CN1658339A - Cohesive composite permanent magnetic material containing neodymium iron nitrogen and its preparation method - Google Patents
Cohesive composite permanent magnetic material containing neodymium iron nitrogen and its preparation method Download PDFInfo
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- CN1658339A CN1658339A CN 200410088953 CN200410088953A CN1658339A CN 1658339 A CN1658339 A CN 1658339A CN 200410088953 CN200410088953 CN 200410088953 CN 200410088953 A CN200410088953 A CN 200410088953A CN 1658339 A CN1658339 A CN 1658339A
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Abstract
This invention relates to a flexible adhesive magnetic material, especially an adhesive built-up permanent magnet containing Nd, Fe and N2, which has the permanent magnet powder with the weight ratio of 85-97%, the power at least has 10% permanent magnet powder of Nd, Fe and N2, 2-12% agglomerate and 1-3% fitting agent; this invention also provides with the manufacturing technique of this built-up permanent magnet; the products have the characteristics of good magnetic capacity, strong stretching power, oxidation-resistant and good flexibility.
Description
Technical field
The present invention relates to permanent magnetic material, specifically, be a kind of flexible adhesion magnet class material, especially a kind of novel the cohesive composite permanent magnetic body and the manufacturing process thereof that contain neodymium iron nitrogen, this product has the magnetic property height, and hot strength, non-oxidizability, pliability, characteristics that pliability is all good.
Background technology
Bonded permanent magnet has been widely used in the automatic field of household electrical appliances, computer, automobile, processing and factory since coming out; Rapid emergence along with the IT industry of the develop rapidly of industries such as global information, electronics, traffic and China, computer, auto industry and consumer electronics market also will present rapid growth trend to the demand of high performance magnetic material, the demand of making various small and special electric machines and magnetic device etc. is also increasing, and bonded permanent magnet every year, the ratio with about 30% increased.In existing bonded permanent magnet, generally be to adopt neodymium iron boron (NdFeB) Magnaglo, on the performance of NdFeB permanent-magnet powder, it has the burn into of being easy to and is easy to multiple shortcomings such as oxidation, also will add anticorrosion, anti-oxidation etc. technological process at manufacture craft last when making various magnets; And this magnetic price is in a kind of state of monopolization always, thereby the bonding NdFeB that causes making series composite permanent magnet price is corresponding higher, also certain for increasing the fringe cost that anticorrosion, anti-oxidation etc. technology increase on expensive like this with regard to having increased, moreover in anti-oxidation etc. the technological process of anticorrosion, can there be many technology and environmental issue, more problem will occur in the process of whole like this making magnet, thereby make the magnet of manufacturing often have many technological deficiencies; In addition, because NdFeB permanent-magnet powder particle is thick, product pliability and the pliability made are poor.
The professor of Peking University, the academician Yang Yingchang of the Chinese Academy of Sciences etc. have invented 1:12 type neodymium-iron-nitrogen compound series, application number: 90109166.9, and this 1:12 type neodymium-iron-its molecular formula of nitrogen compound series is NdFe
12-xM
xN
y, wherein M is Ti (titanium), Mo (molybdenum) or W (tungsten); X=1～2; Y=3～7, on the performance of inventing disclosed product (being magnetic), this magnetic has overcome the many disadvantages of NdFeB series composite permanent magnet, have following characteristics: 1. few because of the rare earth relative amount, and the metal that the cobalt that undopes etc. are expensive, and by China oneself research and development have China's independent intellectual property right, so cost is low; 2. resistance to corrosion, oxidation resistance are strong, and having avoided general by nitrogenize is the weakness of the easy oxidation of the easy burn into of permanent magnetic material of base with the rare-earth-iron; 3. compare tiny, the even particle size distribution of powder particle with neodymium iron boron; 4. not only at normal temperatures, and at low temperatures also demonstrate the excellent magnetism energy.
Therefore, thereby developing the permanent magnetic material that a kind of new permanent magnet substitutes neodymium iron boron, is that the problem that solves is expected in this area always.In a sense, neodymium iron nitrogen permanent magnetic material is unique permanent magnetism compound of competing mutually with neodymium iron boron of being expected to.
Summary of the invention
In order to solve some defectives that existing magnet exists, the inventor provides a kind of novel neodymium iron nitrogen that contains, and (be expressed as NdFeN, preferred molecular formula is NdFe
12-xM
xN
y, wherein M is Ti, Mo or W; X=1～2; Y=3～7) cohesive composite permanent magnetic body and manufacturing process thereof, the permanent-magnet powder and the binding agent that contain NdFeN by employing are compositely suppressed to form, and have the magnetic property height, and hot strength, non-oxidizability, pliability, characteristics that pliability is all good.
The object of the present invention is to provide a kind of cohesive composite permanent magnetic material that contains neodymium iron nitrogen, this material use NdFeN substitutes NdFeB wholly or in part as raw material, make product have the magnetic property height, and hot strength, non-oxidizability, pliability, characteristics that pliability is all good.
The present invention also aims to provide a kind of preparation method who contains the cohesive composite permanent magnetic material of neodymium iron nitrogen, the permanent-magnet powder and the binding agent (rubber or haloflex) that contain NdFeN by employing are compositely suppressed to form, make product have good magnetic performance, and all good characteristics of good hot strength, non-oxidizability, pliability and pliability.
The invention provides a kind of cohesive composite permanent magnetic material that contains neodymium iron nitrogen, wherein: weight ratio is 85～97% permanent-magnet powder, and it contains 10% neodymium iron nitrogen (being) permanent-magnet powder at least; 2～12% binding agent and 1～3% compounding ingredient, described binding agent are rubber or haloflex, and compounding ingredient comprises coupling agent, reinforcing filler, age resistor and plasticising lubricant.
The present invention also provides the above-mentioned preparation method who contains the cohesive composite permanent magnetic material of neodymium iron nitrogen, and its step comprises:
Be that the coupling agent of permanent-magnet powder and 0.1～0.8% mixes with alcohol, organic solvent of ketone (as alcohol, acetone etc.) and coats processing, drying with the neodymium iron nitrogen of weight ratio 85～97%;
With coat good permanent-magnet powder and binding agent and other compounding ingredients send into carry out in the banbury mixing, mixing evenly after, use twin-screw extruder mixing again;
Be pressed into thin slice, build up required finished product thickness.
The present invention adopts the permanent-magnet powder contain NdFeN and binding agent as raw material, through compound suppressing, develop the composite permanent magnet of a kind of NdFeN of containing, it is a kind of flexible adhesion magnet, and this product is corrosion-resistant, anti-oxidant, heat-resisting, oil resistant, solvent resistance is good and combination properties such as mechanical performance, physical property, magnetic property and apparent property are all good.
The required temperature of above-mentioned steps can be conventional temperature, and for example, the temperature of banbury is preferably 80～120 ℃, the roller temperature is 50～100 ℃, the roller temperature of preferred mill is a little less than the roller temperature of banbury, and for example banbury roller temperature is 60～100 ℃, and the roller temperature of mill is 50～90 ℃; The thickness of thin slice is preferably 1～3mm.
When binding agent is rubber, be pressed into thin slice, build up the step that required finished product thickness also can comprise sulfuration afterwards, described sulfuration comprises hot-air cure or the frame sulfuration is arranged that curing temperature is preferably 140～170 ℃.
The above-mentioned cohesive composite permanent magnetic material that contains neodymium iron nitrogen contains the permanent-magnet powder of 10% neodymium iron nitrogen (being) at least in the permanent-magnet powder that wherein contains, this permanent-magnet powder can be 100% NdFeN; Also can be NdFeN system and ferrite series composite permanent-magnet powder; Can also be NdFeN system, ferrite system and NdFeB series composite permanent-magnet powder.When using the composite permanet magnet powder, can the assembly of broad ratio form between each composition, but being permanent-magnet powder, NdFeN is at least 10% of permanent-magnet powder total weight, preferred more than 50%.
In a preferred embodiment, the permanent-magnet powder that contains NdFeN that the present invention is mentioned can be self-control or any commercially available NdFeN permanent-magnet powder, preferred 1:12 type neodymium-iron-nitrogen compound series, and molecular formula is NdFe
12-xM
xN
y, wherein M is Ti (titanium), Mo (molybdenum), W (tungsten); X=1～2; The 1:12 type neodymium-iron-nitrogen compound series disclosed in 90109166.9 for example can preferably be adopted in y=3～7; Ferrite is that permanent magnetism is strontium ferrite or barium ferrite, and its molecular formula is respectively SrO6Fe
2O
3And BaO6Fe
2O
3NdFeB is that permanent-magnet powder is 2:14 type neodymium-iron-boron compound series, and its molecular formula is Nd
2(Fe
1-xM
x)
14B, wherein, M is Co (cobalt), Ni (nickel), Si (silicon), Cr (chromium), Al (aluminium), Mn (manganese) or Ru (ruthenium), X=0～1.The total weight content of permanent-magnet powder that contains NdFeN system in the composite permanent magnet of the present invention is 85～97%, when this permanent-magnet powder is the compound tense of two or three permanent-magnet powder, the content of this two or three powder component is adjustable in the aforementioned proportion scope, but requires NdFeN must not be less than 10%.
NdFeN in the raw material of the present invention (being) permanent-magnet powder has following characteristics: 1. the rare earth relative amount is few, and expensive metal such as the cobalt that undopes, and cost is low; 2. having avoided general by nitrogenize is the weakness of the easy burn into of the permanent magnetic material easy oxidation of base with the rare-earth-iron, and resistance to corrosion, oxidation resistance are strong; 3. the tiny and even particle size distribution of powder particle, the permanent magnet apparent property of making is good, smooth, smooth not to fall slag, and mechanical property is good, and deflection degree is big, and can arbitrarily bend and curl and the surface does not crack and crack, the hot strength height, elongation is big.4. not only at normal temperatures, and at low temperatures also demonstrate the excellent magnetism energy.
The above-mentioned cohesive composite permanent magnetic material that contains neodymium iron nitrogen, wherein binding agent is rubber or haloflex, and described rubber comprises and is selected from least a in natural rubber (NR), acrylonitrile-butadiene rubber (NBR), neoprene (CR), silicon rubber (MVQ), ethylene-propylene rubber (EPDM), chlorosulfonated polyethylene (CSM), butadiene-styrene rubber (SBR), butyl rubber (ACM), polyisoamylene rubber (IR) and the fluorubber (FPM).
Compounding ingredient all plays crucial effects on the preparation of the cohesive composite permanent magnetic body that contains NdFeN and performance, compounding ingredient of the present invention comprises coupling agent, reinforcing filler, age resistor, plasticising lubricant etc.
Wherein when binding agent was rubber, compounding ingredient was preferably coupling agent, vulcanizing agent, vulcanization aid, reinforcing filler, age resistor and plasticising lubricant; When binding agent was haloflex, compounding ingredient was preferably coupling agent, age resistor, plasticising lubricant and reinforcing filler.
Coupling agent mainly is silanes or metatitanic acid lipid, accounts for 0.1～0.8% of permanent magnet total weight ratio; Vulcanizing agent claims cross linking agent again, kind is a lot, optional bin cure and congeners thereof (as: sulphur, selenium and tellurium etc.), peroxide (organic peroxide especially, as peroxidating toluoyl (BPO) and cumyl peroxide (DCP) etc.), metal oxide (as: zinc oxide and magnesium oxide etc.), preferred sulphur, selenium, tellurium or cumyl peroxide (DCP) etc., more preferably sulphur or cumyl peroxide (DCP); Vulcanization aid is meant the compounding ingredient that helps sulfuration process, its adding can promote the vulcanization reaction of magnetic rubber widely, improve curingprocess rate, reduce curing temperature and shorten cure time, improve the physical and mechanical properties of magnetic rubber simultaneously, thiazoles (as: 2-mercaptobenzothiazole (M) or benzothiazole disulfide (DM) etc.) is generally arranged, thiurams (as: tetramethylthiuram disulfide (TMTD), tetramethylthiuram monosulfide (TMTM) etc.), sulfenamide (as: N-ring ethyl-2-[4-morpholinodithio base time sulphamide (CZ), N, N-dicyclohexyl-2-[4-morpholinodithio time sulphamide (DZ)) etc., reinforcing filler mainly is the hot strength that improves product, hardness and the function that reduces cost, the reinforcing filler that the sticking rubber magnet is used mainly is carbon black and white carbon, potter's clay, talcum powder and calcium carbonate etc., carbon black is most important reinforcing agent, mainly form by carbon, Stability Analysis of Structures, particle diameter is little, specific area is big, has good strengthening action, white carbon belongs to inorganic filler, and reinforcing effect is similar to carbon black; Age resistor is meant and prevents that product is in processing and manufacturing, long term storage and use, owing to effects such as being subjected to oxygen, ozone, variable valency metal ions, light and heat makes the product modification, mainly contain amine (as: 2,2,4-trimethyl-1,2-dihyaroquinoline condensate (RD)), phenols (as: styrenated phenol (SPH)) etc.; The plasticising lubricant is meant mixing in machining process, calendering, can improve its plasticity when extrusion and moulding, the compounding ingredient of lubrification, make product have good processing properties, generally comprise mineral oils, three kinds of animals and plants oils and synthetic classes, mineral oil has paraffin, vaseline, Petropols etc., animals and plants oils has pine tar, aliphatic acid and fatty wet goods, synthetic class have epoxy compounds (fat oil system to be arranged, stearic acid system and tetrahydrophthalic acid lipid) and the polyesters compound (as the stupid dibutyl carboxylic acid of neighbour (DBP), dioctyl phthalate (DOP)).The summation of compounding ingredients such as above-mentioned vulcanizing agent, vulcanization aid, reinforcing filler, age resistor, plasticising lubricant accounts for 0.9～2.2% of permanent magnet total weight ratio.
The cohesive composite permanent magnetic body that contains neodymium iron nitrogen of the present invention, it has good magnetic property, and its remanent magnetism Br is 0.30～0.70T, and magnetic strength coercivity H b is 200～500kA/m, HCJ Hcj is 300～800kA/m, and maximum magnetic energy product (BH) max is 15～56kJ/m
3
Technical scheme of the present invention realizes by following steps:
1. be that the coupling agent of 85～97% neodymium iron nitrogen series permanent-magnet powder and 0.1～0.8% mixes with organic solvent (for example: alcohol, acetone etc.) and coats processing, drying with weight ratio;
2. will coat good permanent-magnet powder and binding agent and other compounding ingredients send into carry out in the banbury mixing, mixing evenly after, use twin-screw extruder mixing again; Perhaps will coat good permanent-magnet powder and binding agent and other compounding ingredients and send into and open refining in the mill, open after the refining evenly, and use twin-screw extruder mixing again;
3. be pressed into thin slice, build up required finished product thickness, get final product.
Wherein the mixing temperature of step (2) banbury is 80～120 ℃, 60～100 ℃ of roller temperature, and 50～90 ℃ of the roller temperature of mill, the thickness of step (3) thin slice is 1～3mm, the roller temperature is 50～80 ℃.
Among the above-mentioned preparation method of the present invention, when binding agent is rubber, also need increase the step of sulfuration afterwards in step (3).Sulfuration makes the rubber macromolecule of linear condition become solid netted rubber molecular chain, thereby makes the sticking rubber magnet obtain splendid physics, mechanical performance.Vulcanization process is a lot, and the vulcanization process that the present invention preferably adopts can be hot-air cure or the frame sulfuration is arranged.When selecting hot-air for use or the frame sulfuration is arranged, cure time was generally 20～40 minutes, and curing temperature is generally 140～170 ℃.
The shape of product degree of freedom that above-mentioned technology makes is big, can be processed into tabular, sheet, strip, ring-type, bar-shaped and multiple other shaped etc. as required, and apparent property is good, and it is simple that the operating aspect product size is easy to control, precision height and production technology.
Above-mentioned optimal process of the present invention is:
1. coating operation: the ratio 85～97% (total weight ratio) in the NdFeN permanent-magnet powder weighs up weight, (coupling agent accounts for 0.1～0.8% of total weight to weigh up coupling agent in proportion, it is silanes or phthalandione lipid), the coupling agent and the organic solvent that weigh up are evenly mixed, put into the composite permanet magnet powder then and evenly mix at mixer and coat processing, deliver in the vacuum tank it dry after treating evenly.Such treatment process has not only improved magnetic with affinity rubber but also improved the final various combination properties of magnetic.
2. manufacturing process: weigh up binding agent (by the permanent magnet total weight 2～12%), other compounding ingredient (when binding agent is rubber, also comprises vulcanizing agent, adopts sulphur, selenium, tellurium and other sulfide etc.; Vulcanization aid, vulcanization aid have thiazoles, thiurams, sulfenamide etc.; These compounding ingredients except that coupling agent account for altogether permanent magnet total weight ratio 0.9～2.2%), good Magnaglo will be coated, binding agent and described compounding ingredient send into carry out in the banbury mixing, mixing evenly after, with itself and the rubber or the haloflex of the accurate weighing of content on request, compounding ingredient mixes in banbury (80～120 ℃), use twin-screw extruder (the roller temperature control is at 60～100 ℃) mixing again, the mixing thin slice that adopts after last slice two roll calender (the roller temperature control is at 50～80 ℃) to be pressed into 1～3mm thickness adopts calender (the roller temperature control is at 50～80 ℃) to build up required finished product thickness according to finished product thickness then; Perhaps will coat good permanent-magnet powder and binding agent and above-mentioned compounding ingredient and send into and open refining in the mill, the roller temperature is preferably 50～90 ℃, opens after the refining evenly, uses twin-screw extruder mixing again; Be pressed into thin slice, build up the finished product desired thickness.
The step that when selecting rubber for use, also need vulcanize at last as binding agent.
This novel cohesive composite permanent magnetic body that contains neodymium iron nitrogen of the present invention (also claiming neodymium iron nitrogen series composite permanent-magnet body) at first has the good mechanical performance of elastomeric material, physical property and chemical characteristic, the hot strength height, hot strength 〉=5.0MPa, elongation is big, the δ value is between 20～200%, and pliability is good, and pliability is good, goods can be done and optionally bend and curl, bending and curl after the surface crackle and crack can not appear; Oil resistant, ageing-resistant, anti-solvent, corrosion-resistant and anti-oxidant, placing 30 days sizes and apparent state in general organic oil and organic solvent does not change, the spot of corrosion does not all appear in salt mist experiment, the experiment of high temperature moisture-proof and water-fast rust experiment rear surface, is the NdFeB incomparable (seeing the experimental result of enclosing) that bonds at present; Next has higher magnetic property, its remanent magnetism Br is 0.30～0.70T, and magnetic strength coercivity H b is 200～500kA/m, and HCJ Hcj is 300～800kA/m, maximum magnetic energy product (BH) max is 15～56kJ/m3, is better than all Ferrite Materials now greatly; The advantage that also has the flexible adhesion magnet at last; Apparent upper surface is smooth, bright and clean, does not fall slag; Product size scope minimum thickness can reach 0.25mm, and Breadth Maximum can reach 2000mm, and extreme length can reach 30000mm, and the minimum dimension precision reaches ± 0.05mm.
In sum, the cohesive composite permanent magnetic body that contains neodymium iron nitrogen of the present invention have the NdFeB permanent magnet incomparable cost performance, chemical property, physical property and mechanical performance, the permanent magnet apparent property of making is good, smoothly, smooth do not fall slag, can arbitrarily bend curling, the hot strength height, elongation is big, and these have determined NdFeN applicable to more wider occasions.
Description of drawings
Fig. 1 and Fig. 2: be respectively flexible neodymium iron boron and flexible neodymium iron nitrogen salt spray resistance experiment rear surface digital photograph.
Fig. 3 and Fig. 4: be respectively flexible neodymium iron boron and flexible neodymium iron nitrogen high temp moisture-proof experiment rear surface digital photograph.
Fig. 5 and Fig. 6: be respectively the water-fast rust experiment of flexible neodymium iron boron and flexible neodymium iron nitrogen rear surface digital photograph.
Embodiment
Below in conjunction with implementing experiment a kind of novel cohesive composite permanent magnetic body and manufacturing process thereof that contains neodymium iron nitrogen of the present invention further specified.
Below indicate the symbol Chinese and the abbreviation contrast that occur in the literary composition.Wherein:
Br is a residual magnetic flux density, is called for short remanent magnetism; Hcb is the magnetic strength coercive force;
Hcj is a HCJ; (BH) max is a maximum magnetic energy product;
NdFeN is a neodymium iron nitrogen; NdFeB is a neodymium iron boron;
KGs and T are the units of Br; The former is Gaussian system (CGS), kilogauss; The latter is an International System of Units (SI), tesla;
KOe and kA/m are the units of Hcb; The former is Gaussian system (CGS), kilooersted; The latter is an International System of Units (SI), kilo-ampere/rice;
KOe and kA/m are the units of Hcj; The former is Gaussian system (CGS), kilooersted; The latter is an International System of Units (SI), kilo-ampere/rice;
MGsOe and kj/m
3Be (BH)
MaxUnit; The former is Gaussian system (CGS), megagauss. Austria; The latter is an International System of Units (SI), kilo-ampere/rice
3
MPa is a hot strength unit, MPa;
SHD is a Shao Shi D hardness;
G/cm
3Be density unit, gram per centimeter
3
Embodiment 1:
Claim 10 kilograms of NdFeN magnetics, 0.06 kilogram of silane coupling agent, the coupling agent and an amount of alcohol that weigh up are evenly mixed (amount of alcohol is enough to make it to mix get final product), add the NdFeN magnetic then and in mixer, evenly mix and coat processing, deliver in the vacuum tank it dry after treating evenly.
Claim 0.68 kilogram of acrylonitrile-butadiene rubber, 0.012 kilogram of plasticising lubricant DOP0.06 kilogram, paraffin wax white, 0.006 kilogram in sulphur, vulcanization aid TMTD are 0.001 kilogram, and anti-aging agent RD is 0.021 kilogram, and the reinforcing filler white carbon is 0.03 kilogram.The NdFeN Magnaglo that above-mentioned coating is good and acrylonitrile-butadiene rubber, compounding ingredient etc. send into that (100～110 ℃) carry out mixing in the banbury, mixingly use twin-screw extruder (the roller temperature control is at 70～80 ℃) mixing again after evenly, mixingly adopt two roll calender (the roller temperature control is at 60～70 ℃) to be pressed into the thin slice of 1～3mm thickness after last slice, adopt calender (the roller temperature control is at 60～70 ℃) to build up required finished product thickness according to finished product thickness then, at last finished product is adopted hot-air cure technology to vulcanize, curing temperature is 170 ℃, and cure time is 20 minutes.Performance parameter sees Table 1 and table 2.
Table 1: magnetic property
| ?Br＝ | ??4.52 | ??kGs | ??0.452 | ???T |
| ?Hcb＝ | ??3.11 | ??kOe | ??247 | ???kA/m |
| ?Hcj＝ | ??4.71 | ??kOe | ??374 | ???kA/m |
| ?(BH) m | ??4.03 | ??MGsO | ??32.1 | ???kj/m 3 |
Table 2: physical and mechanical properties:
| Performance parameter | Unit | Characteristic value |
| Hot strength | 〔MPa〕 | ??6.5 |
| Elongation | 〔％〕 | ??150 |
| Hardness | 〔SHD〕 | ??42 |
| Density | 〔g/cm 3〕 | ?4.8 |
Embodiment 2
Claim 10 kilograms of NdFeN magnetics, 0.04 kilogram of silane coupling agent evenly mixes coupling agent and an amount of ethanol that weighs up, and adds the NdFeN magnetic then and evenly mixes in mixer and coat processing, delivers in the vacuum tank it dry after treating evenly.
Claim haloflex (CPE) 0.45 kilogram, 0.015 kilogram of plasticising lubricant DBP, 0.13 kilogram of yellow wax, anti-aging agent RD is 0.009 kilogram.The NdFeN Magnaglo that above-mentioned coating is good and haloflex, compounding ingredient etc. are sent in the banbury 100～110 ℃ and are carried out mixing, mixingly use twin-screw extruder mixing again after evenly, the roller temperature control is at 80～90 ℃, the mixing thin slice that adopts after last slice two roll calender (the roller temperature control is at 70～80 ℃) to be pressed into 1～3mm thickness adopts calender (the roller temperature control is at 70～80 ℃) to build up required finished product thickness according to finished product thickness then.
The performance parameter that finished product is surveyed sees Table 3 and table 4.
Table 3: magnetic property
| ?Br＝ | 4.59 | ??kGs | 0.45 | ??T |
| ?Hcb＝ | 3.41 | ??kOe | 271 | ??kA/m |
| ?Hcj＝ | 4.77 | ??kOe | 379 | ??kA/m |
| ?(BH) m | 4.47 | ??MGsO | 35.6 | ??kj/m 3 |
Table 4: physical and mechanical properties
| Performance parameter | Unit | Characteristic value |
| Hot strength | ?〔MPa〕 | ????6.0 |
| Elongation | ?〔％〕 | ????140 |
| Hardness | ?〔SHD〕 | ????42 |
| Density | ?〔g/cm 3〕 | ????5.2 |
Embodiment 3
Claim 5 kilograms of NdFeN magnetics, (its molecular formula is SrO6Fe to the strontium ferrite permanent magnet powder
2O
3) 3 kilograms, 0.03 kilogram of phthalate ester coupling agent evenly mixes the coupling agent and the proper amount of acetone that weigh up, adds NdFeN magnetic and strontium ferrite permanent magnet powder, evenly mixes coating processing in mixer, delivers in the vacuum tank after evenly dry.
Claim haloflex (CPE) 0.45 kilogram, 0.015 kilogram of plasticising lubricant stearic acid, 0.13 kilogram of pine tar, anti-aging agent RD is 0.009 kilogram.NdFeN magnetic that above-mentioned coating is good and strontium ferrite permanent magnet powder and haloflex, compounding ingredient etc. send into that (90～100 ℃) carry out mixing in the banbury, mixingly use twin-screw extruder (the roller temperature control is at 60～70 ℃) mixing again after evenly, the mixing thin slice that adopts after last slice two roll calender (the roller temperature control is at 50～60 ℃) to be pressed into 1～3mm thickness adopts calender (the roller temperature control is at 50～60 ℃) to build up required finished product thickness according to finished product thickness then.
The performance parameter that finished product is surveyed sees Table 5.
Table 5: magnetic property
| ?Br＝ | 3.67 | ?kGs | ?0.367 | ?T |
| ?Hcb＝ | 3.04 | ?kOe | ?239 | ?kA/m |
| ?Hcj＝ | 5.42 | ?kOe | ?434 | ?kA/m |
| ?(BH) m | 3.11 | ?MGsOe | ?24.5 | ?kj/m 3 |
Embodiment 4
Claim 1.5 kilograms of NdFeN magnetics, 13.5 kilograms of NdFeB magnetics, 0.07 kilogram of phthalate coupling agent, the coupling agent and the proper amount of acetone that weigh up are evenly mixed, add NdFeN magnetic, NdFeB magnetic then, in mixer, evenly mix coating processing, deliver in the vacuum tank it dry after treating evenly.
Claim 2.07 kilograms of natural rubbers, 0.080 kilogram of plasticising lubricant fat oil, 0.07 kilogram of industrial vaseline, 0.06 kilogram on selenium, vulcanization aid DM are 0.04 kilogram, and antioxidant SP H is 0.03 kilogram, and the reinforcing filler carbon black is 0.05 kilogram.NdFeN magnetic, NdFeB magnetic and natural rubber, the compounding ingredients etc. that above-mentioned coating is good send into that (80～90 ℃) carry out mixing in the banbury, mixingly use twin-screw extruder (the roller temperature control is at 90～100 ℃) mixing again after evenly, mixingly adopt two roll calender (the roller temperature control is at 70～80 ℃) to be pressed into the thin slice of 1～3mm thickness after last slice, adopt calender (the roller temperature control is at 70～80 ℃) to build up required finished product thickness according to finished product thickness then, at last finished product being adopted has the frame sulfuration process to vulcanize, curing temperature is 160 ℃, and cure time is 25 minutes.The end properties parameter sees Table 6.
Table 6: magnetic property
| ?Br＝ | 5.23 | ?kGs | ?0.523 | ?T |
| ?Hcb＝ | 4.14 | ?kOe | ?332 | ?kA/m |
| ?Hcj＝ | 8.99 | ?kOe | ?719 | ?kA/m |
| ?(BH) m | 5.61 | ?MGsOe | ?44.9 | ?kj/m 3 |
Embodiment 5
Claim 1.55 kilograms of NdFeN magnetics, (its molecular formula is BaO6Fe to barium ferrite permanent magnetism powder
2O
3) 13.95 kilograms, 0.09 kilogram of phthalate ester coupling agent evenly mixes coupling agent and an amount of alcohol that weighs up, and adds NdFeN magnetic and barium ferrite permanent-magnet powder, evenly mixes coating processing in mixer, delivers in the vacuum tank after evenly dry.
Claim butadiene-styrene rubber (NR) 1.2 kilograms, 0.13 kilogram of plasticising lubricant DBP, 0.05 kilogram of fat oil, 0.06 kilogram in sulphur, vulcanization aid TMTM are 0.07 kilogram, and anti-aging agent RD is 0.02 kilogram, and the reinforcing filler white carbon is 0.03 kilogram.NdFeN magnetic that above-mentioned coating is good and barium ferrite permanent-magnet powder and butadiene-styrene rubber, compounding ingredient etc. are sent in the mill (110～120 ℃) and are opened refining, use twin-screw extruder (the roller temperature control is at 90～100 ℃) mixing again after opening refining evenly, the mixing thin slice that adopts after last slice two roll calender (the roller temperature control is at 60～70 ℃) to be pressed into 1～3mm thickness adopts calender (the roller temperature control is at 60～70 ℃) to build up required finished product thickness according to finished product thickness then.At last finished product is adopted hot-air cure technology to vulcanize, curing temperature is 150 ℃, and cure time is 35 minutes.The performance parameter that finished product is surveyed sees Table 7.
Table 7: magnetic property
| ??Br＝ | 2.9 | ??kGs | ??0.29 | ??T |
| ??Hcb＝ | 2.04 | ??kOe | ??162 | ??kA/m |
| ??Hcj＝ | 2.32 | ??kOe | ??184 | ??kA/m |
| ?(BH) m | 1.93 | ??MGsO | ??15.4 | ??kj/m 3 |
Embodiment 6
Claim 3 kilograms of NdFeN magnetics, (its molecular formula is BaO6Fe to barium ferrite permanent magnetism powder
2O
3) 5 kilograms, 2 kilograms of NdFeB magnetics, 0.06 kilogram of silane coupling agent, the coupling agent and the proper amount of acetone that weigh up are evenly mixed, add NdFeN magnetic, barium ferrite permanent-magnet powder and NdFeB magnetic, in mixer, evenly mix coating processing, deliver in the vacuum tank after evenly dry.
0.30 kilogram of haloflex (CPE), 0.030 kilogram in plasticising lubricant aliphatic acid, 0.040 kilogram in macromolecule paraffin, 0.020 kilogram of DBP.NdFeN magnetic, barium ferrite, NdFeB permanent-magnet powder and haloflex, the compounding ingredients etc. that above-mentioned coating is good are sent into mill (100～110 ℃) and are opened refining, use twin-screw extruder (the roller temperature control is at 80～90 ℃) mixing again after opening refining evenly, the mixing thin slice that adopts after last slice two roll calender (the roller temperature control is at 70～80 ℃) to be pressed into 1～3mm thickness adopts calender (the roller temperature control is at 70～80 ℃) to build up required finished product thickness according to finished product thickness then.The measured performance parameter of finished product sees Table 8.
Table 8: magnetic property
| ?Br＝ | 4.27 | kGs | ?0.42 | ?T |
| ?Hcb＝ | 3.36 | kOe | ?275 | ?kA/m |
| ?Hcj＝ | 7.06 | kOe | ?561 | ?kA/m |
| ?(BH) m | 4.0 | MGsO | ?31.8 | ?kj/m 3 |
Embodiment 7:
Claim 10 kilograms of NdFeN magnetics, 0.04 kilogram of silane coupling agent, the coupling agent and an amount of alcohol that weigh up are evenly mixed (amount of alcohol is enough to make it to mix get final product), add the NdFeN magnetic then and in mixer, evenly mix and coat processing, deliver in the vacuum tank it dry after treating evenly.
Claim haloflex (CPE) 0.225 kilogram, 0.030 kilogram of plasticising lubricant stearic acid, 0.035 kilogram of macromolecule, 0.015 kilogram of DOP.The NdFeN Magnaglo that above-mentioned coating is good and haloflex, compounding ingredient etc. are sent in the mill (110～120 ℃) and are opened refining, use twin-screw extruder (the roller temperature control is at 90～100 ℃) mixing again after opening refining evenly, the mixing thin slice that adopts after last slice two roll calender (the roller temperature control is at 60～70 ℃) to be pressed into 1～3mm thickness adopts calender (the roller temperature control is at 60～70 ℃) to build up required finished product thickness according to finished product thickness then.
Performance parameter sees Table 9.
Table 9: magnetic property
| Br＝ | 4.75 | ?kGs | ?0.475 | ?T15 |
| Hcb＝ | 3.66 | ?kOe | ?291 | ?kA/m |
| Hcj＝ | 5.03 | ?kOe | ?400 | ?kA/m |
| (BH) m | 5.02 | ?MGsO | ?40.0 | ?kj/m 3 |
Experimental example:
Respectively to the permanent magnet of embodiment 3 with only utilize the flexible Nd-Fe-B permanent magnet of NdFeB magnetic powder manufacturing to experimentize.
(1) salt spray resistance experimental result:
Experiment condition: 35 ℃ of * 5%NaCl solution compartment sprayings (circulating: as to spray 1 minute, stopped 3 minutes), 96hr.
The result: digital camera is taken and is observed surface (with flexible neodymium iron boron contrast), sees Fig. 1 and Fig. 2.
As can be seen from Figure 1, behind the experiment 12hr, corrosion phenomena has appearred in flexible neodymium iron boron surface, and behind the experiment 96hr, flexible neodymium iron boron surface corrosion is serious; As can be seen from Figure 2, behind the experiment 60hr, flexible neodymium iron nitrogen begins to occur corrosion phenomena but is not obvious; Behind the experiment 96hr, there is faint corrosion phenomena on flexible neodymium iron nitrogen surface; Comparison diagram 1 and Fig. 2 can know that flexible neodymium iron nitrogen is better than flexible neodymium iron boron salt fog resistance.
(2) high temperature moisture-proof experimental result
Experiment condition: 65 ℃ of * 100%RH, 96hr.
The result: digital camera is taken and is observed surface (with flexible neodymium iron boron contrast), sees Fig. 3 and Fig. 4.
As can be seen from Figure 3, behind the experiment 24hr, corrosion phenomena has appearred in flexible neodymium iron boron surface, and behind the experiment 72hr, flexible neodymium iron boron surface corrosion is serious; As can be seen from Figure 4, behind the experiment 72hr, corrosion phenomena does not take place in flexible neodymium iron nitrogen surface substantially; Comparison diagram 3 and Fig. 4 can know that flexible neodymium iron nitrogen is better than flexible neodymium iron boron high temperature moisture-proof.
(3) water-fast rust experimental result
Experiment condition: room temperature, placed 15 days in the running water.
The result: digital camera is taken and is observed surface (with flexible neodymium iron boron contrast), sees Fig. 5 and Fig. 6.
As can be seen from Figure 5, experiment serious scale phenomenon occurred in flexible neodymium iron boron surface after 15 days; As can be seen from Figure 6, the scale reaction did not take place in flexible neodymium iron nitrogen surface after 15 days in experiment substantially; Comparison diagram 5 and Fig. 6 can know that flexible neodymium iron nitrogen is better than the water-fast rust of flexible neodymium iron boron.
More than described the preferred embodiment for the present invention, so it is not in order to limit the present invention.Those skilled in the art can not depart from the improvement and the variation of category of the present invention and spirit to embodiment disclosed herein.
Claims (10)
1, a kind of cohesive composite permanent magnetic material that contains neodymium iron nitrogen, wherein contain percentage by weight and be 85～97% permanent-magnet powder, at least containing 10% neodymium iron nitrogen in this permanent-magnet powder is permanent-magnet powder, and the compounding ingredient of 2～12% binding agent and 1～3%, described binding agent is rubber or haloflex, and compounding ingredient comprises coupling agent, reinforcing filler, age resistor and plasticising lubricant.
2, the cohesive composite permanent magnetic material that contains neodymium iron nitrogen as claimed in claim 1, wherein said permanent-magnet powder is for containing the permanent-magnet powder of 50% neodymium iron nitrogen system at least.
3, the cohesive composite permanent magnetic material that contains neodymium iron nitrogen as claimed in claim 1, wherein said 10% the permanent-magnet powder of containing at least is the neodymium iron nitrogen permanent-magnet powder that contains 100% neodymium iron nitrogen system; The composite permanet magnet powder of neodymium iron nitrogen system and ferrite system; The composite permanet magnet powder of neodymium iron nitrogen system, ferrite system and Nd-Fe-B series.
4, the cohesive composite permanent magnetic material that contains neodymium iron nitrogen as claimed in claim 2, wherein the neodymium iron nitrogen in the composite permanet magnet powder is that permanent-magnet powder is for having molecular formula NdFe
12-xM
xN
ySerial permanent-magnet powder, wherein, M is Ti, Mo or W, X=1～2, y=3～7; Ferrite is strontium ferrite or barium ferrite, and its molecular formula is respectively Sr
O6Fe
2O
3And BaO6Fe
2O
3Nd-Fe-B series permanent-magnet powder molecular formula is Nd
2(Fe
1-xM
x)
14B, wherein, M is Co, Ni, Si, Cr, Al, Mn or Ru, X=0～1.
5, the cohesive composite permanent magnetic material that contains neodymium iron nitrogen as claimed in claim 1, wherein said rubber comprise and are selected from least a in natural rubber, acrylonitrile-butadiene rubber, neoprene, silicon rubber, ethylene-propylene rubber, chlorosulfonated polyethylene, butadiene-styrene rubber, butyl rubber, polyisoamylene rubber, the fluorubber.
6, the cohesive composite permanent magnetic material that contains neodymium iron nitrogen as claimed in claim 1, wherein when binding agent was rubber, described compounding ingredient comprised coupling agent, vulcanizing agent, vulcanization aid, reinforcing filler, age resistor and plasticising lubricant; When binding agent was haloflex, compounding ingredient comprised coupling agent, age resistor, plasticising lubricant and reinforcing filler.
7, the cohesive composite permanent magnetic material that contains neodymium iron nitrogen as claimed in claim 6, wherein coupling agent is silanes or phthalandione lipid, accounts for 0.1～0.8% of total weight ratio; Vulcanizing agent is sulphur and congeners, organic peroxide or metal oxide; Vulcanization aid is selected from thiazoles, thiurams or sulfenamide, and reinforcing filler is selected from carbon black, white carbon, potter's clay, talcum powder or calcium carbonate; Age resistor is selected from amine or phenols; The plasticising lubricant is selected from mineral oils, animals and plants oils or synthetic class, its mineral oil in fluid comprises paraffin, vaseline and Petropols, animals and plants oils comprises pine tar, aliphatic acid and fat oil, the synthetic class comprises epoxy compounds, polyesters compound and chloride compounds, and these compounding ingredients except that coupling agent account for 0.9～2.2% of permanent magnet total weight ratio altogether.
8, each described preparation method who contains the cohesive composite permanent magnetic material of neodymium iron nitrogen of claim 1～7, its step comprises:
(1) be that the coupling agent of 85～97% the permanent-magnet powder that contains 10% neodymium iron nitrogen at least and 0.1～0.8% and organic solvent mix and coat processing, drying with weight ratio, this organic solvent is alcohols or ketone;
(2) will coat good permanent-magnet powder and binding agent and other compounding ingredients and send into and carry out mixing in banbury or the mill or open refining, mixing/as to open after the refining evenly, use twin-screw extruder mixing again;
(3) be pressed into thin slice, build up required finished product thickness.
9, preparation method as claimed in claim 8, wherein the mixing temperature of banbury is 80～120 ℃ in the step (2), roller temperature mixing or that open refining is 50～100 ℃.
10, preparation method as claimed in claim 9 when wherein binding agent is rubber, is being pressed into thin slice, builds up the step that required finished product thickness also comprises sulfuration afterwards, and described sulfuration can or have the frame sulfuration for hot-air cure, and curing temperature is 140～170 ℃.
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| CN1022520C (en) * | 1990-11-16 | 1993-10-20 | 北京大学 | Rareearth -Fe-N permanent magnet |
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