A kind of flexible rare-earth cementing magnet and manufacture method thereof
Technical field
The invention belongs to field of magnetic material, relate to a kind of bonding class permanent magnetic material, relate in particular to a kind of flexible rare-earth cementing magnet and manufacture method thereof.
Background technology
Along with the develop rapidly of global information industry, the IT industry of China will emerge rapidly in 10 years of future.Computer industry, auto industry and consumer electronics product market will present fierce growth to the demand of high performance magnetic material, and existing magnetic material can not satisfy the needs of high, precision and frontier product owing to self reason.
At present, the magnetic energy product (BH) of bonding class rigidity permanent magnetic material
MaxCan reach 80-160kJ/m
3Scope, but its goods are rigidity, can't strain, therefore, can't utilize this permanent magnetic material to make thin-walled, product that draw ratio is big, be difficult to satisfy the needs of high, refined, peak products in this magnetic property scope.
Extrusion molding is a kind of continuous production method, can carry out the high efficiency continuous productive process, and the equipment cost of same production capacity is cheaper than other forming method, more is imbued with flexibility, mainly can be used for producing laminar or the big magnetic product of draw ratio such as thin-walled ring-type.Can make the unrestricted substantially flexible adhesion permanent magnet product of length by the method for extrusion molding, magnet thickness can reach the ultra-thin form of 0.5mm.But, adopt the made flexible magnet of extrusion molding all to make at present by ferrite (the alignment magnetic field energy is low) or isotropic rare-earth magnetic (not adding alignment magnetic field), its magnetic property is not high, is difficult to satisfy the requirement of high, refined, peak products to magnetic property yet.In the present flexible magnet, the maximum magnetic energy product of conventional flexible adhesion ferrimagnet only is 14kJ/m
3About, the maximum magnetic energy product of the isotropism rare earth flexible adhesion magnet of up-to-date rise is also at 50kJ/m
3Below, if this magnet continues to increase by the loading that improves magnetic the performance of magnetic, need be cost just with the pliability of forfeiture magnet, cause the magnet can't moulding, the instructions for use that does not reach reality.
200410027808.5 and disclose a kind of flexible magnet and manufacture method thereof respectively in No. 200410052150.3 Chinese patent application, can obtain to have flexible preferably anisotropy magnet by in manufacture process, magnet being orientated according to these two disclosed technical schemes of patent application.But in these two disclosed technical schemes of Chinese patent application, the magnetic that is adopted is respectively single neodymium iron nitrogen magnetic and NdFeB magnetic powder, though the flexible magnet of its manufacturing has preferable flexibility, and magnetic energy product is higher, and (maximum magnetic energy product is about 96kJ/m
3), but the final molding mode that is adopted in its technical scheme is moulding in sulfurizing mould, because the restriction of vulcanizer size and sulfuration process, this molding mode can produce restriction to the size and the production efficiency of magnet, thereby can't the unrestricted substantially magnet of production length, and owing to will vulcanize, so complex manufacturing, efficient is low.
200510021891.X and disclose a kind of binding samarium-iron-nitrogen, neodymium iron nitrogen composite permanent-magnetic material and preparation method thereof respectively in No. 200510021944.8 Chinese patent application, and binding samarium-iron-nitrogen, neodymium iron nitrogen, ferrite permanent-magnet powder compound permanent-magnet material and preparation method thereof.In these two disclosed technical schemes of patent application, every product that has than high magnetic characteristics all is to adopt the die pressing manufacturing, and the form of product is a rigidity; And for anisotropic magnetic, the technical scheme of these two kinds of patent disclosures also is to adopt the manufacturing process of isotropism magnetic, do not add alignment magnetic field, the effect that this can cause bringing into play the high-performance anisotropic magnetic causes the magnetic property of magnet of the flexible form made lower.
Therefore, make a kind of high magnetic property that both possessed, the magnet of again can flexural deformation making the big L/D ratio product is one of problem demanding prompt solution in this area.
Summary of the invention
For solving the problems of the technologies described above, the object of the present invention is to provide a kind of rare-earth bond magnet, by anisotropic samarium iron nitrogen permanent magnetism powder, neodymium iron nitrogen permanent magnetism powder and NdFeB permanet magnetic powder are bondd mutually, the bonded permanent magnet that obtains has than high magnetic characteristics and good flexibility, easily flexural deformation.
The present invention also aims to provide the manufacture method of above-mentioned rare-earth bond magnet, adopt extrusion molding and in extrusion, apply high-energy orientation field, obtain to have the flexible rare-earth cementing magnet of high magnetic characteristics.
For achieving the above object, the invention provides a kind of flexible rare-earth cementing magnet, it contains percentage by weight and is: the compound permanent magnetic powder of 85%-92%, the binding agent of 6%-10% and the processing aid of 2%-5%; Wherein, this compound permanent magnetic powder comprises: anisotropic samarium iron nitrogen permanent magnetism powder, anisotropic neodymium iron nitrogen permanent magnetism powder and anisotropic NdFeB permanet magnetic powder.
Samarium iron nitrogen permanent magnetism powder of the present invention, neodymium iron nitrogen permanent magnetism powder and NdFeB permanet magnetic powder etc. all can be the anisotropic permanent magnetism powder that is purchased.The compound permanent magnetic powder that is used to make flexible rare-earth cementing magnet of the present invention can comprise that percentage by weight is respectively the anisotropic samarium iron nitrogen permanent magnetism powder of 5-90%, anisotropic neodymium iron nitrogen permanent magnetism powder and anisotropic NdFeB permanet magnetic powder.
Be the performance of the magnet that improves last acquisition, compound permanent magnetic powder of the present invention can be to handle the magnetic that forms oxide-film on the magnetic powder particle surface through surface conditioning agent.Surface conditioning agent can with magnetic generation chemical reaction, form oxide-film on magnetic powder particle surface, increase the non-oxidizability of rare-earth magnetic, increase the compatibility between magnetic and the binding agent, increase the cohesive force between the two; Surface conditioning agent of the present invention can be surface conditioning agent commonly used in this area, for example: titanate ester and silanes inorganic agent.For the rare-earth bond magnet that the present invention is made has preferable performance, preferably, when compound permanent magnetic powder is carried out surface treatment, the mixture that adopts phosphoric acid and silane coupler is as surface conditioning agent, wherein, the weight of phosphoric acid and silane coupler can be 0.4% and 0.6% of compound permanent magnetic powder weight respectively; The silanes inorganic agent can with the magnetic formation chemical bond that reacts, and phosphoric acid can make the magnetic surface form one deck passivating film, further improve the character on magnetic surface, in addition, under the effect of phosphoric acid, the irregular shape of rare-earth magnetic can improve, and becomes the granular of almost spherical by irregular sheet before handling, the flowability of magnetic when extruding can be increased like this, the mechanical property of extruding the magnetic stripe that is obtained can be improved.
In flexible rare-earth cementing magnet provided by the invention, the binding agent that is adopted is one or more in acetate-acetate ethylene copolymer, acrylonitrile-butadiene rubber, haloflex and the chlorosulfonated polyethylene etc.
In the flexible rare-earth cementing magnet of the present invention, this area various processing aids commonly used be can add, flexibilizer and age resistor etc. comprised, for example: DOP and BLE.Adding flexibilizer can improve the mechanical property of magnet, especially can improve the elongation at break of magnet; Add age resistor and can prolong useful life of magnet, prevent the magnet brittle failure of wearing out.For the bonded permanent magnet that makes manufacturing of the present invention obtains better elongation, and have long useful life, preferably, the flexibilizer that is adopted in the process of making bonded permanent magnet of the present invention adopts modified polybutadiene, and age resistor adopts RD; Modified polybutadiene is a kind of liquid of thickness, with organic substance good compatibility is arranged, can from organic substance, not separate out, can increase the flowability of binding agent, make binding agent soak into magnetic powder particle fully, avoid the inner pore that produces of magnet, also have the effect of activating agent simultaneously concurrently, improve the surface nature of filler.
The present invention also provides a kind of manufacture method of above-mentioned flexible rare-earth cementing magnet, and it may further comprise the steps:
Carry out mixing to compound permanent magnetic powder and binding agent, processing aid;
Product after mixing is carried out granulation, obtain pellet;
With the pellet extrusion molding, obtain flexible rare-earth cementing magnet by extruder;
Wherein, in the extrusion molding process, apply alignment magnetic field.
In the process of making flexible rare-earth cementing magnet of the present invention, can utilize surface conditioning agent that compound permanent magnetic powder is handled earlier, can carry out in the following ways: will be diluted to concentration with pure water by the load weighted surface conditioning agent of magnetic percentage by weight is 2% solution, pour in the blender together with magnetic then and stir, mixing time is 3-5 minute, carries out drying at last under nitrogen protection atmosphere; Processing such as mixing or operation all can be carried out according to the mode of this area routine to the permanent magnetism powder carries out.In addition, because the particle size of rare earth magnet powders is all bigger, generally at the 30-70 micron, much larger than ferritic particle size (average 1-2 micron), therefore, in extrusion molding, for reaching orientation effect preferably, the resistance that can adopt high-energy magnetic field to make rare-earth magnetic overcome binding agent rotates, and obtains anisotropic flexible rare-earth cementing magnet.
The present invention is by the combination of three kinds of rare earth permanent magnet powders such as anisotropic samarium iron nitrogen permanent magnetism powder, anisotropic neodymium iron nitrogen permanent magnetism powder and anisotropic NdFeB permanet magnetic powder, under the lower situation of composite magnetic powder powder containing quantity, obtained high performance flexible magnet, the powder containing quantity of mould pressing process is generally 98%, and the powder containing quantity of calendering technology is generally 94%; And by in the process of extrusion molding, adopting high-octane alignment magnetic field, reach the effect of orientation, make the flexible rare-earth cementing magnet of preparation have higher magnetic property and anisotropy, in use can give full play to the anisotropic properties of magnet.Simultaneously, the rare-earth bond magnet of manufacturing of the present invention also has flexible preferably, can be bent and deformed the product of making big L/D ratio; And, in the extrusion molding process,, can obtain having difform flexible rare-earth cementing magnet by selecting different moulds.
The present invention is directed to the deficiency that exists in the present bonded permanent magnet system, a kind of novel flexible rare-earth cementing magnet and manufacture method thereof are provided, samarium iron nitrogen permanent magnetism powder, neodymium iron nitrogen permanent magnetism powder and NdFeB permanet magnetic powder by adopting present high-performance anisotropic are as raw material, can solve problems of the prior art, acquisition has very high magnetic property and flexible preferably rare-earth bond magnet, widened the scope of application of flexible magnet, extended the magnetic property space of flexible magnet system, can satisfy magnetic property and the flexible requirement of high, refined, peak products magnet.
Flexible rare-earth cementing magnet provided by the invention can provide the combination of multiple machinery, physics and magnetic, for example, can directly extrude the finished product magnet by the restriction of mould, the magnet that also can extrude broad carries out the magnet that special shape is made in punching press more as requested, also can be formed directly in or be processed into the parts of overlength degree, thin wall type structure, can adopt and paste or method such as be pressed into makes up, and production technology is simple, the efficient height, with low cost.Simultaneously, magnetic field orientating extruding forming method of the present invention can be continuously produced, and the length of magnet is unrestricted, and the production efficiency height, low cost product, and this is that other flexible magnet production technologies are beyond one's reach.
Embodiment
Below in conjunction with specific embodiment flexible rare-earth cementing magnet of the present invention and manufacture method thereof are further specified, but can not be interpreted as any limitation of the invention.
According to specific embodiments of the present invention, the manufacture method of flexible rare-earth cementing magnet provided by the present invention can comprise following concrete steps:
Carry out mixing to compound permanent magnetic powder and binding agent, the processing aid that comprises anisotropic samarium iron nitrogen magnetic, anisotropic neodymium iron nitrogen magnetic and anisotropic NdFeB magnetic powder, carry out adopting when mixing 3L adding pressure type banburying machine, melting temperature is 90-100 degree centigrade, time is 15-20 minute, and pressure is 0.6-0.8MPa;
The mixing powder that obtains is rolled on two-roll calendar, the temperature of calender is 40-50 degree centigrade, obtains the sheet material that thickness is the 2.5-3.0 millimeter after the calendering, uses the pelleter pelletizing then, obtain pellet, the pellet size is being as the criterion by 6 purpose standard screens;
With the pellet extrusion molding, obtain flexible rare-earth cementing magnet by extruder;
Wherein, in the extrusion molding process, apply alignment magnetic field.
Embodiment 1
In the present embodiment, it is 5% anisotropy neodymium iron nitrogen permanent magnetism powder that the compound permanent magnetic powder that is adopted comprises percentage by weight, 45% anisotropy samarium iron nitrogen permanent magnetism powder and 50% anisotropy NdFeB permanet magnetic powder; The binding agent that is adopted is selected acetate-acetate ethylene copolymer for use, and percentage by weight is 10%, and the percentage by weight of compound permanent magnetic powder is 88%, and the percentage by weight of processing aid is 2%.
(this surface conditioning agent is phosphoric acid and silane coupler to compound permanent magnetic powder through surface conditioning agent, its weight be respectively compound permanent magnetic powder weight 0.4% and 0.6%) handle after, mixing evenly with binding agent and processing aid, broken then granulation, collect pellet by 6 purpose standard screen clothes, with the pellet that obtains by extruder extrusion molding under the effect of alignment magnetic field; Wherein the mold temperature of extruder is 160 degrees centigrade, and the extruder electric current is 3A, and rotating speed is 15rpm/min, and the size of alignment magnetic field is 1.5T.
The magnetic property of the flexible rare-earth cementing magnet that present embodiment provides is residual magnetic flux density Br=0.63T, HCJ Hcj=750KA/m, maximum magnetic energy product (BH)
MaxBe 62kJ/m
3
Embodiment 2
In the present embodiment, it is 20% anisotropy neodymium iron nitrogen magnetic that the compound permanent magnetic powder that is adopted comprises percentage by weight, 50% anisotropy samarium iron nitrogen magnetic and 30% anisotropy NdFeB magnetic powder; The binding agent that is adopted is selected the mixture of acetate-acetate ethylene copolymer and haloflex for use, and percentage by weight is 6%, and the percentage by weight of compound permanent magnetic powder is 90%, and the percentage by weight of processing aid is 4%.
(this surface conditioning agent is phosphoric acid and silane coupler to compound permanent magnetic powder through surface conditioning agent, its weight be respectively compound permanent magnetic powder weight 0.4% and 0.6%) handle after, mixing evenly with binding agent and processing aid, broken then granulation, collection can be by 6 purpose standard screen clothes pellet, with the pellet that obtains by extruder extrusion molding under the effect of alignment magnetic field; Wherein the mold temperature of extruder is 140 degrees centigrade, and the extruder electric current is 5A, and rotating speed is 15rpm/min, and the size of alignment magnetic field is 2.0T.
The magnetic property of the flexible rare-earth cementing magnet that present embodiment provides is residual magnetic flux density Br=0.75T, HCJ Hcj=752KA/m, maximum magnetic energy product (BH)
MaxBe 75kJ/m
3
Embodiment 3
In the present embodiment, it is 50% anisotropy neodymium iron nitrogen magnetic that the compound permanent magnetic powder that is adopted comprises percentage by weight, 25% anisotropy samarium iron nitrogen magnetic and 25% anisotropy NdFeB magnetic powder; The binding agent that is adopted is selected the mixture of acrylonitrile-butadiene rubber and chlorosulfonated polyethylene for use, and percentage by weight is 10%, and the percentage by weight of compound permanent magnetic powder is 85%, and the percentage by weight of processing aid is 5%.
(this surface conditioning agent is phosphoric acid and silane coupler to compound permanent magnetic powder through surface conditioning agent, its weight be respectively compound permanent magnetic powder weight 0.4% and 0.6%) handle after, mixing evenly with binding agent and processing aid, broken then granulation, collection can be by 6 purpose standard screen clothes pellet, with the pellet that obtains by extruder extrusion molding under the effect of alignment magnetic field; Wherein the mold temperature of extruder is 180 degrees centigrade, and the extruder electric current is 7A, and rotating speed is 15rpm/min, and the size of alignment magnetic field is 2.0T.
The magnetic property of the flexible rare-earth cementing magnet that present embodiment provides is residual magnetic flux density Br=0.59T, HCJ Hcj=738KA/m, maximum magnetic energy product (BH)
MaxBe 57kJ/m
3
Embodiment 4
In the present embodiment, it is 30% anisotropy neodymium iron nitrogen magnetic that the compound permanent magnetic powder that is adopted comprises percentage by weight, 30% anisotropy samarium iron nitrogen magnetic and 40% anisotropy NdFeB magnetic powder; The binding agent that is adopted is selected the mixture of acetate-acetate ethylene copolymer and acrylonitrile-butadiene rubber for use, and percentage by weight is 8%, and the percentage by weight of compound permanent magnetic powder is 89%, and the percentage by weight of processing aid is 3%.
(this surface conditioning agent is phosphoric acid and silane coupler to compound permanent magnetic powder through surface conditioning agent, its weight be respectively compound permanent magnetic powder weight 0.4% and 0.6%) handle after, mixing evenly with binding agent and processing aid, broken then granulation, collection can be by 6 purpose standard screen clothes pellet, with the pellet that obtains by extruder extrusion molding under the effect of alignment magnetic field; Wherein the mold temperature of extruder is 160 degrees centigrade, and the extruder electric current is 6A, and rotating speed is 15rpm/min, and the size of alignment magnetic field is 1.8T.
The magnetic property of the flexible rare-earth cementing magnet that present embodiment provides is residual magnetic flux density Br=0.64T, HCJ Hcj=740KA/m, maximum magnetic energy product (BH)
MaxBe 66kJ/m
3