～20%, B account for 5～20% all the other be iron, maximum magnetic energy product (BH) max just keeps can not being lower than 20MGOe so, coercive force iHc is not less than 10KOe simultaneously.But the ageing method of the present invention's design brings an other effect, in addition, if contain 0.2～3% R in the composition ₁, 13～19% R, 5～11% B, all the other are iron, maximum magnetic energy product (BH) max is brought up to be not less than 30MGOe.

More better FeBR proportion of composing is 12.5～20% R, 5～15% B, and 65～82.5% iron, available at that time magnetic energy product is 20 or higher.R surpass 20% or Fe be lower than at 65% o'clock, remanent magnetism Br will reduce.Surpass at 82.5% o'clock at Fe content, coercive force iHc will reduce.

Further more improved FeBR proportion of composing then contains R13～18%, contains B5～15%, iron content 67～82%, and at this moment magnetic energy product can surpass 20MGOe, can reach 30MGOe at 5～11% o'clock and contain B.

Surprising is that magnetic energy product can reach 40MGOe even 44MGOe, such as the B that contains approximate 6～7%, and 13～14.5% R, all the other are Fe(or contain a certain amount of CO and/or M).Co content can reach 10%, and M content can reach about 1%.

In among a small circle, magnetic energy product can reach 35MGOe or bigger, that is, boracic 6～11% contains R13～16%, and all the other are Fe.M content can reach 2% and Co content can reach 15%.

Should be noted that to comprise Co and M in follow-up viewpoint, their content should be included in the content of Fe discussed above, because Fe is defined as surplus in every kind of mixture.

Permanent magnetic material of the present invention can be by grinding, shaping (compacting), sintering, and the alloy of being made up of mentioned component is carried out further heat treatment make.

Concrete equipment used in the method below in conjunction with the FeBR permanent magnetic material that has magnetic anisotropy in production is made explanations to the present invention.

As used raw material, can be by electrolytic iron as ferrous components, pure boron or iron boron are formed as B composition, 95% rare earth R or purer R.In above-mentioned scope, these materials weigh up weight in advance, mix by certain prescription, are smelted into alloy, and for example, in vacuum or having under the inert gas atmosphere condition by the high frequency melting, methods such as electric arc melting melt, and cool off subsequently.The alloy that obtains is like this roughly ground with bruisher, kibbling mill etc.Carry out fine grinding with jet pulverizer, ball mill etc. more subsequently.Fine grinding can be carried out the dry state grinding under inert gas atmosphere, also can carry out hygrometric state and grind under organic solvent (such as acetone, toluene etc.) condition, and can make the mean particle size of alloy powder by fine grinding is 0.3～80 micron.When mean particle size is lower than 0.3 micron, considerable oxidation can take place in fine grinding or production stage afterwards, the result causes density increase, magnetic to descend.(it is possible further reducing granular size under specific condition, still, does like that and has any problem and preparation process and cost of equipment are considerable.) if mean particle size surpasses 80 microns and just can not obtain stronger magnetic, with term be coercive force also at the worst.Obtain ferromagnetism, the mean particle size of alloy smalls with 1～40 micron for well, be preferably 2～20 microns.

The alloy powder that with granular size is 0.3～80 micron carries out press molding in a magnetic field (for example, being not less than the magnetic field of 5KOe).Forming pressure is preferably 0.5～3.0 ton/centimetre ²(ton/cm ²).For press molding in magnetic field, above-mentioned alloy powder can be shaped in special equipment, also can be shaped in certain organic solvent (such as acetone, toluene etc.).Object after the shaping will carry out sintering under 900～1200 ℃ of temperature, sintering will continue the regular hour in reduction or non-oxide atmosphere, such as, be not higher than 10 ^-2In the vacuum of torr or at inert gas, carry out in the reducing gas atmosphere, its purity of air pressure that preferably allows inert gas be in 1～760 torr is 99.9% or higher.If sintering temperature below 900 ℃, then can not get enough sintered densities, also can not get higher residual magnetic flux density.If temperature is higher than 1200 ℃, the size of distortion of sinter cognition and crystalline particle is just out of hand, and the loop rectangularity of the remanent magnetism of product, magnetization curve back will variation like this.On the other hand, desirable 5 minutes of the time of sintering or long again, but oversize cause problems one by one just for a large amount of productions.Preferably to get 0.5～4 hour be a sintering period so obtain needed magnetic, or the like, bear in mind.Be noted that very good allowing keeps a high level as the inert gas of sintering atmosphere, reducing gas, oxidized because the R composition at high temperature is easy to.When using inert gas, under the reduced pressure between 1 to 760 torr, sintering can be affected to obtain higher sintered density.

Yet during the sintering, the speed that temperature raises does not have any particular restriction, if be shaped as above-mentioned hygrometric state, can adopt the temperature rate of rise of 40 ℃/min is desirable to remove organic solvent.If it is keep 0.5 hour or longer heating process 200 to 800 ℃ of temperature ranges, also fine in order to remove organic solvent.When cooling off behind the sintering, preferably adopt the cooling rate that is not less than 20 ℃/min to limit the variation (qualitatively) of energy product.For by the heat treatment carried out subsequently or burin-in process to strengthen magnetic, the cooldown rate behind the sintering preferably is not less than 100 ℃/min.(still, it should be noted that heat treatment can follow finishing of sintering closely and carries out).

Step of heat treatment is as follows after the sintering.At first, the object that is sintered will carry out the heat treatment of phase I under 750～1000 ℃ of temperature, and the cooldown rate with 3～2000 ℃/min is cooled to be no more than 680 ℃ to it then.Then, in 480～700 ℃ of temperature ranges, chilled object is carried out the heat treatment second time.

About heat treated temperature of phase I, if be lower than 750 ℃ then heat treated effect of phase I is so poor so that coercitive recruitment is very little.If temperature surpasses 1000 ℃, the crystalline particle that is sintered object just increases, thereby coercive force descends.

In order to increase coercive force, improve the rectangularity of magnetization curve back loop line, reduce and change, the phase I, heat treated temperature was preferably got 770～950 ℃, get 790～920 ℃ then better.

With regard to the cooldown rate that adopts (then phase I heat treatment), if cooldown rate is lower than 3 ℃/min, so coercive force just descend and also the rectangularity of magnetization curve back loop line with regard to variation, yet cooldown rate is greater than 2000 ℃/min, just produced fine fisssure in the burning object, coercive force also descends like this.To keep certain cooldown rate in the phase I heat treatment temperature to being not more than between 680 ℃ the temperature.Be not higher than in 680 ℃ of temperature ranges, cooling can slowly also can be fast.If the lower limit of chilling temperature scope is higher than 680 ℃ under given cooldown rate, that coercive force will obviously descend.For the variation that deperms, do not cause performance to reduce, to give regularly in cooldown rate, it is desirable that the lower limit of chilling temperature is not higher than 650 ℃.In order to increase the rectangularity of coercive force, improvement magnetization curve back loop line, be change equally in order to deperm, suppress the generation of fine fisssure, very good cooldown rate is 10～1500 ℃/min, is preferably 20～1000 ℃/min.

Characteristics of two phase heat treatment of the present invention's design are, after the first heat treatment under 750～1000 ℃ of conditions, be cooled to not be higher than 680 ℃ the temperature that is adopted, thus, can between 750 ℃ and 700 ℃, cool off fast, then, in 480～700 ℃ low temperature range, carry out the heat treatment second time.But it should be noted that if just carry out the heat treatment second time immediately afterwards in first heat treatment and cooling (such as in stove, cooling off etc.).The improvement of product magnetic just is restricted so, in other words, this means crystalline texture or metallographic range of instability that a unknown is arranged between 750 ℃ and 700 ℃, and it causes the degeneration of magnetic; , cooling can be eliminated this influence fast.Should understand, the heat treatment first time and carry out subsequently give after the fixed cooling heat treatment for the second time and can carry out immediately, perhaps carry out a moment after a while.

Heat treated temperature limitation is between 480～700 ℃ for the second time.If temperature is lower than 480 ℃ or be higher than 700 ℃, then the improvement of the rectangularity of coercive force and magnetization curve back loop line just reduces.In order to increase coercive force, to improve the rectangularity of magnetization curve back loop line, also variation in order to deperm, very good the taking of heat treated temperature is preferably between 550～650 ℃ between 520～670 ℃ for the second time.

Owing to have any problem in extremely short time inner control temperature, the cycle of adding, oversize industrial index descended, so the phase I heat treatment period is not made particular restriction, time range is 0.5～8.0 hour preferably.

Owing to utmost point short time inner control temperature difficulty, the cycle, oversize industrial index descended as mentioned above, so also the second stage heat treatment period is not made particular restriction, time range is 0.5～12.0 hour preferably.

The reference data that when providing burin-in process below atmosphere is required.Because the R composition in the alloy mixture, at high temperature can with oxygen or moisture generation kickback, aspect vacuum degree, should not be higher than 10 ^-3Torr.Also can be with inert gas or reducing gas atmosphere, its purity should be 99.99% or higher.In above-mentioned scope, selected sintering temperature is by the composition decision of permanent magnetic material, and aging temperature can never be higher than in the selected sintering range to be chosen.

Should be pointed out that burin-in process, comprise first, second time heat treatment, can after sintering, carry out, also can heating again behind cool to room temperature.No matter the magnetic which method obtains is all identical.

The not specific magnetic anisotropy permanent magnet that is limited to of the present invention, roughly the same method also is applicable to the magnetic isotropy permanent magnet, if extruding the time does not have magnetic field exist in forming process, can obtain outstanding magnetic.

If composition is 10～25% R, 3～23% B, surplus is Fe and more inevitable impurity, then isotropic magnet shows Maximum Energy Product (BH) max that is not less than 3MGOe.Though the magnetic of isotropic magnet is 1/4～1/6 of anisotropy magnet magnetic,, the magnet of making by method of the present invention is stronger than the magnetic of general isotropic magnet.When R content increased, iHC just increased, but Br has just reduced after arriving maximum.Like this, when the content of R not should less than 10% also not more than 25% so that (BH) max be not less than 3MGOe.

When the content of B increased, iHC increased, but Br has just reduced after reaching maximum.Like this content of B should be between 3% to 23% so that (BH) max be not less than 3MGOe.

Very goodly can obtain ferromagnetism, represent to be not less than 4MGOe with (BH) max, the Main Ingredients and Appearance of R is a light rare earth element in this mixture, accounts for 50% or some more again such as Nd and Pr(in whole R), it is made up of 12～20% R element, 5～18% B element and surplus Fe.It would be desirable such mixture, R Main Ingredients and Appearance wherein is that light rare earth element is such as Nd, Pr etc., and this mixture is by 12～16% R, 6～18% B and surplus Fe form, because the magnetic that the finished product isotropic magnet is shown is represented by (BH) max, be not less than 7MGOe, this is worth in the technology of former production isotropic magnet never must be.

As for anisotropy magnet, generally need not any adhesive and lubricant, because they have obstruction to orientation in being shaped.But for isotropic magnet, add adhesive, lubricant etc. pressure processing efficient is improved, increase the intensity of finished product etc.

The permanent magnet of the present invention's design also allows to exist impurity, and this is inevitable in industrial production.Promptly in given range, can comprise Ca, Mg, O, C, P, S, Cu etc.As long as total impurities is no more than 4%, Ca, Mg and/or C should be more than 4% in the impurity, and Cu and/or P are no more than 3.5%, and S is no more than 2.5%, and O is no more than 2% and is fine.C may bring into from used organic bond, and Ca, Mg, S, P, Cu etc. may bring into from approach such as raw material, production processes.The influence of bringing into Br of C, P, S and Cu is actually similar to the situation of not carrying out burin-in process, mainly is that coercive force is worked because wear out.About this point, can be No. the 101552nd, present disclosed european patent application (EPA) with reference to our early stage european patent application, wherein fixed impurity content be decided by the Br level of requirement.

Therefore as mentioned above, first viewpoint of the present invention is pointed out cheap, and the Fe-based permanent magnetic material is not wherein used Co at all in the composition, and it shows higher remanent magnetism, and bigger coercive force and magnetic energy product have a higher-value industrial.

Above-mentioned FeBR base magnetic material and magnet, its main (be at least 50% of volume, better is 80%) magnetic is a kind of FeBR type tetragonal structure mutually, crystallization property is far different than fast melt-quenching strip or any magnet of obtaining thus.Its center chemical analysis is considered to R ₂Fe ₁₄B and lattice parameter a approximately is 8.8 dust c approximately is 12.2 dusts.The grain size of finished product magnetic material is preferably got 2～40 microns in the scope (FeCoBR, FeBRM or FeCoBRM magnetic material are 1～90 micron) of 1-80 micron usually.Can be about the structure of crystal with reference to No. the 101552nd, european patent application (EPA).

The FeBR base magnetic material comprises a kind of less important non-magnetic phase, and it is mainly by rich R(metal) phase composition and surround the crystal grain of main magnetic phase.This non-magnetic had both made amount seldom also 1% of effective ratio such as volume just can work completely very much mutually.

To 370 ℃ (being suitable for Tb), typical case is about 300 ℃ or higher (being suitable for Pr, Nd etc.) to the Curie point scope of FeBR base magnetic material from 160 ℃ (being suitable for Ce).

Second viewpoint

According to said second viewpoint of the present invention, the cobalt Co that the FeBR base magnetic material can also contain is a certain amount of (50% or be less than 50%), the Curie point of finished product FeCoBR magnetic material will improve like this.Promptly a part of Fe is replaced by Co in the FeBR base magnetic material.Heat treatment behind the sintering (wearing out) improves the rectangularity of coercive force and magnetization curve back loop line, and this fact is published in Japanese patent application the 58th～No. 90802, corresponding to No. the 126802nd, present european patent application (EPA).

By this viewpoint, as previously mentioned, can further improve its performance by carrying out the heat treatment second time.For FeCoBR magnetic material heat treatment method, be shaped and sintering method in fact when producing the FeBR base magnetic material used method identical.

In general, through identifying, the Curie point of some Fe alloy improves with the increase of adding Co content, however the Curie point of other Fe alloys descend with the increase of adding Co content, cause complicated result to be difficult to give material, as shown in Figure 1.By this viewpoint, have been found that the result who replaces as to the part Fe in the FeBR system, Curie point Tc improves gradually along with the increase of adding Co content.Also proved a similarly tendency, promptly in FeBR base alloy the type of R be the inessential Co(that adds trace such as, only add 0.1% to 1%) to improving Curie point Tc just effectively.By (77-x) FexCo8B15Nd among Fig. 1 as an example, the Curie point Tc that its explanation can make several alloys is between about 300 ℃ and about 670 ℃, and occurrence is decided on the content of Co.

By this viewpoint, in the FeCoBR base permanent magnet, B, R and (Fe+Co) content of each composition is identical with content in FeBR base magnet basically.

The content of cobalt Co should be no more than 50%, because its costliness, also considers improvement and the Br of Curie point Tc.In general, mix with 5% to 25% amount, it is best particularly to mix 5% to 15% effect.

By this viewpoint, if permanent magnetic material is by 8～30% R, 2～28% B, no more than 50% Co and in fact surplus all be that Fe forms, the magnetic of so this material is not less than 3KOe aspect coercive force, remanent magnetism Br is not less than 6KG, and maximum magnetic energy product (BH) max far surpasses the value of hard ferrite.

Optimal cases is a such composition scope, promptly wherein the Main Ingredients and Appearance of R be light rare earth element (Nd, Pr) account for whole R 50% or more some more, the R by 12～24%, the Co of 3～27%B no more than 50% and in fact surplus all be that Fe forms.Because the maximum magnetic energy product of finished product (BH) max meets or exceeds 10MGOe.

Better scheme is a such composition scope, promptly wherein whole R contains 50% or more more Nd+Pr, it is by 12～20% R, 5～24% B, no more than 25% Co and in fact surplus all be that iron is formed, can obtain stronger magnetic because do like this, represent to surpass 15MGOe with (BH) max and can reach 35MGOe or higher.When Co is no less than 5%, the temperature coefficient of Br (a) is not higher than 0.1%/℃, this means that temperature dependency is fine.Be not higher than under 25% the situation containing Co amount, Co has contribution and other magnetic is not caused harmful effect (if contain Co amount be not higher than 23% can obtain identical magnetic even improvement is arranged) improving Curie point Tc.If R by 0.05～5% ₁, 12.5～20% R, 5～20% B, no more than 35% Co and balance iron are formed, and can make maximum magnetic energy product (BH) max keep being not less than 20MGOe and iHc surpasses 10KOe.But, can carry out further burin-in process by the present invention for such component.In addition, as fruit component be 0.2～3% R ₁, 13～19% R, 5～11% B, no more than 23% Co and balance iron, its maximum magnetic energy product (BH) max surpasses 30MGOe.

All the FeBR system has broken away from CO, and the FeCOBR base magnet of being invented has not only improved temperature dependence owing to added CO, and owing to improved the rectangularity of magnetization curve back loop line, maximum magnetic energy product also can be improved thus.In addition, since Co is more corrosion-resistant than Fe, to make these magnets more corrosion-resistant be possible owing to added Co so.

Isotropism FeCOBR magnet

Have 50% or the Co of less than 50% replace Fe, this point almost is identical with the basic isotropic magnet of FeBR, and is particularly all the more so about the content of R and B.The maximum magnetic energy product of having mentioned (BH) max is that the component of 4MGOe can contain 35% cobalt or few again a little at least; And component optimal, that (BH) max surpasses 17MGOe at least can contain cobalt 23% or less than 23%.

The impurity content of FeCoBR magnetic material can be basic identical with the FeBR base magnetic material.

The 3rd viewpoint (FeBRM magnetic material)

The 4th viewpoint (FeCoBRM magnetic material)

According to the 3rd, the 4th viewpoint of the present invention, some additional element M can be mixed the said FeBR base magnetic material of first viewpoint or be mixed the said FeCoBR magnetic material of second viewpoint, and this has just constituted the 3rd, the 4th viewpoint respectively.

Additional elements M is made up of a kind of element of selecting from following element colony at least, these elements are: V, Nb, Ta, Mo, W, Cr, Al, Ti, Zr, Hf, Mn, Ni, Ge, Sn, Bi, Sb, Si and Zn, its given consumption was said in summarizing in front.In most cases, mixing M is in order to improve the rectangularity of coercive force and loop line, particularly all the more so to anisotropic magnetic material.

In fact about heat treatment, other preparation method, for example be shaped, methods such as sintering will can be used for the 3rd, the 4th viewpoint equally.

As for content and the effect of R and B, in fact with first viewpoint point out the same, also will be used for the 3rd, the 4th viewpoint.About Co, in fact as second viewpoint is said, will be used for the 4th viewpoint equally.

Now, according to the additional elements M of these viewpoints argumentations in permanent magnetic material, their adding purpose is to increase coercive force.Particularly increase coercive force, thereby improve the rectangularity of magnetization curve back in the maximum zone of Br.Coercitive increase can cause the increase of magnet stability and enlarge their purposes.But Br but reduces along with the increase of M content.For this reason, its maximum magnetic energy product (BH) max has just reduced.The alloy that contains M is very useful, and is more useful when particularly the scope of (BH) max is not less than 6MGOe, because need the purposes of high-coercive force more and more recently, would rather be cost to reduce (BH) max a little.

Add the influence that additional elements M causes Br in order to investigate thoroughly, the M that adds varying number measures the variation of Br then.In order to make Br considerably beyond this value of the about 4KG of hard iron, also in order to make (BH) max this value of about 4MGOe considerably beyond hard iron, the upper limit that adds the M amount is determined as follows:

9.5%V，12.5%Nb，10.5%Ta，

9.5%Mo，9.5%W，8.5%Cr，

9.5%Al，4.5%Ti，5.5%Zr，

5.5%Hf，8.0%Mn，8.0%Ni，

7.0%Ge，3.5%Sn，5.0%Bi，

2.5%Sb，3.5%Si，2.0%Zn。

The addition of M is non-vanishing, can use a kind of, the M element of two or more.When containing two or more M element, the character of product represents that according to the median between the characteristic value of each element of add each constituent content should be in above-mentioned percentage ranges usually, and M element total content should be greater than the actual given maximum of each element.

By above-mentioned FeBRM component, its maximum magnetic energy product of permanent magnetic material (BH) max of the present invention's design is considerably beyond the value (reaching 4MGOe) of hard ferrite.

Preferably adopt following composition scope, promptly wherein overall R comprise 50% or more more light rare earth element (Nd, Pr), it is by 12～24% R, 3～27% B, one or more additional elements-be no more than 8.0% V are no more than 10.5% Nb, be no more than 9.5% Ta, be no more than 7.5% Mo

Be no more than 7.5% W, be no more than 6.5% Cr, be no more than 7.5% Al, be no more than 4.0% Ti, be no more than 4.5% Zr, be no more than 4.5% Hf, be no more than 6.0% Mn, be no more than 3.5% Ni, be no more than 5.5% Ge, be no more than 2.5% Sn, be no more than 4.0% Bi, be no more than 1.5% Sb, be no more than 4.5% Si and be no more than 1.5% Zn-just passable as long as its total amount is no more than the maximum of atomic percent actual given among the additional elements M, surplus be actually Fe ideally (BH) max can surpass 10MGOe.Better situation is such compositing range, and wherein whole R comprises 50% or more light rare earth element (Nd, Pr), and it is by 12～20% R, 5～24% B, and one or more additional elements M-is no more than 6.5% V, is no more than 8.5% Nb,

Be no more than 8.5% Ta, be no more than 5.5% Mo, be no more than 5.5% W,

Be no more than 4.5% Cr, be no more than 5.5% Al, be no more than 3.5% Ti,

Be no more than 3.5% Zr, be no more than 3.5% Hf, be no more than 4.0% Mn,

Be no more than 2.0% Ni, be no more than 4.0% Ge, be no more than 1.0% Sn,

Be no more than 3.0% Bi, be no more than 0.5% Sb, be no more than 4.0% Si and be no more than 1.0% Zn-as long as its total amount is no more than the maximum of atomic percent actual given among the additional elements M, surplus is actually Fe, obtains to be not less than (BH) max value of 15MGOe and all is possible up to 35MGOc even higher (BH) max value.

If composition is 0.05% R ₁, 12.5～20% R, 5～20% B, all the other are Fe to be no more than 35% Co, can keep maximum magnetic energy product to be not less than 20MGOe so and iHc surpasses 10KOe.But, can carry out further heat treatment according to the present invention for a kind of like this mixture.In addition, if composition is 0.2～3% R ₁, 13～19% R, 5～11% B and all the other are Fe, its maximum magnetic energy product surpasses 30MGOe.Useful especially M is V, Nb, Ta, Mo, W, Cr and Al.By its effect the content of M preferably be not less than 0.1% and not surpass the optimal situation of 3%(be 1%).

Can to Br what kind of influence be arranged so that understand the content of M referring to No. the 101552nd, former european patent application (EPA) about the effect that adds additional elements M.So just can determine the content of M and the relation between the various Br level of wanting to obtain.

Isotropic magnet

About isotropic magnet, except following situation, in fact the said viewpoint in front is available equally.The content of additional elements M should be identical with anisotropic magnetic material (the said magnetic material of the 3rd, the 4th viewpoint).Just require to satisfy following requirement:

Be no more than 10.5% V, be no more than 8.8% W,

Be no more than 4.7% Ti, be no more than 4.7% Ni,

And the Ge that is no more than 6.0%.

The isotropic magnet of saying as for from first to the 4th viewpoint, in general, containing a certain amount of impurity allows, such as, C, Ca, Mg(must not surpass 4% for every kind), P(is no more than 3%), S(is no more than 2.5%), Cu(is no more than 3.3%), or the like, only require that its summation is no more than each given maximum.

In the literal below, will make an explanation by some examples according to the embodiment and the effect of the present invention of each viewpoint.But, can see that the present invention is not subjected to the restriction of the method for given example and description thereof.

Subordinate list 1-20 express prepare the FeBR base permanent magnet through the following steps characteristic particularly, table 1～5, table 6 is to 10, table 11 to 15 and table 16 enumerated respectively with FeBR to 20, FeCoBR, FeBRM and FeCoBRM are every characteristic of the permanent magnet of base.

(1) about raw material, purity is 99.9%(percentage by weight, hereinafter the material purity of Shi Yonging with) electrolytic iron as Fe, ferroboron (the Al that contains 19.38% boron 5.32%, 0.74% Si, 0.03% C and surplus Fe) as B, purity be 99% or more highly purified rare earth element (impurity mainly is that other rare earth metal is as R.

Purity is that 99.9% electrolytic cobalt is as Co.

Used M element is Ta, Ti, Bi, Mn, Sb, Ni, Sn, Zn and Ge, and every kind of purity is 99%, and purity is 98% W in addition, and purity is 99.9% Al, and purity is 95% Hf.With the ferrozirconium that contains Zr77.5%, contain V81.2% the alum ferroalloy, contain the ferroniobium of Nb67.6%, the ferrochrome that contains Cr61.9% is respectively as Zr, V, Nb and Cr.

(2) method by high-frequency induction melts raw material.An aluminum crucible is used as crucible and casts to obtain blank in a water-cooled copper mold.

(3) blank that obtains after the fusing is crushed to-35mesh, on ball mill, grinds to obtain the state of given mean particle size.

(4) in magnetic field, powder is carried out press forming with setting pressure.But, in the production of isotropic magnet, do not add any magnetic field during shaping.

(5) object after the shaping carries out sintering in 900 ℃～1200 ℃ specific temperature ranges in given atmosphere, carries out specific heat treatment afterwards again.

Example 1

Smelt by in argon gas, carrying out high frequency that to obtain composition be a kind of alloy of 77Fe9B14Nd by atomic percent, cast with water-cooled copper mold.Resulting alloy is slightly ground with bruisher, become the particle that is not more than 40mesh, carry out fine grinding with ball mill then in argon gas, reaching mean particle size is 8 microns.To through handling the powder that obtains like this, in the magnetic field of 10koe, use 2.2ton/Cm again ²Exert pressure, shaping, in purity is the argon gas of 99.99%, 760 torrs, carry out sintering then, sintering temperature is 1120 ℃ and continues 2 hours.After sintering, make object that sintering crosses cooldown rate cool to room temperature with 500 ℃/min.Thereafter, carry out burin-in process under 820 ℃ of conditions in argon gas atmosphere, ageing time has nothing in common with each other, then make it to be cooled to not be higher than 650 ℃ temperature, further again burin-in process, 600 ℃ of aging temperatures with 250 ℃/min of cooldown rate, continue 2 hours, to obtain the magnet of the present invention's design.

The character of gained magnet is listed in table 1, has also listed the character of carrying out the reference examples of single phase heat treatment under 820 ℃ of conditions in the table.

Table 1

Example 2

By obtaining in argon gas arc process fusing in the composition by atomic percent is a kind of alloy of 70Fe13B9Nd8Pr, casts with a water-cooled Copper casting mould.Alloy to gained slightly grinds with bruisher, makes its granular size be not more than 40mesh, carries out fine grinding with ball mill in certain organic solvent again, and reaching mean particle size is 3 microns.The powder that obtains by this method is again in the magnetic field of 15Koe, with 1.5ton/Cm ²Pressure pressurize, be shaped, then in purity is the argon gas of 99.99%, 250 torrs, carry out sintering, sintering temperature is 1140 ℃ and continues 2 hours, after sintering, makes through the object of the oversintering cooldown rate cool to room temperature with 150 ℃/min.Subsequently, carry out 2 hours phase I heat treatment, heat treatment temperature has nothing in common with each other, as shown in table 2, cooldown rate with 300 ℃/min makes it to be cooled to not be higher than 600 ℃ again, carries out 8 hours second stage heat treatment then under 640 ℃ of conditions, to obtain the magnet of the present invention's design, the character of the magnet that is generated is in table 2, also lists the character of reference examples (after the single phase burin-in process) in the table.

Table 2

Example 3

Obtain its atomic percent Fe-B-R alloy as shown in table 3 by fusing in argon gas electric arc, cast with a water-cooled Copper casting mould.This alloy is roughly ground in bruisher, made its granular size be not more than 50mesh, carry out fine grinding with ball mill in certain organic solvent again, making its mean particle size is 5 microns.In the magnetic field of 12KOe with 2.0ton/cm ²Pressure these powder are carried out press molding, be to carry out sintering under 99.999%, the 150 torr air pressure then in purity, sintering temperature is 1080 ℃, continues 2 hours, makes it to be cooled fast to the cooldown rate of 600 ℃/min subsequently to reach room temperature.Thereafter, in the argon gas of high-purity 500 torrs, carry out 2 hours burin-in process, aging temperature is 800 ℃, then the cooldown rate with 300 ℃/min makes it to be cooled to not be higher than 630 ℃, under 620 ℃ of conditions, carry out 4 hours second stage burin-in process again, to obtain the alloy magnet of the present invention's design.The magnetic of finished product magnet is listed in table 3, and table 3 has also been listed the character of reference examples (after the phase I burin-in process).

Table 3

(composition)	Remanent magnetism (KG)	Coercive force (KOe)	Maximum magnetic energy product (MGOe)
				78Fe9B13Nd	11.4	14.3	27.1
69Fe15B14Pr2Nd	8.5	12.4	15.8
				71Fe14B1Nd5Gd	8.9	10.9	17.3
66Fe19B8Nd7Tb	8.1	12.4	15.2
				69Fe14B10Nd5Gd (after the phase I is aging)	8.5	6.9	14.2
66Fe19B8Nd7Tb (after the phase I is aging)	7.9	7.4	11.9

Example 4

Obtain casting with a water-cooled copper mold by fusing in argon gas electric arc by the Fe-B-R alloy of atomic percent for following routine composition.These alloys are slightly ground with bruisher make its granular size be not more than 35mesh, carry out fine grinding with ball mill in certain organic solvent again, reaching mean particle size is 4 microns.To resulting powder, under no magnetic field condition with 1.5ton/cm ²Pressure carry out press molding, be to carry out sintering under 99.99%, the 180 torr air pressure in purity subsequently, sintering temperature is 1090 ℃, continues 2 hours, then the cooldown rate with 400 ℃/min is quickly cooled to room temperature.Thereafter, in high-purity, carry out the phase I burin-in process in the argon gas of 650 torr air pressure, the temperature of burin-in process is 840 ℃, continue 3 hours, next the cooldown rate with 180 ℃/min makes it to be cooled to not be higher than 600 ℃, carries out the second stage burin-in process at 630 ℃ * 2 hours under the condition then, to obtain the magnet of the present invention's design.The measurement result of magnet character is listed in table 4, and table 4 has also been listed the character (comparative examples) of only carrying out phase I heat treatment example.

Table 4

(composition)	Remanent magnetism (KG)	Coercive force (KOe)	Maximum magnetic energy product (MGOe)
				76Fe9B15Nd	5.4	12.4	6.0
79Fe7B14Nd	5.6	13.0	6.2
				78Fe8B12Nd2Gd	5.6	12.3	5.9
76Fe9B15Nd (for the first time after the burin-in process)	5.2	6.9	5.2
				79Fe7B14Nd (after the phase I burin-in process)	5.3	7.4	5.1

Example 5

By obtain a kind of Fe-B-R alloy that is listed in the table below by the atomic percent composition at argon gas medium-high frequency method of smelting, cast with a water-cooled copper mould.

This alloy is slightly ground with bruisher, makes granular size be not more than 35mesh, in certain organic solvent, carry out fine grinding with ball mill then, make its reach mean particle size be 3 microns to resulting powder, in 12KOe magnetic field, with 1.5ton/cm ²Pressure carry out press molding, in purity is the argon gas of 99.99%, 200 torr air pressure, carry out sintering subsequently, sintering temperature is 1080 ℃, continues 2 hours, then the cooldown rate with 500 ℃/min makes it to be quickly cooled to room temperature.

Thereafter, burin-in process one hour under 800 ℃ of conditions in 760 torr argon gas, next with the cooldown rate of 300 ℃/min its cool to room temperature, under 620 ℃ of conditions, further carry out 3 hours burin-in process again, to obtain the magnet of the present invention's design.The character of this magnet is listed in table 5, and table 5 has also been listed the character (behind the sintering) of comparative example.

Table 5

(composition)	Remanent magnetism (KG)	Coercive force (KOe)	Maximum magnetic energy product (MGOe)
				79.5Fe6.5B14Nd	13.7	10.2	44.2
(79.5Fe6.5B14Nd reference examples is behind the sintering)	13.6	7.2	41.4

Example 6

To obtain a kind of composition be the alloy of 62Fe6B16Nd16Co by the percentage of atom by carry out the high frequency melting in argon gas, casts with a water-cooled copper mold.With bruisher this alloy is slightly ground, make its granular size be not more than 35mesh, carry out fine grinding with ball mill in argon gas atmosphere then, making it reach mean particle size is 3 microns.Again in the magnetic field of 15KOe with 2.0ton/cm ²Pressure carry out press molding, then in purity is the argon gas of 99.99%760 torr air pressure, carry out sintering, sintering temperature is 1100 ℃, continues to make it cool to room temperature with the cooldown rate of 500 ℃/min subsequently in 2 hours.And then in argon gas atmosphere, carry out burin-in process under 800 ℃ of conditions, the desirable different value of ageing treatment time.In cooldown rate it has been cooled to after 500 ℃, under 580 ℃ of conditions, has carried out further burin-in process again, continued 2 hours, to obtain the designed magnet of the present invention with 400 ℃/min.The magnetic of product the results are shown in table 6, and table 6 gives the magnetic data of reference examples, and reference examples is through aging magnet of 1 hour single phase under 800 ℃ of conditions.Table 6 also listed the present invention's design magnet residual magnetic flux density temperature coefficient a(%/℃), list file names with the relevant temperature coefficient value of the reference examples magnet that only passes through the single phase burin-in process.

Table 6

Example 7

Can obtain a kind of alloy that its composition atomic percent is 60Fe12B15Nd3Y10Co by the melting of argon gas arc process.With a water-cooled copper mold above-mentioned alloy is cast.Resulting alloy is slightly ground with bruisher, make its granular size be not more than 50mesh, carry out fine grinding with ball mill in certain organic solvent again, making it mean particle size is 2 microns.Resulting powder is used 2.0ton/cm again in the magnetic field of 10KOe ²Pressure carry out the sintering that press molding then carried out 2 hours in purity is the argon gas of 99.99%, 200 torr air pressure, sintering temperature is 1150 ℃, the cooldown rate of 150 ℃/min makes it cool to room temperature subsequently.The temperature of phase I burin-in process is got different values, lists in table 7 and will be 2 * 10 ^-5Vacuum condition under carry out, the cooldown rate with 350 ℃/min makes it to be cooled to 350 ℃ then.Under 620 ℃ conditions carry out 4 hours second stage burin-in process, to obtain the magnet of the present invention's design thereafter.The temperature coefficient a(% of the magnetic of this magnet, residual magnetic flux density (Br)/℃) value all lists table 7 in, table 7 is also listed the corresponding data of reference examples (after a stage burin-in process).

Table 7

Example 8

Several its compositions that obtain by melting in argon gas electric arc are by atomic percent FeBRCo alloy as shown in table 8.Cast with a water-cooled copper mold respectively.The alloy that obtains is slightly ground in bruisher, make its granular size be not more than 40mesh, carry out fine grinding with ball mill in certain organic solvent again, making its mean particle size is 4 microns.Resulting powder is used 1.5ton/cm in 15KOe magnetic field ²Pressure carry out press molding, in purity is the argon gas of 99.99%, 200 torr air pressure, carry out 2 hours sintering then, sintering temperature is 1080 ℃, then the cooldown rate with 400 ℃/min is cooled fast to room temperature.Under 850 ℃ of conditions, carry out 2 hours phase I burin-in process in the argon gas of 600 torr air pressure subsequently, next the cooldown rate with 200/min makes it to be cooled to 350 ℃., under 650 ℃ conditions carry out 2 hour second stage heat treatment, to obtain the magnet of the present invention's design thereafter.The magnetic of this magnet, the temperature coefficient a(% of Br/℃) list in table 8, table 8 is also listed the corresponding data of the reference examples of only passing through the single phase burin-in process.

Table 8

Example 9

Obtain its composition by some following FeBRCo alloys of atomic percent by the melting of argon gas arc method, cast with a water-cooled copper mold.These alloys are slightly ground with bruisher, make its granular size be no more than 25mesh, carrying out fine grinding with ball mill in certain organic solvent again, to make its mean particle size be 3 microns.Then under without any the condition in magnetic field with 1.5ton/cm ²Pressure resulting alloy powder is carried out press molding, in purity is the argon gas of 99.99%250 torr air pressure, carry out 2 hours sintering again, sintering temperature is 1030 ℃.After sintering, be cooled fast to room temperature next under 840 ℃ of conditions with the cooling rate of 300 ℃/min, carry out 4 hours phase I burin-in process in the argon gas of 650 torrs, the cooldown rate with 350 ℃/min is cooled to 450 ℃ to it subsequently.Under 650 ℃ conditions carry out 2 hours second stage burin-in process, to obtain the magnet of the present invention's design thereafter.The magnetic data of this magnet is listed in table 9, and table 9 has also been listed and only passed through the phase I burin-in process example (corresponding data of reference examples.

Table 9

Example 10

Obtain its composition by some following FeCoBR alloys of contained atomic percent by fusing in argon gas electric arc, cast with a water-cooled copper mold.

The alloy that obtains is slightly ground in bruisher, make its granular size be no more than 35mesh and carry out fine grinding with ball mill in certain organic solvent again, making its mean particle size is 3 microns.To resulting alloy powder in the magnetic field of 12KOe with 1.5ton/cm ²Pressure carry out press molding, in purity is the argon gas of 99.99%, 200 torr air pressure, carry out 2 hours sintering then, sintering temperature is 1080 ℃, next the cooldown rate with 500 ℃/min is quickly cooled to room temperature.

Burin-in process is to carry out in the argon gas of 800 ℃ of temperature, 760 torrs, and the time is 1 hour, subsequently with the cooldown rate cool to room temperature of 300 ℃/min.Then, under 580 ℃ of conditions, carry out 3 hours the burin-in process second time, to obtain the designed magnet of the present invention.This magnetic data is listed in table 10, and table 10 is also listed the corresponding data of Comparative Examples.(this Comparative Examples is after sintering)

Table 10

Example 11

A kind of composition is the alloy of BalFe-8B-16Nd-2Ta-1Sb by the percentage of contained atom, is 1.8 microns powder to the mean particle size of this alloy, in the magnetic field of 15KOe with 1.5Ton/cm ²Pressure carry out press molding, be sintering 2 hours in the argon gas of 99.99%250 torrs then in purity, sintering temperature is 1080 ℃, the cooldown rate with 600 ℃/min makes it cool to room temperature subsequently.Burin-in process is in argon atmospher, carries out with the different time under 780 ℃ of conditions, and the cooldown rate with 360 ℃/min is cooled to 480 ℃ to it then.Then, carry out 2 hours the burin-in process second time again under 560 ℃ of conditions, to obtain the magnet of the present invention's design, its magnetic the results are shown in table 11, table 11 has also been listed the data of reference examples, and this reference examples is only carried out 1 hour single phase burin-in process under 780 ℃ of conditions.

Table 11

Example 12

Alloy composition is some alloy powders of Br1Fe-10B-13Nd-3Pr-2W-1Mn by the percentage of contained atom, and its mean particle size is 2.8 microns.To this alloy powder in the magnetic field of 10KOe with 1.5Ton/cm ²Pressure carry out press molding, in purity is the argon gas of 99.999%, 280 torrs, carry out 2 hours sintering then, sintering temperature is 1120 ℃, then with the cooldown rate cool to room temperature of 500 ℃/min.Thereafter 4 * 10 ^-6Under the vacuum condition of torr, carry out the phase I burin-in process with different temperature (listing in table 12), continue two hours, cooldown rate with 320 ℃/min is cooled to be not more than 600 ℃ temperature to it again, the second stage burin-in process is carried out under 620 ℃ of conditions then, time is 8 hours, to obtain the permanent magnet of the present invention's design.Its magnetic the results are shown in table 12, and table 12 is also listed the corresponding data of reference examples.(this reference examples through the second stage burin-in process after)

Table 12

Example 13

Some Fe-B-R-M alloy powders, its composition is listed in table 13 by contained atomic percent, mean particle size is 1 to 6 micron, to these alloy powders in the magnetic field of 15KOe, with 1.2Ton/cm ²Pressure carry out press molding, in purity is the argon gas of 99.999%, 180 torrs, carry out two hours sintering again, sintering temperature is 1080 ℃, then the cooldown rate with 650 ℃/min makes it to be quickly cooled to room temperature.Then, under 775 ℃ of conditions, carry out 2 hours burin-in process in high-purity, 550 argon gas, the cooldown rate with 280 ℃/min makes it to be cooled to not be higher than 550 ℃ again.After this, under 640 ℃ of conditions, carry out 3 hours second stage burin-in process, to obtain the permanent magnet of the present invention's design.Its magnetic data is listed in table 13, and table 13 is also listed the corresponding data (this reference examples is through single phase heat treatment) of reference examples.

Table 13

Example 14

Be the Fe-B-R-M alloy powder of following situation by contained atomic percent in the composition, mean particle size is 2 to 8 microns, to this powder under without any the situation in magnetic field with 1.0Ton/cm ²Pressure carry out press molding, in purity is the argon gas of 99.999%, 180 torrs, carry out two hours sintering, sintering temperature is 1080 ℃, the cooldown rate with 630 ℃/min is quickly cooled to room temperature subsequently.Then, under 630 ℃ of conditions, carry out 4 hours phase I burin-in process in carrying out in the argon gas of 350 torrs, cooldown rate with 220 ℃/min makes it to be cooled to not be higher than 550 ℃ then, and then under 580 ℃ of conditions, carry out 2 hours second stage heat treatment, to obtain the permanent magnet of the present invention's design.Its magnetic data is listed in table 14, and table 14 is also listed the corresponding data of reference examples.(this reference examples was only carried out the phase I burin-in process)

Table 14

Example 15

The Fe-B-R-M alloy that has the listed composition of following table by contained atomic percent obtains by the method in the fusing of argon gas medium-high frequency, casts with a water-cooled copper mold.

Resulting alloy slightly grinds with bruisher, make its granular size be not more than 35mesh, carry out fine grinding with ball mill in certain organic solvent again, making its mean particle size is 2.7 microns alloy powders to obtaining like this, in the magnetic field of 12KOe, with 1.5Ton/cm ²Pressure carry out press molding, in purity is the argon gas of 99.99%, 200 torrs, carry out 2 hours sintering again, sintering temperature is 1080 ℃, then the cooldown rate with 500 ℃/min makes it to be quickly cooled to room temperature.

Thereafter, at 800 ℃, carry out 1 hour burin-in process in the argon gas of 760 torrs, the cooldown rate with 300 ℃/min makes it to be cooled to room temperature again, and the burin-in process of second stage continues 3 hours under 620 ℃ of conditions, to obtain the magnet of the present invention's design.Its magnetic data is listed in table 15, and table 15 has also been listed the corresponding data of reference examples (behind the sintering).

Table 15

Example 16

By its composition of contained atomic percent is the alloy powder of BalFe-12Co-9B-14Nd-1Mo, and its mean particle size is 35 microns, to this powder in 12Koe magnetic field with 1.3Ton/cm ²Pressure carry out press molding, in purity is the argon gas of 99.99%, 200 torrs, carry out 2 hours sintering again, sintering temperature is 1120 ℃, makes it to be cooled to room temperature in the cooldown rate with 650 ℃/min then.Thereafter, under 820 ℃ of conditions, carry out burin-in process with different temperature in argon gas atmosphere, the cooldown rate with 350 ℃/min is cooled to 480 ℃ again, then carries out two hours second stage heat treatment under 600 ℃ of conditions, to obtain the magnet of the present invention's design.The temperature coefficient a(% of its magnetic data and residual magnetic flux density (Br)/℃) list in the table 16, table 16 is also listed the corresponding data of the magnet that has only carried out 820 ℃ * 1 hour single phase burin-in process.

Table 16

Example 17

By its composition of contained atomic percent is the alloy powder of Ba1Fe-18Co-10B-14Nd-1Y-2Nd-1Ge, and mean particle size is 2.8 microns, to this powder in the magnetic field of 12KOe, with 1.2Ton/cm ²Pressure carry out press molding, in purity is the argon gas of 99.999%, 500 torrs, carry out two hours sintering again, sintering temperature is 1140 ℃, then with the room temperature that is cooled to of the cooldown rate of 400 ℃/min.Then, 5 * 10 ^-5Carry out in the vacuum of torr 2 hours different temperatures (listing in table 17) the phase I burin-in process, cooldown rate with 400 ℃/min is cooled to 420 ℃ then, under 580 ℃ of conditions, carry out 3 hours second stage burin-in process again, to obtain the magnet of the present invention's design, the temperature coefficient a(% of its magnetic data and residual magnetic flux density (Br)/℃) list in table 17, table 17 is also listed the reference examples corresponding data of (through the phase I burin-in process).

Table 17

Example 18

The powder of Fe-Co-B-R-M alloy, the percentage of contained atom is listed in table 18 in its composition, and its mean particle size is 2 to 8 microns.To this powder under the condition of 12KOe with 1.2Ton/cm ²Pressure carry out press molding, in purity is the argon gas of 99.999%, 200 torrs, carry out two hours sintering again, sintering temperature is 1100 ℃, then the cooldown rate with 750 ℃/min is quickly cooled to room temperature.Burin-in process was carried out two hours under 820 ℃ of conditions, in the argon gas of 450 torrs first, cooldown rate with 250 ℃/min makes it to be cooled to 380 ℃ then, under 600 ℃ of conditions, carry out two hours second stage burin-in process then, to obtain the magnet of the present invention's design.The temperature coefficient a(% of the numerical value of its magnetic and Br/℃) list in table 18, table 18 has also been listed the corresponding data that only carries out phase I burin-in process reference examples.

Table 18

Example 19

The Fe-CoB-R-M alloy powder, its composition is as shown in the table, and its mean particle size is 1 to 6 micron.To this powder without any under the magnetic field condition with 1.2Ton/cm ²Pressure carry out press molding.Carry out two hours sintering again in purity is the argon gas of 99.999%, 180 torrs, sintering temperature is got 1080 ℃, and the cooldown rate with 630 ℃/min is quickly cooled to room temperature subsequently.Burin-in process was carried out 4 hours in 850 ℃ of 700 torr argon gas first, and then the cooldown rate with 380 ℃/min makes it to be cooled to 420 ℃, carries out 3 hours second stage burin-in process then under 620 ℃ of conditions, to obtain the magnet of the present invention's design.Its magnetic the results are shown in table 19, and table 19 has also been listed the corresponding data that does not have through the example (reference examples) of second stage burin-in process.

Table 19

Example 20

By the alloy that the method for carrying out the high frequency fusing in argon gas obtains, the contained atomic percent of its composition is as shown in the table, casts with a water cooling copper mold.

On bruisher, these alloys are slightly ground earlier, make its granular size be no more than 35mesh and in certain organic solvent, carry out fine grinding with ball mill again, make its mean particle size be 2.6 microns in the magnetic field of 12KOe with 1.5ton/cm ²Pressure carry out press molding, in purity is the argon gas of 99.999%, 200 torrs, carry out 2 hours sintering again, sintering temperature is got 1080 ℃, then the cooldown rate with 500 ℃/min is quickly cooled to room temperature.

Carry out one hour burin-in process under 800 ℃ of conditions, in the 760 torr argon gas, the cooldown rate with 300 ℃/min is cooled to room temperature subsequently, carries out 3 hours second stage burin-in process again under 580 ℃ of conditions, to obtain magnet of the present invention.Its magnetic data is listed in table 20, and table 20 has also been listed the corresponding data of reference examples (behind the sintering).

Table 20

Claims

1, permanent magnet, its maximum magnetic energy product (BH) max is 30MGOe at least, coercive force is 13KOe at least, comprises the following steps: in its preparation method

It is 8～30% R (supposition R is one of rare earth element that comprises Y at least) by the percentage of contained atom that a kind of composition is provided, 2～28% B, surplus is the sintered body of Fe, sintered body carried out phase I heat treatment and in the second stage heat treatment that is lower than under the phase I heat treatment temperature, it is characterized in that

Under 750～1000 ℃ condition, carry out phase I heat treatment,

The gained sintered body is cooled to not be higher than 680 ℃ temperature with the cooldown rate of 20～2000 ℃/min,

Under 480～700 ℃ condition, carry out second stage heat treatment,

Wherein R is that 13-16% and B are 6-11%.

2, permanent magnet, its maximum magnetic energy product (BH) max comprises the following steps: in its preparation method for 30MGOe coercive force at least is 13KOe at least

It is that 8～30% R(supposition R is one of rare earth element that comprises Y at least by the percentage of contained atom that a kind of composition is provided), 2～28% B, except no more than 50% the Co(O%), surplus is the sintered body of Fe, sintered body carried out phase I heat treatment and in the second stage heat treatment that is lower than under the phase I heat treatment temperature, it is characterized in that

Under 750～1000 ℃ condition, carry out phase I heat treatment,

Under 480～700 ℃ condition, carry out second stage heat treatment,

Wherein R is that 13-16 and B are 6-11%.

3, permanent magnet, its maximum magnetic energy product (BH) max is 30MGOe at least, coercive force is 13KOe at least, comprises the following steps: in its preparation method

It is that 8～30% R(supposition R comprises at least a in the rare earth element of Y by the percentage of contained atom that a kind of composition is provided), 2～28% B, at least a additional elements M, the content of additional elements are no more than given percentage (except 0%), and additional elements M is:

Be no more than 9.5% V, be no more than 12.5% Nb,

Be no more than 10.5% Ta, be no more than 9.5% Mo,

Be no more than 9.5% W, be no more than 8.5% Cr,

Be no more than 9.5% Al, be no more than 4.5% Ti,

Be no more than 5.5% Zr, be no more than 5.5% Hf,

Be no more than 8.0% Mn, be no more than 8.0% Ni,

Be no more than 7.0% Ge, be no more than 3.5% Sn,

Be no more than 5.0% Bi, be no more than 2.5% Sb,

The Zn that is no more than 5.0% Si and is no more than 2.0%, just require when comprising two or more M, its total amount is not greater than the given maximum percentage composition of each additional elements (as top comprising), surplus is the sintered body of Fe, sintered body carried out phase I heat treatment and in the second stage heat treatment that is lower than under the phase I heat treatment temperature, it is characterized in that

Under 750～1000 ℃ condition, carry out phase I heat treatment,

Under 480～700 ℃ condition, carry out second stage heat treatment,

Wherein R is that 13-16% and B are 6-11%.

4, permanent magnet, its maximum magnetic energy product (BH) max is 30MGOe at least, coercive force is 13KOe at least, comprises the following steps: in its preparation method

It is that 8～30% R(supposition R is at least a element that comprises in the rare earth element of Y by the percentage of contained atom that a kind of composition is provided), 2～28% B, except no more than 50% the Co(0%), at least a additional elements M, the content of additional elements are no more than given percentage (except 0%):

Be no more than 9.5% V, be no more than 12.5% Nb,

Be no more than 10.5% Ta, be no more than 9.5% Mo,

Be no more than 9.5% W, be no more than 8.5% Cr,

Be no more than 9.5% Al, be no more than 4.5% Ti,

Be no more than 5.5% Zr, be no more than 5.5% Hf,

Be no more than 8.0% Mn, be no more than 8.0% Ni,

Be no more than 7.0% Ge, be no more than 3.5% Sn,

Be no more than 5.0% Bi, be no more than 2.5% Sb,

Be no more than 5.0% Si and be no more than 2.0% Zn,

As long as when comprising two or more M, its total amount is not greater than maximum percentage composition given among each additional elements M (listed as mentioned), surplus is the sintered body of Fe, sintered body carried out phase I heat treatment and in the second stage heat treatment that is lower than under the phase I heat treatment temperature, it is characterized in that

Under 750～1000 ℃ condition, carry out phase I heat treatment,

Under 480～700 ℃ condition, carry out second stage heat treatment,

Wherein R is that 13-16% and B are 6-11%.