CN116652182B - A sintering material box and method for improving the consistency of magnetic properties of rare earth permanent magnet materials - Google Patents

A sintering material box and method for improving the consistency of magnetic properties of rare earth permanent magnet materials Download PDF

Info

Publication number
CN116652182B
CN116652182B CN202310960548.XA CN202310960548A CN116652182B CN 116652182 B CN116652182 B CN 116652182B CN 202310960548 A CN202310960548 A CN 202310960548A CN 116652182 B CN116652182 B CN 116652182B
Authority
CN
China
Prior art keywords
side plate
groove
sintering
rare earth
consistency
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN202310960548.XA
Other languages
Chinese (zh)
Other versions
CN116652182A (en
Inventor
刘峰
王茹钰
郭锋
李井朋
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Baotou Yunsheng Strong Magnetic Material Co ltd
Ningbo Yunsheng Magnet Devices Technology Co Ltd
Ningbo Yunsheng Co Ltd
Original Assignee
Baotou Yunsheng Strong Magnetic Material Co ltd
Ningbo Yunsheng Magnet Devices Technology Co Ltd
Ningbo Yunsheng Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Baotou Yunsheng Strong Magnetic Material Co ltd, Ningbo Yunsheng Magnet Devices Technology Co Ltd, Ningbo Yunsheng Co Ltd filed Critical Baotou Yunsheng Strong Magnetic Material Co ltd
Priority to CN202310960548.XA priority Critical patent/CN116652182B/en
Publication of CN116652182A publication Critical patent/CN116652182A/en
Application granted granted Critical
Publication of CN116652182B publication Critical patent/CN116652182B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B22CASTING; POWDER METALLURGY
    • B22FWORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F3/00Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
    • B22F3/003Apparatus, e.g. furnaces
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B22CASTING; POWDER METALLURGY
    • B22FWORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F3/00Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
    • B22F3/10Sintering only
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B22CASTING; POWDER METALLURGY
    • B22FWORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F9/00Making metallic powder or suspensions thereof
    • B22F9/02Making metallic powder or suspensions thereof using physical processes
    • B22F9/023Hydrogen absorption
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01FMAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F1/00Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties
    • H01F1/01Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials
    • H01F1/03Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity
    • H01F1/032Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials
    • H01F1/04Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials metals or alloys
    • H01F1/047Alloys characterised by their composition
    • H01F1/053Alloys characterised by their composition containing rare earth metals
    • H01F1/055Alloys characterised by their composition containing rare earth metals and magnetic transition metals, e.g. SmCo5
    • H01F1/057Alloys characterised by their composition containing rare earth metals and magnetic transition metals, e.g. SmCo5 and IIIa elements, e.g. Nd2Fe14B
    • H01F1/0571Alloys characterised by their composition containing rare earth metals and magnetic transition metals, e.g. SmCo5 and IIIa elements, e.g. Nd2Fe14B in the form of particles, e.g. rapid quenched powders or ribbon flakes
    • H01F1/0573Alloys characterised by their composition containing rare earth metals and magnetic transition metals, e.g. SmCo5 and IIIa elements, e.g. Nd2Fe14B in the form of particles, e.g. rapid quenched powders or ribbon flakes obtained by reduction or by hydrogen decrepitation or embrittlement
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01FMAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F1/00Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties
    • H01F1/01Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials
    • H01F1/03Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity
    • H01F1/032Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials
    • H01F1/04Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials metals or alloys
    • H01F1/047Alloys characterised by their composition
    • H01F1/053Alloys characterised by their composition containing rare earth metals
    • H01F1/055Alloys characterised by their composition containing rare earth metals and magnetic transition metals, e.g. SmCo5
    • H01F1/057Alloys characterised by their composition containing rare earth metals and magnetic transition metals, e.g. SmCo5 and IIIa elements, e.g. Nd2Fe14B
    • H01F1/0571Alloys characterised by their composition containing rare earth metals and magnetic transition metals, e.g. SmCo5 and IIIa elements, e.g. Nd2Fe14B in the form of particles, e.g. rapid quenched powders or ribbon flakes
    • H01F1/0575Alloys characterised by their composition containing rare earth metals and magnetic transition metals, e.g. SmCo5 and IIIa elements, e.g. Nd2Fe14B in the form of particles, e.g. rapid quenched powders or ribbon flakes pressed, sintered or bonded together
    • H01F1/0576Alloys characterised by their composition containing rare earth metals and magnetic transition metals, e.g. SmCo5 and IIIa elements, e.g. Nd2Fe14B in the form of particles, e.g. rapid quenched powders or ribbon flakes pressed, sintered or bonded together pressed, e.g. hot working
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01FMAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F1/00Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties
    • H01F1/01Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials
    • H01F1/03Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity
    • H01F1/032Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials
    • H01F1/04Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials metals or alloys
    • H01F1/047Alloys characterised by their composition
    • H01F1/053Alloys characterised by their composition containing rare earth metals
    • H01F1/055Alloys characterised by their composition containing rare earth metals and magnetic transition metals, e.g. SmCo5
    • H01F1/057Alloys characterised by their composition containing rare earth metals and magnetic transition metals, e.g. SmCo5 and IIIa elements, e.g. Nd2Fe14B
    • H01F1/0571Alloys characterised by their composition containing rare earth metals and magnetic transition metals, e.g. SmCo5 and IIIa elements, e.g. Nd2Fe14B in the form of particles, e.g. rapid quenched powders or ribbon flakes
    • H01F1/0575Alloys characterised by their composition containing rare earth metals and magnetic transition metals, e.g. SmCo5 and IIIa elements, e.g. Nd2Fe14B in the form of particles, e.g. rapid quenched powders or ribbon flakes pressed, sintered or bonded together
    • H01F1/0577Alloys characterised by their composition containing rare earth metals and magnetic transition metals, e.g. SmCo5 and IIIa elements, e.g. Nd2Fe14B in the form of particles, e.g. rapid quenched powders or ribbon flakes pressed, sintered or bonded together sintered
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01FMAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F41/00Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties
    • H01F41/02Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties for manufacturing cores, coils, or magnets
    • H01F41/0253Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties for manufacturing cores, coils, or magnets for manufacturing permanent magnets
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01FMAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F41/00Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties
    • H01F41/02Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties for manufacturing cores, coils, or magnets
    • H01F41/0253Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties for manufacturing cores, coils, or magnets for manufacturing permanent magnets
    • H01F41/0266Moulding; Pressing

Landscapes

  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Chemical & Material Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Inorganic Chemistry (AREA)
  • Mechanical Engineering (AREA)
  • Powder Metallurgy (AREA)
  • Hard Magnetic Materials (AREA)

Abstract

本发明公开了一种提高稀土永磁材料磁性能一致性的烧结料盒及方法,包括上端开口的矩形盒体,矩形盒体通过前侧板、后侧板、左侧板、右侧板以及底板按照前后左右下的方位排布并依次连接构成,前侧板、后侧板、左侧板、右侧板以及底板之间围成矩形料腔,前侧板的上端中部设置有向下凹陷的第一凹槽,后侧板的上端中部设置有向下凹陷的第二凹槽,左侧板的上端中部设置有向下凹陷的第三凹槽,右侧板的上端中部设置有向下凹陷的第四凹槽;优点是在兼顾密闭性与排气功能,提升稀土永磁材料剩磁与内禀矫顽力的一致性的同时,制造成本低,操作步骤简单,降低了生产操作难度,不会影响烧结钕铁硼磁体生产效率,且不需要使用液体密封,不会引入其他杂质。

The invention discloses a sintering material box and a method for improving the consistency of magnetic properties of rare earth permanent magnet materials. The method comprises a rectangular box body with an upper opening, wherein the rectangular box body is formed by a front side plate, a rear side plate, a left side plate, a right side plate and a bottom plate arranged in front, back, left, right and bottom directions and connected in sequence, wherein a rectangular material cavity is surrounded by the front side plate, the rear side plate, the left side plate, the right side plate and the bottom plate, wherein a first groove which is concave downwards is arranged in the middle of the upper end of the front side plate, a second groove which is concave downwards is arranged in the middle of the upper end of the rear side plate, a third groove which is concave downwards is arranged in the middle of the upper end of the left side plate, and a fourth groove which is concave downwards is arranged in the middle of the upper end of the right side plate. The method has the advantages of taking into account both airtightness and exhaust function, improving the consistency of remanence and intrinsic coercive force of rare earth permanent magnet materials, low manufacturing cost, simple operation steps, reduced production operation difficulty, no influence on the production efficiency of sintered NdFeB magnets, no need to use liquid sealing, and no introduction of other impurities.

Description

Sintering material box and method for improving consistency of magnetic properties of rare earth permanent magnet material
Technical Field
The invention relates to a technology for improving consistency of magnetic properties of rare earth permanent magnet materials, in particular to a sintering material box and a method for improving consistency of magnetic properties of rare earth permanent magnet materials.
Background
The sintered NdFeB magnet is used as a third-generation rare earth permanent magnet material and is widely applied to equipment in the high and new technical fields of new energy automobiles, intelligent manufacturing, medical treatment, aerospace and the like due to the excellent magnetic performance. The sintered neodymium-iron-boron magnets applied to the equipment in the high and new technical field are often small-size blocks with a large number and cut by a large blank, and the consistency of the magnetic properties of each sintered neodymium-iron-boron magnet is ensured in order to ensure stable equipment performance. In terms of the development of the current industry, the consistency of magnetic performance is not solved well, and the poor consistency of magnetic performance is actually expressed in the following steps: the magnetic properties of sintered NdFeB magnets of the same brand and different batches are large, or the magnetic properties of blanks at different positions in a furnace are not small in the same batch of the furnace. Moreover, the magnetic properties of the same sintered NdFeB magnet are different from each other in different positions. Therefore, improving the consistency of the performance of sintered NdFeB products is an urgent problem to be solved by enterprises producing sintered NdFeB magnets.
In the preparation process of the sintered NdFeB magnet, a blank of the sintered NdFeB magnet needs to be protected by a material box in the sintering furnace entering process, and if nitrogen in the material box has gas exchange with outside air in the furnace entering process, the nitrogen has high probability of oxidizing a product. However, if only the tightness of the material box is considered, the release and volatilization of the gas in the deflation stage in the heating process are not timely, the shrinkage degree of the product and the compactness degree of the product are affected, the size of the sintered blank is inconsistent, and the performance of the product is greatly reduced, so that the exhaust function of the material box is also important. Therefore, it is very important to research a material box and sintering method for sintering NdFeB to consider the sealing performance and the exhaust effect of the material box.
The Chinese patent publication No. CN114054753A discloses a material box for sintering neodymium iron boron and a sintering method, wherein the material box comprises a box body and a box cover, a circle of grooves are formed in the middle of the upper end of the side wall around the box body, and a plurality of air grooves are formed in the bottoms of the grooves; the lower end of the box cover is provided with a circle of flange with a shape matched with the groove, the thickness of the flange at the position right above the air groove is smaller than the distance between the inner wall and the outer wall of the air groove, a blank is required to be put into the box during sintering, sealing liquid with a low boiling point is poured into the groove, the liquid level is positioned above the upper end face of the air groove and the bottom of the groove, the flange is aligned with the groove to cover the box cover, and the box cover is put into the sintering furnace. The material box can give consideration to the tightness and the exhaust function, the dimensional shrinkage consistency of sintered billets after sintering is good, the dimensional deviation of single products is greatly reduced, the density of the products is uniform and consistent, and the consistency of the magnetic performance (remanence and intrinsic coercivity) of sintered NdFeB magnets can be improved. However, the operation steps are complex, the operation difficulty is high, the production efficiency is affected, the sealing liquid is easy to introduce impurities, and the manufacturing cost of the box body and the box cover is high.
Disclosure of Invention
One of the technical problems to be solved by the invention is to provide a sintering material box for improving the consistency of the magnetic performance of the rare earth permanent magnet material, wherein the sintering material box has the advantages of improving the consistency of the residual magnetism and the intrinsic coercivity of the rare earth permanent magnet material while taking the tightness and the exhaust function into consideration, along with low manufacturing cost, simple operation steps, reduction of the production operation difficulty, no influence on the production efficiency of the sintered neodymium-iron-boron magnet, no need of using liquid sealing and no introduction of other impurities.
The technical scheme adopted by the invention for solving one of the technical problems is as follows: the utility model provides an improve sintering magazine of tombarthite permanent magnet material magnetism performance uniformity, includes upper end open-ended rectangle box body, rectangle box body pass through preceding curb plate, posterior lateral plate, left side board, right side board and bottom plate and arrange and connect gradually the constitution according to the position under the front and back, posterior lateral plate left side board right side board and the bottom plate between enclose into the rectangle material chamber, the upper end middle part of preceding curb plate be provided with the first recess of undercut, the upper end middle part of posterior lateral plate be provided with the second recess of undercut, the upper end middle part of left side board be provided with the third recess of undercut, the upper end middle part of right side board be provided with the fourth recess of undercut.
The cross sections of the first groove, the second groove, the third groove and the fourth groove along the vertical direction are isosceles trapezoids, and the lower bottoms of the isosceles trapezoids are positioned above the upper bottoms of the first groove, the second groove, the third groove and the fourth groove. In this structure, when a plurality of sintering magazine of range upon range of, because sintering magazine is loaded with the weight after the product is heavier, the sintering magazine of upper strata can generally be shelved earlier at next layer sintering magazine top and forward promotion again, makes upper layer sintering magazine and next layer sintering magazine align the range upon range of from top to bottom, and first recess, second recess, third recess and fourth recess are isosceles trapezoid along the cross-section of vertical direction, can avoid the last layer sintering magazine to appear blocking in the promotion in-process, and the operation is more quick and handy.
The height of the cross sections of the first groove, the second groove, the third groove and the fourth groove along the vertical direction is not more than 5mm, the difference between the bottoms and the bottoms of the cross sections of the first groove, the second groove, the third groove and the fourth groove along the vertical direction is not more than 50mm, the area of the cross section of the first groove is 1% -3% of the area of the front side surface of the rectangular material cavity, the area of the cross section of the second groove is 1% -3% of the area of the rear side surface of the rectangular material cavity, the area of the cross section of the third groove is 1% -3% of the area of the left side surface of the rectangular material cavity, and the area of the cross section of the fourth groove is 1% -3% of the area of the right side surface of the rectangular material cavity.
The bottom of bottom plate be provided with first annular groove, first annular groove's degree of depth be less than first recess second recess third recess and fourth recess's degree of depth, when a plurality of sintering magazine stacks from top to bottom, the top embedding that is located anterior board, posterior lateral plate, left side board and the right side board of the sintering magazine of next floor is located in the first annular groove that the bottom of the sintering magazine of upper strata set up.
The sintering material box for improving the consistency of the magnetic properties of the rare earth permanent magnetic materials further comprises a cover plate, a second annular groove is formed in the bottom of the cover plate, the depth of the second annular groove is smaller than that of the first groove, the second groove, the third groove and the fourth groove, and when the cover plate is arranged above the front side plate, the rear side plate, the left side plate and the right side plate, the front side plate, the rear side plate, the left side plate and the top of the right side plate can be embedded into the second annular groove.
The length of the front side plate along the left-right direction is 250-500mm, the height of the rear side plate along the up-down direction is 30-80mm, the thickness of the rear side plate along the front-back direction is 5-12mm, the length of the rear side plate along the left-right direction is equal to the length of the front side plate along the left-right direction, the height of the rear side plate along the up-down direction is equal to the height of the front side plate along the up-down direction, and the thickness of the rear side plate along the front-back direction is equal to the thickness of the front side plate along the front-back direction; the length of the left side plate along the front-back direction is 250-500mm, the height of the left side plate along the up-down direction is 30-80mm, the thickness of the right side plate along the left-right direction is 5-12mm, the length of the right side plate along the front-back direction is equal to the length of the left side plate along the front-back direction, the height of the right side plate along the up-down direction is equal to the height of the left side plate along the up-down direction, and the thickness of the right side plate along the left-right direction is equal to the thickness of the left side plate along the left-right direction.
The front side plate, the rear side plate, the left side plate, the right side plate and the bottom plate are made of graphite or carbon fiber.
Compared with the prior art, the sintering material box has the advantages that the middle part of the upper end of the front side plate of the sintering material box is provided with the first concave groove which is concave downwards, the middle part of the upper end of the rear side plate is provided with the second concave groove which is concave downwards, the middle part of the upper end of the left side plate is provided with the third concave groove which is concave downwards, the middle part of the upper end of the right side plate is provided with the fourth concave groove which is concave downwards, so that the exhaust channel of blanks during sintering is effectively increased, impurity gas is exhausted from the first concave groove, the second concave groove, the third concave groove and the fourth concave groove in the stage of massive air release of the blanks, the exhaust efficiency and the uniformity of blank exhaust at different positions are improved, the carbon content of the blanks is reduced, the consistency of the carbon content of the blanks is also improved, the consistency of the residual magnetic intrinsic coercive force of rare earth permanent magnet materials of neodymium-iron-boron materials is improved, meanwhile, the bottom plate of the sintering material box is provided with the first annular groove, the cover plate of the sintering material box is provided with a second annular groove, the depths of the first annular groove and the second annular groove are smaller than the depths of the first groove, the second groove, the third groove and the fourth groove, when a plurality of sintering material boxes are stacked up and down and the cover plate is covered on the uppermost sintering material box, the tops of the front side plate, the rear side plate, the left side plate and the right side plate of the uppermost sintering material box are embedded into the second annular groove on the cover plate, and the tops of the front side plate, the rear side plate, the left side plate and the right side plate of the next sintering material box are embedded into the first annular groove arranged at the bottom plate of the sintering material box on the upper layer in other layers of sintering material boxes, so that the blank and air can be prevented from being directly contacted in a large area in the process of entering the sintering furnace, the sealing performance is considered, therefore, the sintering material box of the invention has both the sealing performance and the exhaust function, the consistency of the remanence and intrinsic coercivity of the rare earth permanent magnet material is improved, the manufacturing cost is low, the operation steps are simple, the production operation difficulty is reduced, the production efficiency of the sintered neodymium-iron-boron magnet is not affected, liquid sealing is not needed, and other impurities are not introduced. The second technical problem to be solved by the invention is to provide a method for improving the consistency of the magnetic properties of rare earth permanent magnetic materials. According to the method, the sintering process is adjusted, so that the degassing temperature of the degassing agent is changed from the original fixed temperature to the fluctuation temperature, the degassing process of the neodymium-iron-boron blank is increased, the degassing effect is further improved, impurities are effectively removed, the consistency of the residual magnetism and the intrinsic coercivity of the rare earth permanent magnet material is further improved, meanwhile, the sintering material box is improved, the tightness and the degassing function are both considered, the consistency of the residual magnetism and the intrinsic coercivity of the rare earth permanent magnet material is improved, meanwhile, the manufacturing cost is low, the operation steps are simple, the production operation difficulty is reduced, the production efficiency of the sintered neodymium-iron-boron magnet is not affected, and the impurities are not introduced.
The second technical scheme adopted for solving the technical problems is as follows: a method for improving consistency of magnetic properties of rare earth permanent magnet materials comprises the following steps:
(1) Preparing a material according to a formula of the rare earth permanent magnet material, and obtaining a cast sheet through a rapid hardening and sheet throwing technology;
(2) Hydrogen crushing the cast sheet to obtain alloy coarse powder, and then filling the alloy coarse powder into a tank body protected by inert gas for preservation;
(3) Transferring the alloy coarse powder into an air flow grinding device for grinding to obtain fine powder with the granularity D50 of 4.0-4.5 mu m, and then filling the fine powder into a tank body protected by inert gas, wherein oxygen supplementing is carried out according to the process requirements during the grinding process of the air flow grinding device, and the online oxygen content of the air flow grinding device is kept between 0 and 50 ppm;
(4) Transferring the fine powder to a forming workshop, performing compression forming on the fine powder through a press to obtain a blank, packaging the blank with a vacuum packaging bag, and packaging with a vacuum packaging machine, wherein inert gas is always filled into the press in the compression forming process, and the oxygen content is always lower than 0.02%;
(5) The packaged blank is sent into a sintering film stripping glove box after being subjected to water isostatic pressing treatment, and the oxygen content in the sintering film stripping glove box is reduced to below 0.02 percent;
(6) In a sintering film stripping glove box, film stripping treatment is carried out on blanks, the blanks are taken out from a vacuum packaging bag and then are arranged in a sintering material box which is placed in the sintering film stripping glove box in advance, the sintering material box comprises a rectangular box body with an opening at the upper end, the rectangular box body is formed by splicing a front side plate, a rear side plate, a left side plate, a right side plate and a bottom plate according to the directions of front, rear, left and right sides, rectangular material cavities for arranging the blanks are formed between the front side plate, the rear side plate, the right side plate and the bottom plate in a surrounding manner, a first concave groove which is downwards concave is formed in the middle of the upper end of the front side plate, a second concave groove which is downwards concave is formed in the middle of the upper end of the rear side plate, a third concave groove which is downwards concave is formed in the middle of the upper end of the left side plate, and a fourth concave groove which is downwards concave is formed in the middle of the upper end of the right side plate;
(7) Under the protection of nitrogen, stacking the sintering material boxes filled with blanks up and down according to the furnace loading amount, covering a cover plate on the uppermost sintering material box, and then orderly arranging the stacked sintering material boxes in a furnace chamber of a sintering furnace for high-temperature sintering in a furnace back feeding mode, wherein the high-temperature sintering process adopts a vibration sintering process, and the specific process is as follows: heating for 20min-50min to 330-430 ℃, then repeating the cooling and heating process for 2-5 times, then continuously heating for 60min-120min to 540-650 ℃ and preserving heat for 1h-3h, then heating for 60min-120min to 780-900 ℃ and preserving heat for 1h-3h, continuously heating for 20min-50min to 900-980 ℃ and preserving heat for 1h-3h, then continuously heating for 30min-60min to 1000-1100 ℃ and preserving heat for 3h-8h, finally performing subsequent aging treatment, and discharging after the aging treatment is finished to obtain a sintered neodymium iron boron magnet, namely a rare earth permanent magnet material, wherein the cooling and heating process each time is as follows: firstly cooling for 20min-50min, wherein the cooling amplitude is 40-80 ℃, and then heating for 20min-50min to 330-430 ℃.
The cross sections of the first groove, the second groove, the third groove and the fourth groove along the vertical direction are isosceles trapezoids, and the lower bottoms of the isosceles trapezoids are positioned above the upper bottoms of the first groove, the second groove, the third groove and the fourth groove. The height of the cross sections of the first groove, the second groove, the third groove and the fourth groove along the vertical direction is not more than 5mm, the difference between the bottoms and the bottoms of the cross sections of the first groove, the second groove, the third groove and the fourth groove along the vertical direction is not more than 50mm, the area of the cross section of the first groove is 1% -3% of the area of the front side surface of the rectangular material cavity, the area of the cross section of the second groove is 1% -3% of the area of the rear side surface of the rectangular material cavity, the area of the cross section of the third groove is 1% -3% of the area of the left side surface of the rectangular material cavity, and the area of the cross section of the fourth groove is 1% -3% of the area of the right side surface of the rectangular material cavity.
Compared with the prior patent, the method has the advantages that the middle part of the upper end of the front side plate of the sintering material box is provided with the first concave groove which is downwards concave, the middle part of the upper end of the rear side plate is provided with the second concave groove which is downwards concave, the middle part of the upper end of the left side plate is provided with the third concave groove which is downwards concave, the middle part of the upper end of the right side plate is provided with the fourth concave groove which is downwards concave, thus effectively increasing the exhaust passage of blanks during sintering, and in the stage of discharging a large amount of blanks, impurity gas is discharged from the first concave groove, the second concave groove, the third concave groove and the fourth concave groove, improving the exhaust efficiency and the uniformity of blank exhaust at different positions, reducing the carbon content of the blanks and improving the consistency of the carbon content of the blanks, therefore, the consistency of residual magnetic intrinsic coercive force of the rare earth permanent magnetic material of the neodymium iron boron material is improved, meanwhile, a first annular groove is arranged at the bottom of the bottom plate of the sintering material box, a second annular groove is arranged at the cover plate of the sintering material box, the depths of the first annular groove and the second annular groove are smaller than those of the first groove, the second groove, the third groove and the fourth groove, when a plurality of sintering material boxes are stacked up and down and the cover plate is covered on the uppermost sintering material box, the tops of the front side plate, the rear side plate, the left side plate and the right side plate of the uppermost sintering material box are embedded into the second annular groove on the cover plate, and in other layers of sintering material boxes, the front side plate, the third groove and the fourth groove of the sintering material box on the next layer are embedded into the second annular groove, The tops of the rear side plate, the left side plate and the right side plate are embedded into a first annular groove arranged at the bottom of the bottom plate of the sintering material box at the upper layer, so that blanks can be prevented from being in direct contact with air in a large area in the process of entering a sintering furnace, tightness is considered, the stacked sintering material boxes are fed into the furnace after the sintering (the mode of feeding the furnace after the furnace refers to that a film stripping glove box is connected with a sintering furnace back door, the sintering furnace back door is opened, the stacked sintering material boxes in the film stripping glove box are transferred into the sintering furnace under the nitrogen protection atmosphere), and the stacked sintering material boxes are orderly arranged in the furnace chamber of the sintering furnace to be sintered at high temperature, so that the blanks are prevented from contacting with the air, and the blanks are prevented from being oxidized; In addition, the sintered NdFeB magnet is added with an antioxidant, a lubricant and other additives which ensure that powder is not oxidized and help the powder to be ground by air flow grinding, the additives such as the lubricant, a release agent and the like are also used for improving the powder formability in the stirring and forming stages, the orientation degree of powder particles in a magnetic field is improved, the types of the existing additives are various, the use of the powder modification additive can improve the performance of the sintered NdFeB magnet, so the addition amount of the powder modification additive in the industry is gradually increased, but the additives are a multi-component organic compound, a large amount of C element and O element are introduced, the performance of the NdFeB permanent magnet material is affected if the excessive C element and O element are not discharged in time, Therefore, the invention further improves the sintering process into a vibration sintering process, and specifically: heating for 20min-50min to 330-430 ℃, then repeating the cooling and heating process for 2-5 times, then continuously heating for 60min-120min to 540-650 ℃ and preserving heat for 1h-3h, then continuously heating for 60min-120min to 780-900 ℃ and preserving heat for 1h-3h, continuously heating for 20min-50min to 900-980 ℃ and preserving heat for 1h-3h, then continuously heating for 30min-60min to 1000-1100 ℃ and preserving heat for 3h-8h, Finally, carrying out subsequent aging treatment, and discharging after the aging treatment is finished to obtain a sintered neodymium-iron-boron magnet, namely a rare earth permanent magnet material, wherein the temperature reducing and then increasing process each time is as follows: firstly cooling for 20min-50min, wherein the cooling amplitude is 40-80 ℃, then heating for 20min-50min to 330-430 ℃, discharging C and O (wherein the temperature stage of 330-430 ℃ is the optimal temperature interval for discharging C and O) through the alternation of heating and cooling in the vibration sintering process, thereby changing the degassing temperature of the degassing agent from the original fixed temperature to the fluctuation temperature through adjusting the sintering process, increasing the degassing process of the neodymium iron boron green body, The method further improves the stripping effect, effectively eliminates impurities, improves the consistency of residual magnetism and intrinsic coercivity of the rare earth permanent magnet material, combines the improved sintering material box, ensures that the sealing performance and the exhaust function are both considered, improves the consistency of residual magnetism and intrinsic coercivity of the rare earth permanent magnet material, and has the advantages of low manufacturing cost, simple operation steps, reduced production and operation difficulty, no influence on the production efficiency of the sintered neodymium-iron-boron magnet and no impurity introduction.
Drawings
FIG. 1 is a schematic diagram of a sintering material box for improving consistency of magnetic properties of rare earth permanent magnet materials;
FIG. 2 is a schematic diagram II of a sintering material box for improving the consistency of magnetic properties of rare earth permanent magnet materials;
FIG. 3 is a front view of a sintering magazine for improving consistency of magnetic properties of rare earth permanent magnet materials according to the present invention;
FIG. 4 is a left side view of the sintering material box for improving the consistency of the magnetic properties of the rare earth permanent magnet material;
fig. 5 is a top view of the sintering material box for improving the consistency of the magnetic properties of the rare earth permanent magnet material.
Detailed Description
The invention discloses a sintering material box for improving consistency of magnetic properties of rare earth permanent magnet materials, and the sintering material box is further described in detail below with reference to the embodiment of the drawings.
Embodiment one: as shown in fig. 1 to 5, a sintering magazine for improving the consistency of magnetic properties of rare earth permanent magnet materials comprises a rectangular box body with an opening at the upper end, wherein the rectangular box body is formed by arranging and sequentially connecting a front side plate 1, a rear side plate 2, a left side plate 3, a right side plate 4 and a bottom plate 5 according to the front-back left-right lower directions, a rectangular material cavity 6 is formed by encircling between the front side plate 1, the rear side plate 2, the left side plate 3, the right side plate 4 and the bottom plate 5, a first concave groove 7 which is concave downwards is arranged in the middle of the upper end of the front side plate 1, a second concave groove 8 which is concave downwards is arranged in the middle of the upper end of the rear side plate 2, a third concave groove 9 which is concave downwards is arranged in the middle of the upper end of the left side plate 3, and a fourth concave downwards is arranged in the middle of the upper end of the right side plate 4.
In this embodiment, the front side plate 1, the rear side plate 2, the left side plate 3, the right side plate 4 and the bottom plate 5 are made of graphite.
Embodiment two: this embodiment is substantially the same as embodiment one, except that: in this embodiment, the cross sections of the first groove 7, the second groove 8, the third groove 9 and the fourth groove 10 along the vertical direction are isosceles trapezoids, and the lower bottoms of the isosceles trapezoids are located above the upper bottoms thereof.
In this embodiment, the heights of the cross sections of the first groove 7, the second groove 8, the third groove 9 and the fourth groove 10 along the vertical direction are 3mm, the difference between the bottoms and the bottoms of the cross sections of the first groove 7, the second groove 8, the third groove 9 and the fourth groove 10 along the vertical direction is 50mm, the area of the cross section of the first groove 7 is 1% of the front side surface area of the rectangular material cavity 6, the area of the cross section of the second groove 8 is 1% of the rear side surface area of the rectangular material cavity 6, the area of the cross section of the third groove 9 is 1% of the left side surface area of the rectangular material cavity 6, and the area of the cross section of the fourth groove 10 is 1% of the right side surface area of the rectangular material cavity 6.
In this embodiment, the bottom of the bottom plate 5 is provided with a first annular groove 11, the depth of the first annular groove 11 is smaller than the depths of the first groove 7, the second groove 8, the third groove 9 and the fourth groove 10, and when a plurality of sintering cartridges are stacked up and down, the top of the front side plate 1, the rear side plate 2, the left side plate 3 and the right side plate 4 of the sintering cartridge located in the next layer is embedded into the first annular groove 11 provided at the bottom of the sintering cartridge located in the previous layer.
In this embodiment, a sintering magazine for improving consistency of magnetic properties of rare earth permanent magnetic materials further includes a cover plate 12, a second annular groove 13 is provided at the bottom of the cover plate 12, the depth of the second annular groove 13 is smaller than the depth of the first groove 7, the second groove 8, the third groove 9 and the fourth groove 10, and when the cover plate 12 is disposed above the front side plate 1, the rear side plate 2, the left side plate 3 and the right side plate 4, the top of the front side plate 1, the rear side plate 2, the left side plate 3 and the right side plate 4 can be embedded into the second annular groove 13, and the cover plate 12 is made of graphite.
In the present embodiment, the length of the front side plate 1 in the left-right direction is 500mm, the height in the up-down direction is 80mm, the thickness in the front-back direction is 5mm, the length of the rear side plate 2 in the left-right direction is equal to the length of the front side plate 1 in the left-right direction, the height of the rear side plate 2 in the up-down direction is equal to the height of the front side plate 1 in the up-down direction, and the thickness of the rear side plate 2 in the front-back direction is equal to the thickness of the front side plate 1 in the front-back direction; the length of the left side plate 3 in the front-rear direction is 300mm, the height in the up-down direction is 80mm, the thickness in the left-right direction is 5mm, the length of the right side plate 4 in the front-rear direction is equal to the length of the left side plate 3 in the front-rear direction, the height of the right side plate 4 in the up-down direction is equal to the height of the left side plate 3 in the up-down direction, and the thickness of the right side plate 4 in the left-right direction is equal to the thickness of the left side plate 3 in the left-right direction.
Embodiment III: this embodiment is substantially the same as embodiment one, except that: in this embodiment, the cross sections of the first groove 7, the second groove 8, the third groove 9 and the fourth groove 10 along the vertical direction are isosceles trapezoids, and the lower bottoms of the isosceles trapezoids are located above the upper bottoms thereof.
In this embodiment, the height of the cross sections of the first groove 7, the second groove 8, the third groove 9 and the fourth groove 10 in the vertical direction is 5mm, the difference between the bottom and the upper bottom of the cross sections of the first groove 7, the second groove 8, the third groove 9 and the fourth groove 10 in the vertical direction is 50mm, the area of the cross section of the first groove 7 is 3% of the front side area of the rectangular material cavity 6, the area of the cross section of the second groove 8 is 3% of the rear side area of the rectangular material cavity 6, the area of the cross section of the third groove 9 is 3% of the left side area of the rectangular material cavity 6, and the area of the cross section of the fourth groove 10 is 3% of the right side area of the rectangular material cavity 6.
In this embodiment, the bottom of the bottom plate 5 is provided with a first annular groove 11, the depth of the first annular groove 11 is smaller than the depths of the first groove 7, the second groove 8, the third groove 9 and the fourth groove 10, and when a plurality of sintering cartridges are stacked up and down, the top of the front side plate 1, the rear side plate 2, the left side plate 3 and the right side plate 4 of the sintering cartridge located in the next layer is embedded into the first annular groove 11 provided at the bottom of the sintering cartridge located in the previous layer.
In this embodiment, a sintering magazine for improving consistency of magnetic properties of rare earth permanent magnetic materials further includes a cover plate 12, a second annular groove 13 is provided at the bottom of the cover plate 12, the depth of the second annular groove 13 is smaller than the depth of the first groove 7, the second groove 8, the third groove 9 and the fourth groove 10, and when the cover plate 12 is disposed above the front side plate 1, the rear side plate 2, the left side plate 3 and the right side plate 4, the top of the front side plate 1, the rear side plate 2, the left side plate 3 and the right side plate 4 can be embedded into the second annular groove 13, and the cover plate 12 is made of graphite.
In the present embodiment, the length of the front side plate 1 in the left-right direction is 500mm, the height in the up-down direction is 80mm, the thickness in the front-back direction is 5mm, the length of the rear side plate 2 in the left-right direction is equal to the length of the front side plate 1 in the left-right direction, the height of the rear side plate 2 in the up-down direction is equal to the height of the front side plate 1 in the up-down direction, and the thickness of the rear side plate 2 in the front-back direction is equal to the thickness of the front side plate 1 in the front-back direction; the length of the left side plate 3 in the front-rear direction is 300mm, the height in the up-down direction is 80mm, the thickness in the left-right direction is 5mm, the length of the right side plate 4 in the front-rear direction is equal to the length of the left side plate 3 in the front-rear direction, the height of the right side plate 4 in the up-down direction is equal to the height of the left side plate 3 in the up-down direction, and the thickness of the right side plate 4 in the left-right direction is equal to the thickness of the left side plate 3 in the left-right direction.
The invention also discloses a method for improving the consistency of the magnetic properties of the rare earth permanent magnet material, and the method is further described in detail below with reference to the embodiment of the drawings.
Embodiment four: a method for improving consistency of magnetic properties of rare earth permanent magnet materials comprises the following steps:
(1) Preparing materials according to the formula of a 42SH brand neodymium-iron-boron magnet, and obtaining cast sheets through a rapid hardening and sheet throwing technology;
(2) Hydrogen crushing the cast sheet to obtain alloy coarse powder, and then filling the alloy coarse powder into a tank body protected by inert gas for preservation;
(3) Transferring the alloy coarse powder into an air flow grinding device for grinding to obtain fine powder with the granularity D50 of 4.0-4.5 mu m, and then filling the fine powder into a tank body protected by inert gas, wherein oxygen supplementing is carried out according to the process requirements during the grinding process of the air flow grinding device, and the online oxygen content of the air flow grinding device is kept between 0 and 50 ppm;
(4) Transferring the fine powder to a forming workshop, performing compression forming on the fine powder through a press to obtain a blank, packaging the blank with a vacuum packaging bag, and packaging with a vacuum packaging machine, wherein inert gas is always filled into the press in the compression forming process, and the oxygen content is always lower than 0.02%;
(5) The packaged blank is sent into a sintering film stripping glove box after being subjected to water isostatic pressing treatment, and the oxygen content in the sintering film stripping glove box is reduced to below 0.02 percent;
(6) In a sintering film peeling glove box, film peeling treatment is carried out on blanks, the blanks are taken out from a vacuum packaging bag and then are arranged in a sintering material box which is placed in the sintering film peeling glove box in advance, as shown in fig. 1 to 5, the sintering material box comprises a rectangular box body with an opening at the upper end, the rectangular box body is formed by splicing a front side plate 1, a rear side plate 2, a left side plate 3, a right side plate 4 and a bottom plate 5 according to the directions of front, rear, left and right sides, the front side plate 1, the rear side plate 2, the left side plate 3, the right side plate 4 and the bottom plate 5, a rectangular material cavity 6 for arranging the blanks is enclosed between the front side plate 1, the rear side plate 2, the left side plate 3, the right side plate 4 and the bottom plate 5, a first concave groove 7 which is downwards concave is arranged at the middle part of the upper end of the front side plate 1, a second concave groove 8 which is downwards concave is arranged at the middle part of the upper end of the rear side plate 2, a third concave groove 9 which is downwards concave is arranged at the middle part of the upper end of the left side plate 3, and a fourth concave groove 10 which is downwards concave is arranged at the middle part of the upper end of the right side plate 4; the front side plate 1, the rear side plate 2, the left side plate 3, the right side plate 4 and the bottom plate 5 are made of graphite;
(7) Under the protection of nitrogen, stacking the sintering material boxes filled with blanks up and down according to the furnace loading amount, covering a cover plate 12 on the uppermost sintering material box, wherein the cover plate 12 is made of graphite, and then arranging the stacked sintering material boxes in a furnace chamber of a sintering furnace in sequence by adopting a furnace-after-furnace feeding mode for high-temperature sintering, wherein the high-temperature sintering process adopts a vibration sintering process, and the specific process is as follows: heating for 30min to 430 ℃, repeating the cooling and heating process for 3 times, continuously heating for 90min to 600 ℃ and preserving heat for 1h, heating for 90min to 850 ℃ and preserving heat for 1h, continuously heating for 40min to 960 ℃ and preserving heat for 1.5h, then heating for 30min to 1060 ℃ and preserving heat for 4h, finally performing subsequent aging treatment, and discharging after the aging treatment is finished to obtain a sintered neodymium-iron-boron magnet, namely a rare earth permanent magnet material, wherein the cooling and heating process for each time is as follows: firstly cooling for 30min to 350 ℃, and then heating for 30min to 430 ℃.
In this embodiment, the cross sections of the first groove 7, the second groove 8, the third groove 9 and the fourth groove 10 along the vertical direction are isosceles trapezoids, and the lower bottoms of the isosceles trapezoids are located above the upper bottoms thereof.
In this embodiment, the height of the cross sections of the first groove 7, the second groove 8, the third groove 9 and the fourth groove 10 in the vertical direction is 3mm, the difference between the bottom and the upper bottom of the cross sections of the first groove 7, the second groove 8, the third groove 9 and the fourth groove 10 in the vertical direction is 50mm, the area of the cross section of the first groove 7 is 1% of the front side area of the rectangular cavity 6, the area of the cross section of the second groove 8 is 1% of the rear side area of the rectangular cavity 6, the area of the cross section of the third groove 9 is 1% of the left side area of the rectangular cavity 6, and the area of the cross section of the fourth groove 10 is 1% of the right side area of the rectangular cavity 6.
In this embodiment, the bottom of the bottom plate 5 is provided with a first annular groove 11, the depth of the first annular groove 11 is smaller than the depths of the first groove 7, the second groove 8, the third groove 9 and the fourth groove 10, and when a plurality of sintering cartridges are stacked up and down, the top of the front side plate 1, the rear side plate 2, the left side plate 3 and the right side plate 4 of the sintering cartridge located in the next layer is embedded into the first annular groove 11 provided at the bottom of the sintering cartridge located in the previous layer.
In this embodiment, the bottom of the cover plate 12 is provided with the second annular groove 13, the depth of the second annular groove 13 is smaller than the depths of the first groove 7, the second groove 8, the third groove 9 and the fourth groove 10, and when the cover plate 12 is disposed above the front side plate 1, the rear side plate 2, the left side plate 3 and the right side plate 4, the tops of the front side plate 1, the rear side plate 2, the left side plate 3 and the right side plate 4 can be embedded into the second annular groove 13.
In the present embodiment, the length of the front side plate 1 in the left-right direction is 500mm, the height in the up-down direction is 80mm, the thickness in the front-back direction is 5mm, the length of the rear side plate 2 in the left-right direction is equal to the length of the front side plate 1 in the left-right direction, the height of the rear side plate 2 in the up-down direction is equal to the height of the front side plate 1 in the up-down direction, and the thickness of the rear side plate 2 in the front-back direction is equal to the thickness of the front side plate 1 in the front-back direction; the length of the left side plate 3 in the front-rear direction is 300mm, the height in the up-down direction is 80mm, the thickness in the left-right direction is 5mm, the length of the right side plate 4 in the front-rear direction is equal to the length of the left side plate 3 in the front-rear direction, the height of the right side plate 4 in the up-down direction is equal to the height of the left side plate 3 in the up-down direction, and the thickness of the right side plate 4 in the left-right direction is equal to the thickness of the left side plate 3 in the left-right direction.
In this embodiment, during the high temperature sintering process, various impurity gases in the blank can be more rapidly and uniformly discharged through the first groove 7, the second groove 8, the third groove 9, and the fourth groove 10 in the sintering magazine. 8 sintered NdFeB magnets were selected at random positions after being discharged from the furnace and used as samples for testing magnetic properties and carbon content, and specific data are shown in Table 1.
Comparative example one: the present comparative example uses a conventional sintering process, and the sintering cartridge of example four is not used, but a conventional cartridge is used, and the other processes are the same as example four. 8 sintered NdFeB magnets of comparative example I were selected at random positions after tapping and used as samples for testing magnetic properties and carbon content, and specific data are shown in Table 2.
Table 1: example four sample magnetic Properties
Table 2: comparative example one sample magnetic Properties
As can be seen from an analysis of the data in tables 1 and 2: the sample four of example had a maximum remanence of 13.39 kGs, a minimum remanence of 13.31 kGs, a difference (. DELTA.B r) of 0.08 kGs, a maximum intrinsic coercivity H cJ of 20.60 kOe, a minimum H cJ of 20.24 kOe, and a difference (. DELTA.H cJ) of 0.36kOe. The sample of comparative example one had a maximum remanence of 13.37 kGs, a minimum remanence of 13.12 kGs, a difference (. DELTA.B r) of 0.25kGs, a maximum intrinsic coercivity H cJ of 20.54 kOe, a minimum H cJ of 19.82kOe, and a difference (. DELTA.H cJ) of 0.72kOe. Therefore, the blank residual magnetism and coercive force consistency of the fourth embodiment are improved, the carbon content is lower, the carbon content consistency is also obviously improved, and the consistency of the magnetic performance of the sintered NdFeB magnet is generally improved.
Fifth embodiment: a method for improving consistency of magnetic properties of rare earth permanent magnet materials comprises the following steps:
(1) Preparing materials according to the formula of a 45SH brand neodymium-iron-boron magnet, and obtaining cast sheets through a rapid hardening and sheet throwing technology;
(2) Hydrogen crushing the cast sheet to obtain alloy coarse powder, and then filling the alloy coarse powder into a tank body protected by inert gas for preservation;
(3) Transferring the alloy coarse powder into an air flow grinding device for grinding to obtain fine powder with the granularity D50 of 4.0-4.5 mu m, and then filling the fine powder into a tank body protected by inert gas, wherein oxygen supplementing is carried out according to the process requirements during the grinding process of the air flow grinding device, and the online oxygen content of the air flow grinding device is kept between 0 and 50 ppm;
(4) Transferring the fine powder to a forming workshop, performing compression forming on the fine powder through a press to obtain a blank, packaging the blank with a vacuum packaging bag, and packaging with a vacuum packaging machine, wherein inert gas is always filled into the press in the compression forming process, and the oxygen content is always lower than 0.02%;
(5) The packaged blank is sent into a sintering film stripping glove box after being subjected to water isostatic pressing treatment, and the oxygen content in the sintering film stripping glove box is reduced to below 0.02 percent;
(6) In a sintering film peeling glove box, film peeling treatment is carried out on blanks, the blanks are taken out from a vacuum packaging bag and then are arranged in a sintering material box which is placed in the sintering film peeling glove box in advance, as shown in fig. 1 to 5, the sintering material box comprises a rectangular box body with an opening at the upper end, the rectangular box body is formed by splicing a front side plate 1, a rear side plate 2, a left side plate 3, a right side plate 4 and a bottom plate 5 according to the directions of front, rear, left and right sides, the front side plate 1, the rear side plate 2, the left side plate 3, the right side plate 4 and the bottom plate 5, a rectangular material cavity 6 for arranging the blanks is enclosed between the front side plate 1, the rear side plate 2, the left side plate 3, the right side plate 4 and the bottom plate 5, a first concave groove 7 which is downwards concave is arranged at the middle part of the upper end of the front side plate 1, a second concave groove 8 which is downwards concave is arranged at the middle part of the upper end of the rear side plate 2, a third concave groove 9 which is downwards concave is arranged at the middle part of the upper end of the left side plate 3, and a fourth concave groove 10 which is downwards concave is arranged at the middle part of the upper end of the right side plate 4;
(7) Under the protection of nitrogen, stacking the sintering material boxes filled with blanks up and down according to the furnace loading amount, covering a cover plate 12 on the uppermost sintering material box, wherein the cover plate 12 is made of graphite, and then arranging the stacked sintering material boxes in a furnace chamber of a sintering furnace in sequence by adopting a furnace-after-furnace feeding mode for high-temperature sintering, wherein the high-temperature sintering process adopts a vibration sintering process, and the specific process is as follows: heating for 30min to 430 ℃, repeating the cooling and heating process for 3 times, continuously heating for 90min to 600 ℃ and preserving heat for 1h, heating for 90min to 850 ℃ and preserving heat for 2h, continuously heating for 40min to 960 ℃ and preserving heat for 1.5h, then heating for 30min to 1060 ℃ and preserving heat for 4h, finally performing subsequent aging treatment, and discharging after the aging treatment is finished to obtain a sintered neodymium-iron-boron magnet, namely a rare earth permanent magnet material, wherein the cooling and heating process for each time is as follows: firstly cooling for 30min to 350 ℃, and then heating for 30min to 430 ℃.
In this embodiment, the cross sections of the first groove 7, the second groove 8, the third groove 9 and the fourth groove 10 along the vertical direction are isosceles trapezoids, and the lower bottoms of the isosceles trapezoids are located above the upper bottoms thereof.
In this embodiment, the height of the cross sections of the first groove 7, the second groove 8, the third groove 9 and the fourth groove 10 in the vertical direction is 3mm, the difference between the bottom and the upper bottom of the cross sections of the first groove 7, the second groove 8, the third groove 9 and the fourth groove 10 in the vertical direction is 50mm, the area of the cross section of the first groove 7 is 1% of the front side area of the rectangular cavity 6, the area of the cross section of the second groove 8 is 1% of the rear side area of the rectangular cavity 6, the area of the cross section of the third groove 9 is 1% of the left side area of the rectangular cavity 6, and the area of the cross section of the fourth groove 10 is 1% of the right side area of the rectangular cavity 6.
In this embodiment, the bottom of the bottom plate 5 is provided with a first annular groove 11, the depth of the first annular groove 11 is smaller than the depths of the first groove 7, the second groove 8, the third groove 9 and the fourth groove 10, and when a plurality of sintering cartridges are stacked up and down, the top of the front side plate 1, the rear side plate 2, the left side plate 3 and the right side plate 4 of the sintering cartridge located in the next layer is embedded into the first annular groove 11 provided at the bottom of the sintering cartridge located in the previous layer.
In this embodiment, the bottom of the cover plate 12 is provided with the second annular groove 13, the depth of the second annular groove 13 is smaller than the depths of the first groove 7, the second groove 8, the third groove 9 and the fourth groove 10, and when the cover plate 12 is disposed above the front side plate 1, the rear side plate 2, the left side plate 3 and the right side plate 4, the tops of the front side plate 1, the rear side plate 2, the left side plate 3 and the right side plate 4 can be embedded into the second annular groove 13.
In the present embodiment, the length of the front side plate 1 in the left-right direction is 500mm, the height in the up-down direction is 80mm, the thickness in the front-back direction is 5mm, the length of the rear side plate 2 in the left-right direction is equal to the length of the front side plate 1 in the left-right direction, the height of the rear side plate 2 in the up-down direction is equal to the height of the front side plate 1 in the up-down direction, and the thickness of the rear side plate 2 in the front-back direction is equal to the thickness of the front side plate 1 in the front-back direction; the length of the left side plate 3 in the front-rear direction is 300mm, the height in the up-down direction is 80mm, the thickness in the left-right direction is 5mm, the length of the right side plate 4 in the front-rear direction is equal to the length of the left side plate 3 in the front-rear direction, the height of the right side plate 4 in the up-down direction is equal to the height of the left side plate 3 in the up-down direction, and the thickness of the right side plate 4 in the left-right direction is equal to the thickness of the left side plate 3 in the left-right direction.
In this embodiment, during the high temperature sintering process, various impurity gases in the blank can be more rapidly and uniformly discharged through the first groove 7, the second groove 8, the third groove 9, and the fourth groove 10 in the sintering magazine. 8 sintered NdFeB magnets were selected at random positions after being discharged from the furnace and used as samples for testing magnetic properties and carbon content, and specific data are shown in Table 3.
Comparative example two: the sintering magazine of example five was used in this comparative example, but a conventional sintering process was employed. 8 sintered NdFeB magnets of comparative example II were selected at random positions after being discharged from the furnace and used as samples for testing magnetic properties and carbon content, and specific data are shown in Table 4.
Table 3: example five sample magnetic Properties
Table 4: comparative example two sample magnetic Properties
From the data in tables 3 and 4, the maximum value of the residual magnetism of the sample in example five was 13.65kGs, the minimum value of the residual magnetism was 13.51kGs, and the difference (. DELTA.B r) was 0.14kGs. The intrinsic coercivity H cJ was a maximum of 21.95kOe, the H cJ minimum of 21.62kOe, and the difference (. DELTA.H cJ) was 0.33kOe. The sample of comparative example two had a maximum remanence of 13.61kGs, a minimum remanence of 13.40kGs and a difference (Δb r) of 0.21kGs. The maximum value of the intrinsic coercive force H cJ is 22.27kOe, the minimum value of H cJ is 21.39kOe, the difference (delta H cJ) is 0.88kOe, and at the moment, the oxygen content of the sample is generally increased, and the sample is easily oxidized, so that the magnetic performance is reduced. Therefore, the sintering process is combined with the proper range of the heights of the cross sections of the first groove 7, the second groove 8, the third groove 9 and the fourth groove 10 along the vertical direction, so that the consistency of the residual magnetism and the coercive force of the sintered NdFeB magnet can be improved, the carbon content is lower, the consistency of the carbon content is obviously improved, and the consistency of the magnetic performance of the sintered NdFeB magnet is generally improved.

Claims (3)

1.一种提高稀土永磁材料磁性能一致性的方法,其特征在于包括以下步骤:1. A method for improving the consistency of magnetic properties of rare earth permanent magnet materials, characterized by comprising the following steps: (1)根据稀土永磁材料的配方准备材料,然后通过速凝甩片技术得到铸片;(1) Prepare the material according to the formula of rare earth permanent magnet material, and then obtain the casting sheet by rapid solidification and sheet throwing technology; (2)将铸片氢碎得到合金粗粉,然后将合金粗粉装入有惰性气体保护的罐体中进行保存;(2) crushing the cast sheet by hydrogen to obtain alloy coarse powder, and then storing the alloy coarse powder in a tank protected by inert gas; (3)将合金粗粉流转至气流磨设备中进行磨粉,得到粒度D50为4.0μm-4.5μm的细粉,然后将细粉装入有惰性气体保护的罐体中,其中,在气流磨设备磨粉的过程中,根据工艺要求进行补氧,气流磨设备在线氧含量保持在0-50ppm之间;(3) The alloy coarse powder is transferred to a jet mill for grinding to obtain fine powder with a particle size D50 of 4.0 μm-4.5 μm, and then the fine powder is loaded into a tank protected by inert gas. During the grinding process of the jet mill, oxygen is supplemented according to the process requirements, and the online oxygen content of the jet mill is maintained between 0 and 50 ppm; (4)将细粉流转至成型车间,通过压机对细粉进行压制成型,得到坯料,然后将压坯用真空包装袋包装,并用真空包装机封装,其中,在压制成型过程中,所述的压机内部一直充入惰性气体,保持氧含量一直低于0.02%;(4) The fine powder is transferred to a molding workshop, and the fine powder is pressed and molded by a press to obtain a blank, and then the blank is packaged in a vacuum packaging bag and sealed by a vacuum packaging machine, wherein during the pressing and molding process, the press is always filled with an inert gas to keep the oxygen content below 0.02%; (5)将封装后的坯料经过水等静压处理后送入烧结剥膜手套箱中,将烧结剥膜手套箱中的氧含量降至0.02%以下;(5) After water isostatic pressing, the encapsulated blank is sent into a sintering and stripping glove box, and the oxygen content in the sintering and stripping glove box is reduced to below 0.02%; (6)在烧结剥膜手套箱中,对坯料进行剥膜处理,将坯料从真空包装袋中取出后排布在预先放置在烧结剥膜手套箱中的烧结料盒中,所述的烧结料盒包括上端开口的矩形盒体,所述的矩形盒体通过前侧板、后侧板、左侧板、右侧板以及底板按照前后左右下的方位拼接构成,所述的前侧板、所述的后侧板、所述的左侧板、所述的右侧板以及所述的底板之间围成用于排布坯料的矩形料腔,所述的前侧板的上端中部设置有向下凹陷的第一凹槽,所述的后侧板的上端中部设置有向下凹陷的第二凹槽,所述的左侧板的上端中部设置有向下凹陷的第三凹槽,所述的右侧板的上端中部设置有向下凹陷的第四凹槽;(6) In the sintering and stripping glove box, the blank is stripped, and the blank is taken out of the vacuum packaging bag and arranged in a sintering material box pre-placed in the sintering and stripping glove box, the sintering material box comprising a rectangular box body with an upper end opening, the rectangular box body being formed by splicing a front side plate, a rear side plate, a left side plate, a right side plate and a bottom plate in front, back, left, right and bottom directions, the front side plate, the rear side plate, the left side plate, the right side plate and the bottom plate forming a rectangular material cavity for arranging the blank, the front side plate having a first groove sunken downwardly in the middle of the upper end, the rear side plate having a second groove sunken downwardly in the middle of the upper end, the left side plate having a third groove sunken downwardly in the middle of the upper end, and the right side plate having a fourth groove sunken downwardly in the middle of the upper end; (7)在氮气保护氛围下,根据装炉量先将装满坯料的烧结料盒上下层叠,并在最上层烧结料盒上盖上一盖板,然后将层叠的烧结料盒采用炉后进炉的方式,按序排列在烧结炉炉腔内进行高温烧结,其中高温烧结工艺采用震荡烧结工艺,具体过程为:先升温20min-50min至330℃-430℃,然后重复2-5次降温再升温过程,然后继续升温60min-120min至540℃-650℃并保温1h-3h,再升温60min-120min至780℃-900℃并保温1h-3h,继续升温20min-50min至900℃-980℃保温1h-3h,接着再升温30min-60min至1000℃-1100℃并保温3h-8h,最后进行后续时效处理,时效处理完成后出炉后得到烧结钕铁硼磁体,即稀土永磁材料,其中每次降温再升温过程为:先降温20min-50min,其中降温幅度为40℃-80℃,再升温20min-50min至330℃-430℃。(7) Under nitrogen protection atmosphere, the sintering boxes filled with blanks are stacked up and down according to the loading capacity, and a cover plate is placed on the top sintering box. Then, the stacked sintering boxes are placed in the furnace cavity of the sintering furnace in sequence by the way of furnace entry. The high-temperature sintering process adopts the oscillation sintering process. The specific process is: first heat up to 330℃-430℃ for 20min-50min, then repeat the process of cooling and heating up for 2-5 times, then continue to heat up to 540℃-650℃ for 60min-120min and keep warm for 1h-3h, and then heat up for 60min-120min. The sintered NdFeB magnet is prepared from the furnace at a temperature of 0min to 780℃-900℃ and kept at that temperature for 1h-3h, the temperature is continuously increased for 20min-50min to 900℃-980℃ and kept at that temperature for 1h-3h, and then the temperature is increased for 30min-60min to 1000℃-1100℃ and kept at that temperature for 3h-8h, and finally a subsequent aging treatment is carried out. After the aging treatment is completed, the sintered NdFeB magnet, i.e., a rare earth permanent magnet material, is obtained after being taken out of the furnace. The process of each cooling and then heating is as follows: first, the temperature is reduced for 20min-50min, in which the cooling amplitude is 40℃-80℃, and then the temperature is increased for 20min-50min to 330℃-430℃. 2.根据权利要求1所述的一种提高稀土永磁材料磁性能一致性的方法,其特征在于所述的第一凹槽、所述的第二凹槽、所述的第三凹槽和所述的第四凹槽沿竖直方向的截面均为等腰梯形,且该等腰梯形的下底位于其上底上方。2. According to claim 1, a method for improving the consistency of magnetic properties of rare earth permanent magnet materials is characterized in that the cross-sections of the first groove, the second groove, the third groove and the fourth groove along the vertical direction are all isosceles trapezoids, and the lower base of the isosceles trapezoid is located above its upper base. 3.根据权利要求1所述的一种提高稀土永磁材料磁性能一致性的方法,其特征在于所述的第一凹槽、所述的第二凹槽、所述的第三凹槽和所述的第四凹槽沿竖直方向的截面的高度均不超过5mm,且所述的第一凹槽、所述的第二凹槽、所述的第三凹槽和所述的第四凹槽沿竖直方向的截面的下底与上底的差值均不超过50mm,所述的第一凹槽的截面的面积为所述的矩形料腔的前侧面面积的1%-3%,所述的第二凹槽的截面的面积为所述的矩形料腔的后侧面面积的1%-3%,所述的第三凹槽的截面的面积为所述的矩形料腔的左侧面面积的1%-3%,所述的第四凹槽的截面的面积为所述的矩形料腔的右侧面面积的1%-3%。3. According to a method for improving the consistency of magnetic properties of rare earth permanent magnet materials described in claim 1, it is characterized in that the height of the cross section of the first groove, the second groove, the third groove and the fourth groove along the vertical direction does not exceed 5mm, and the difference between the lower bottom and the upper bottom of the cross section of the first groove, the second groove, the third groove and the fourth groove along the vertical direction does not exceed 50mm, the cross-sectional area of the first groove is 1%-3% of the front side area of the rectangular material cavity, the cross-sectional area of the second groove is 1%-3% of the rear side area of the rectangular material cavity, the cross-sectional area of the third groove is 1%-3% of the left side area of the rectangular material cavity, and the cross-sectional area of the fourth groove is 1%-3% of the right side area of the rectangular material cavity.
CN202310960548.XA 2023-08-02 2023-08-02 A sintering material box and method for improving the consistency of magnetic properties of rare earth permanent magnet materials Active CN116652182B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202310960548.XA CN116652182B (en) 2023-08-02 2023-08-02 A sintering material box and method for improving the consistency of magnetic properties of rare earth permanent magnet materials

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202310960548.XA CN116652182B (en) 2023-08-02 2023-08-02 A sintering material box and method for improving the consistency of magnetic properties of rare earth permanent magnet materials

Publications (2)

Publication Number Publication Date
CN116652182A CN116652182A (en) 2023-08-29
CN116652182B true CN116652182B (en) 2024-08-02

Family

ID=87721073

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202310960548.XA Active CN116652182B (en) 2023-08-02 2023-08-02 A sintering material box and method for improving the consistency of magnetic properties of rare earth permanent magnet materials

Country Status (1)

Country Link
CN (1) CN116652182B (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117727521B (en) * 2023-12-12 2025-10-31 福建省金龙稀土股份有限公司 Neodymium-iron-boron magnet material and preparation method thereof

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2004053147A (en) * 2002-07-22 2004-02-19 Imae Kogyo Kk Sintering setter
CN106601406A (en) * 2017-01-03 2017-04-26 京磁材料科技股份有限公司 Sintering method for preparing neodymium-iron-boron magnet
CN116313483A (en) * 2023-03-23 2023-06-23 包头韵升强磁材料有限公司 A Method for Reducing the Deformation of Thin Sintered NdFeB Magnets

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104729293B (en) * 2015-03-20 2017-03-01 重庆科技学院 A kind of flowing atmosphere thermal shock sintering resistance furnace
CN105935768B (en) * 2016-06-30 2018-02-27 中铝广西有色金源稀土有限公司 A kind of sintered NdFeB open type sintering magazine and its application method
CN108305771A (en) * 2017-09-12 2018-07-20 包头韵升强磁材料有限公司 A kind of preparation method of low brittleness neodymium-iron-boron magnetic material
CN207414335U (en) * 2017-10-17 2018-05-29 成都晨航磁业有限公司 A kind of sintering box for permanent magnet product production
CN112851376B (en) * 2020-12-31 2022-11-18 中国建筑材料科学研究总院有限公司 High-density fine-grain ceramic and preparation method and application thereof
CN114054753B (en) * 2021-11-22 2024-10-22 中钢天源股份有限公司 Material box for sintering neodymium iron boron and sintering method
CN115938709A (en) * 2022-11-30 2023-04-07 福建省长汀金龙稀土有限公司 A kind of magnetic steel containing high-abundance rare earth elements and its preparation method and application

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2004053147A (en) * 2002-07-22 2004-02-19 Imae Kogyo Kk Sintering setter
CN106601406A (en) * 2017-01-03 2017-04-26 京磁材料科技股份有限公司 Sintering method for preparing neodymium-iron-boron magnet
CN116313483A (en) * 2023-03-23 2023-06-23 包头韵升强磁材料有限公司 A Method for Reducing the Deformation of Thin Sintered NdFeB Magnets

Also Published As

Publication number Publication date
CN116652182A (en) 2023-08-29

Similar Documents

Publication Publication Date Title
CN103093921B (en) A kind of R-T-B-M-C system sintered magnet and manufacture method thereof and special purpose device
EP2348518B1 (en) Method for producing sintered rare earth magnet
CN102640238A (en) Rare earth anisotropic magnet and process for production thereof
CN111370192B (en) Sintered neodymium iron boron permanent magnet oxygen control preparation method and screening device
CN116652182B (en) A sintering material box and method for improving the consistency of magnetic properties of rare earth permanent magnet materials
US11881351B2 (en) Preparation method of ring-shaped sintered Nd—Fe—B magnet and its moulding die
KR101261099B1 (en) method for manufacturing rare earth sintering magnets
CN103000324A (en) Sintered rare earth permanent magnetic material and preparation method thereof
CN106011506A (en) Equipment and method for preparing nickel-base hydrogen storage alloy containing rare-earth, magnesium and boron
CN101178962B (en) A pressureless preparation method of rare earth-iron-boron sintered magnetic material
CN103996517A (en) Semi-automatic forming method of neodymium iron boron rare earth permanent magnetic material
CN203875346U (en) Air-stream milling device for pulverizing rare earth permanent magnetic material
CN103996518A (en) Forming method of neodymium iron boron rare earth permanent magnetic material
CN118231076A (en) Superfine high-performance sintered NdFeB magnet and preparation method thereof
US11222738B2 (en) Method for manufacturing rare earth magnet
CN116884756B (en) Preparation method of thin special-shaped magnetic steel
KR102012446B1 (en) Manufacturing method of high performance rare earth magnet
CN116313483B (en) A method for reducing the deformation of thin-film sintered NdFeB magnet blanks
CN111968814A (en) Powder distribution device and powder distribution method thereof, and manufacturing method of NdFeB series sheet magnet
CN106653269B (en) Make the process and its tooling of high consistency sintered Nd-Fe-B permanent magnet
JP4240988B2 (en) Rare earth alloy granulated powder manufacturing method, rare earth alloy granulated powder manufacturing apparatus, and rare earth alloy sintered body manufacturing method
CN120784066A (en) Sintering material box and method for improving size and performance of sintered NdFeB product
CN114709062B (en) A manufacturing method for improving the temperature resistance of traction machine magnets
CN221125712U (en) Automatic profiling system
CN118538496B (en) Sintered NdFeB magnet containing cerium and its anisostatic pressing preparation method

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant