CN110504077A - A kind of Nd-Fe-B permanent magnet material and preparation method thereof - Google Patents
A kind of Nd-Fe-B permanent magnet material and preparation method thereof Download PDFInfo
- Publication number
- CN110504077A CN110504077A CN201910657018.1A CN201910657018A CN110504077A CN 110504077 A CN110504077 A CN 110504077A CN 201910657018 A CN201910657018 A CN 201910657018A CN 110504077 A CN110504077 A CN 110504077A
- Authority
- CN
- China
- Prior art keywords
- magnet material
- permanent magnet
- permanent
- degrees celsius
- powder
- 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.)
- Pending
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D6/00—Heat treatment of ferrous alloys
- C21D6/007—Heat treatment of ferrous alloys containing Co
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C33/00—Making ferrous alloys
- C22C33/006—Making ferrous alloys compositions used for making ferrous alloys
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C33/00—Making ferrous alloys
- C22C33/02—Making ferrous alloys by powder metallurgy
- C22C33/0257—Making ferrous alloys by powder metallurgy characterised by the range of the alloying elements
- C22C33/0278—Making ferrous alloys by powder metallurgy characterised by the range of the alloying elements with at least one alloying element having a minimum content above 5%
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C33/00—Making ferrous alloys
- C22C33/04—Making ferrous alloys by melting
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/002—Ferrous alloys, e.g. steel alloys containing In, Mg, or other elements not provided for in one single group C22C38/001 - C22C38/60
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/005—Ferrous alloys, e.g. steel alloys containing rare earths, i.e. Sc, Y, Lanthanides
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/10—Ferrous alloys, e.g. steel alloys containing cobalt
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/12—Ferrous alloys, e.g. steel alloys containing tungsten, tantalum, molybdenum, vanadium, or niobium
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F1/00—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties
- H01F1/01—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials
- H01F1/03—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity
- H01F1/032—Magnets 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
- H01F1/04—Magnets 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
- H01F1/047—Alloys characterised by their composition
- H01F1/053—Alloys characterised by their composition containing rare earth metals
- H01F1/055—Alloys characterised by their composition containing rare earth metals and magnetic transition metals, e.g. SmCo5
- H01F1/057—Alloys characterised by their composition containing rare earth metals and magnetic transition metals, e.g. SmCo5 and IIIa elements, e.g. Nd2Fe14B
- H01F1/0571—Alloys 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
- H01F1/0575—Alloys 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
- H01F1/0577—Alloys 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
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F41/00—Apparatus 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
- H01F41/02—Apparatus 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
- H01F41/0253—Apparatus 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
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F41/00—Apparatus 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
- H01F41/02—Apparatus 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
- H01F41/0253—Apparatus 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
- H01F41/0266—Moulding; Pressing
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Power Engineering (AREA)
- Manufacturing & Machinery (AREA)
- Crystallography & Structural Chemistry (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Inorganic Chemistry (AREA)
- Hard Magnetic Materials (AREA)
Abstract
The invention discloses a kind of Nd-Fe-B permanent magnet materials and preparation method thereof, belong to permanent-magnet material technical field, it is characterized in that: a kind of Nd-Fe-B permanent magnet material, permanent-magnet material includes following weight percentage components: neodymium 30-45%, niobium 2-2.5%, cobalt 2.5-4.2%, zinc 0.15-0.2%, gallium 0.2-0.5%, boron 2.5-4.8%, tungsten 0.1-0.5%, thulium oxide 2.5-4%, surplus are iron.The preparation method of above-mentioned Nd-Fe-B permanent magnet material include: weighing and ingredient, melting, powder processed, magnetic field magnetize, die mould, high temperature sintering, high tempering, lonneal, and be packed and stored after examining.The present invention effectively raises the coercivity of Nd-Fe-B permanent magnet material entirety, makes it have the excellent properties for improving squareness and improving temperature stability.
Description
Technical field
The invention belongs to permanent-magnet material technical fields, more specifically, it relates to a kind of Nd-Fe-B permanent magnet material and its system
Preparation Method.
Background technique
High brands of sintered Nd-Fe-B typically refers to the material with high remanent magnetism, and the remanent magnetism of material directly determines that material is processed
It is strong and weak at the final finished performance after finished product, with the continuous expansion of material application field, the remanent magnetism of material is required increasingly
It is high.
Nd-Fe-B permanent magnet material is due to its brilliant performance (high remanent magnetism, high-coercive force, high energy product), it has also become modern section
The indispensable important material base in skill field, the demand of neodymium iron boron have obtained large increase.With new-energy automobile and height
Hold equipment development, it is higher and higher to the performance requirement of NdFeB material, especially permanent-magnet material manufacture instrument and equipment or device
Part is not generally possible to work at a constant temperature, and traditional pure neodymium-iron-boron magnetic material as the temperature rises, demagnetizes
The phenomenon that, therefore in order to meet the application demand of high-end devices, need high temperature resistance and magnetism to Nd-Fe-B permanent magnet material
It can be carried out improvement, it is desirable to obtain the product with high-Curie-point, high-coercive force for adapting to hot operation.Since sintered magnet is usual
Double sintering and mill processing are needed, and the dimensional accuracy of bonded permanent magnet is high, freedom degree is high, can be prepared into the magnetic of arbitrary shape
Body, and receive and be widely applied.
It exists in the prior art by the way of rare earth element is added in Nd-Fe-B permanent magnet material and is prepared into bonding magnetic powder
Improve the high temperature resistance and magnetic energy product of NdFeB material itself.But rare earth element is different in bonding magnetic powder preparation process
Crystal habit, crystal phase structure, the degree of orientation and microstructure influence there is very big difference, if the gold of incorporation
Belong to element select it is improper can also have the defects that reduce bonding magnetic particle capability, therefore select suitable incorporation metallic element, maximum
The properties of the raising bonding magnetic powder of limit, become a technical problem to be solved urgently.
Summary of the invention
In view of the deficiencies of the prior art, the present invention intends to provide a kind of Nd-Fe-B permanent magnet material, effectively
The coercivity for improving Nd-Fe-B permanent magnet material entirety makes it have the superiority for improving squareness and improving temperature stability
Energy.
To achieve the above object, the present invention provides the following technical scheme that a kind of Nd-Fe-B permanent magnet material, permanent-magnet material packet
It includes following weight percentage components: neodymium 30-45%, niobium 2-2.5%, cobalt 2.5-4.2%, zinc 0.15-0.2%, gallium 0.2-
0.5%, boron 2.5-4.8%, tungsten 0.1-0.5%, thulium oxide 2.5-4%, surplus are iron.
By using above-mentioned technical proposal, coercivity is can be improved in the addition of niobium Nb, the main reason is that niobium is able to suppress
Grain growth, refines crystal grain, isolation crystal grain coupling, and the addition of gallium can reduce the angle of wetting of rich-Nd phase, inhibit growing up for T1, make
It obtains T1 phase interface defect concentration to reduce, magnetic reversal farmland is in interface forming core difficulty；And cobalt is primarily present in main phase and rich-Nd phase, cobalt
Have the function of improving Tc and reduce reversible loss, gallium, which combines addition with niobium or tungsten, can improve squareness, and can get suitable
Low irreversible loss, while part replaces iron using Nb, can improve temperature stability.It is comprehensive, effectively raise neodymium iron
The coercivity of B permanent magnetic material entirety makes it have the excellent properties for improving squareness and improving temperature stability.
Further, the thulium oxide is selected from thulium oxide ultra-micro powder.
Further, the preparation method of the thulium oxide ultra-micro powder includes: and prepares thulium hydroxide in ethanol solution to surpass
Micropowder is dispersed in ethanol solution immediately after being generated due to thulium hydroxide, prevents the growth and reunion of particle, therefore can obtain
Partial size is small and the thulium hydroxide ultramicron of good dispersion, roasted and can be obtained thulium oxide ultra-micro powder.
By using above-mentioned technical proposal, according to FTIR analysis it is found that ultra micro thulium oxide is than polycrystalline thulium oxide have it is higher
Surface-active, to the gases such as moisture in air and carbon dioxide have strong suction-operated caused by, the Tm- of ultra micro thulium oxide
The absorptance polycrystalline of O key, which absorbs, has small blue shift, and absorption intensity dies down, due to the reduction with grain size, lattice constant
Also it reduces, i.e. the Tm-O key of ultra micro thulium oxide is shorter than the bond distance of polycrystalline thulium oxide, and Tm-O bond strength increases, so ultra micro thulium oxide
There is higher wave number than the absorption of polycrystalline thulium oxide, that is, small blue shift has occurred.
Further, the permanent-magnet material further includes the copper of 0.15-0.2%.
By using above-mentioned technical proposal, nonmagnetic Cu can improve the micro-structure of grain boundary, after copper enters magnet
It is preferentially enriched in main phase grain surface, plays the role of reducing main phase grain surface energy, to change the shape of crystal grain, main phase
Crystal grain, which is grown up, receives the influence of copper atom diffusion, hinders main phase grain and is up to, leads to the refinement of crystal grain, Gu coercivity increases.
Also, when the elements such as copper and cobalt, niobium, gallium carry out comprehensive function, above-mentioned permanent-magnet material intrinsic coercive with higher can be made
Power and certifiable permanent-magnet material remanent magnetism with higher.
The present invention also provides following technical solutions: a kind of preparation method of Nd-Fe-B permanent magnet material, including operates as follows
Step:
Step 1: weighing and ingredient；
Step 2: melting: it charges taken out again very to 1Pa hereinafter, beginning to warm up first, Bian Jiare continues on side to be evacuated, it is increased with temperature,
The gas of adsorbed state, moisture content are gradually desorbed and are extracted, until kermesinus is generally presented in furnace charge, is closed valve and are filled with argon gas, increased
Power is warming up to furnace charge and all melts, and carries out refining in 5 minutes or so, and refining, which finishes, to be subtracted power and be poured, when casting
Cast gate should be directed at cooling mould, be poured and cooled down, obtain alloy block；
Step 3: powder processed: the obtained alloy block in step 2 being crushed through crusher, then plus in right amount air, in ball
Ground in mill, be followed by stirring for be uniformly mixed obtain powder；
Step 4: magnetic field is magnetized；
Step 5: die mould: by the powder after weighing through press compression moulding, static pressure obtained green compact after 1-2.5 hours；
Step 6: high temperature sintering: microwave vacuum sintering furnace is sintered, and sintering temperature is 1050-1200 degrees Celsius；
Step 7: high tempering: the sintered magnet block for first obtaining step 6 is heated to 900-1000 degrees Celsius of tempering
After extract it is cold, then again through 580-600 degrees Celsius be tempered；Then extract after being again heated to 850-960 degrees Celsius it is cold, then again through 580-
600 degrees Celsius of tempering；
Step 8: lonneal: being tempered at 560-620 degrees Celsius, then come out of the stove and be cooled to room temperature；
Step 9: it is packed and stored after inspection.
Further, high temperature sintering, high tempering and lonneal get off to entire technical process of coming out of the stove generally want 20~
Between 38 hours.
Further, in step 5, the density of the green compact is about 3.2-4.5g/cm3。
By using above-mentioned technical proposal, it is weighed first according to recipe requirements, then its melting is formed and is closed
Gold bullion, all raw material that then this process of powder processed obtains mix each ingredient of powder that is relatively more abundant and obtaining also relatively
It is even.Operation of magnetizing then is carried out in magnetic field, it is subjected to operation of magnetizing prior to die mould, it can be with by optimization aforesaid operations mode
The important way of the comprehensive magnetic energy of Nd-Fe-B permanent magnet material is improved, its intrinsic coercivity of the material sample through compacting of magnetizing is handed over
Bottom, remanent magnetism and maximum magnetic flux product can be lower；And the molding material sample that do not magnetize is higher with respect to intrinsic coercivity, remanent magnetism and maximum magnetic flux
Product can be lower.Be subsequently compressed into type, then the permanent-magnet material obtained after high temperature sintering handled via double tempering after can be improved
Above-mentioned mechanical strength keeps its structure and performance more stable.It is not only easy to operate from there through the above-mentioned preparation manipulation of use,
And the whole coercivity of Nd-Fe-B permanent magnet material can also be improved, making it have improves squareness and improvement temperature stability
Excellent properties.
Further, one layer of W metal or metal Zn is electroplated on the blank obtained in step 5 after polishing.
By using above-mentioned technical proposal, can be used in the environment of being air-dried and there is no corrosive gas, electricity
The W metal or Zn of plating can effectively increase its anti-oxidant and corrosion resistance.
Further, in step 7, it is necessary first to carry out Pre-treatment before plating, concrete operations mode is using ultrasonic wave
Cleaning, the cleaning power control of the ultrasonic wave is in 1000-1200w, ultrasonic power density about 0.5-0.8w/cm2。
By using above-mentioned technical proposal, the pre-treatment of neodymium iron boron plating generally uses multiple tracks ultrasonic cleaning, because ultrasonic
The cavitation of wave is conducive to make the substances such as greasy dirt, the soda acid in neodymium iron boron micropore to be thoroughly removed, otherwise can be because in micropore
" dirt " cleaning dirty influence treatment before plating quality, influences binding force of cladding material.In addition, ultrasonic cleaning is additionally favorable for removing neodymium iron boron
The boron ash that surface generates in pickling, further eliminates binding force hidden danger.
In conclusion the invention has the following advantages:
1, the present invention effectively raises the coercivity of Nd-Fe-B permanent magnet material entirety, and making it have improves squareness and improvement
The excellent properties of temperature stability；
2, optimize, the preparation manipulation of above-mentioned Nd-Fe-B permanent magnet material is not only easy to operate, but also can also improve Nd-Fe-B permanent magnetic
The whole coercivity of material, makes it have the excellent properties for improving squareness and improving temperature stability；
3, optimize, the pre-treatment of neodymium iron boron plating generally uses multiple tracks ultrasonic cleaning, because the cavitation of ultrasonic wave is conducive to
The substances such as the greasy dirt in neodymium iron boron micropore, soda acid are thoroughly removed, it otherwise can be because of " dirt " cleaning dirty shadow in micropore
Treatment before plating quality is rung, binding force of cladding material is influenced.In addition, ultrasonic cleaning is additionally favorable for removing neodymium iron boron surface generation in pickling
Boron ash, further eliminate binding force hidden danger.
Detailed description of the invention
Fig. 1 is the process flow chart of one of embodiment in a kind of preparation method of Nd-Fe-B permanent magnet material.
Specific embodiment
Below in conjunction with attached drawing, invention is further described in detail.
One, embodiment
Embodiment 1: a kind of Nd-Fe-B permanent magnet material, permanent-magnet material include following weight percentage components: neodymium 30%, niobium 2%,
Cobalt 2.5%, zinc 0.15%, gallium 0.2%, boron 2.5%, tungsten 0.1%, thulium oxide ultra-micro powder 2.5%, surplus are iron.
Preparation method, as shown in Figure 1, including following operating procedure:
Step 1: weighing and ingredient: weighing obtain following raw material, neodymium 30kg, niobium 2kg, cobalt 2.5kg, zinc 0.15kg, gallium respectively
0.2kg, boron 2.5kg, tungsten 0.1kg, thulium oxide ultra-micro powder 2.5kg, iron 60.05kg.
Step 2: melting: all components in step 1 being fitted into smelting furnace first, then are taken out very to 1Pa hereinafter, starting
Heating, Bian Jiare continue on side to be evacuated (air), increase with temperature, and the gas of adsorbed state, moisture content is gradually desorbed and is extracted, until
Kermesinus is generally presented in furnace charge, closes valve and is filled with argon gas, carries out increasing power and is warming up to furnace charge all fusings, and carries out 5 minutes or so
Refining, refining finishes and subtracts power and be poured, and cast gate should be directed at cooling mould when casting, is poured and is cooled down, is obtained
To alloy block.
Step 3: powder processed: the obtained alloy block in step 2 is crushed through crusher, then plus in right amount air,
It is ground in rolling ball milling, ratio of grinding media to material 10:1, the medium of ball milling uses 120# aviation gasoline, and ball grinder uses stainless steel
Tank, sphere use steel ball, and tetra- kinds of diameter 2mm, 5mm, 8mm and 10mm, and the weight of each steel ball is consistent；Then have above-mentioned
The powder material that ball milling obtains again via airflow milling (pushed using ultrasonic air-flow mutually collided between lower powder and into
Row refinement)；20-30min finally is mixed according to 300 revs/min of mixing speed, obtains uniform, tiny, pure alloy
Powder, being added in ball milling has antioxidant, and above-mentioned antioxidant can be using application No. is in CN201410364143.0
A kind of Nd Fe B alloys powder antioxidant announced in the embodiment 1 of state's patent of invention, while the grain of above-mentioned alloy powder
Diameter is controlled at 5 μm or so, and is had good uniformity.
Step 4: magnetic field is magnetized: it magnetizes and suppresses on the same device with moulding integrated process via magnetizing, and
It is handled in the way of first magnetizing and suppressing afterwards.Wherein, the mode to magnetize is: capacitor is first filled with high direct voltage voltage,
Then the coil discharge minimum by a resistance, for the peak value of discharge pulse current up to tens of thousands of amperes, this current impulse is online
A powerful magnetic field is generated in circle, which makes to be placed in the hard magnetic material permanent magnetization in coil.
Step 5: die mould: magnetize reach highest when, with glue stick tap upper mould so that magnetic powder is substantially preliminary
It compresses, is then suppressed on press, static pressure obtains green compact after 1 hour, and controls the density of above-mentioned green compact in 3.2g/cm3Left and right；
One layer of metal Zn is electroplated on the blank obtained in step 5 after polishing.
Step 6: high temperature sintering: microwave vacuum sintering furnace is sintered, and the range of medium wavelength is 1mm-1m, sintering temperature
Degree is 1050-1200 degrees Celsius；It can utilize the dielectric loss of material in microwave electromagnetic field that material is integrally heated to
Sintering temperature and the Fast Sintering mode for realizing densification.
Step 7: high tempering: firstly the need of Pre-treatment before plating is carried out, concrete operations mode is clear using ultrasonic wave
It washes, the cleaning power control of the ultrasonic wave is in 1000w, ultrasonic power density about 0.5w/cm2.Then again by step 6
Obtained sintered magnet block be heated to 900 degrees Celsius tempering after extract it is cold, then again through 580-600 degrees Celsius be tempered；Then
Extract after being again heated to 850 degrees Celsius it is cold, then again through 580-600 degrees Celsius be tempered.
Step 8: lonneal: being tempered at 560 degrees Celsius, then come out of the stove and be cooled to room temperature.
Step 9: it is packed and stored after inspection.
Embodiment 2: a kind of Nd-Fe-B permanent magnet material, permanent-magnet material include following weight percentage components: neodymium 36%, niobium
2.2%, cobalt 3%, zinc 0.18%, gallium 0.3%, boron 3%, tungsten 0.2%, thulium oxide ultra-micro powder 3%, surplus are iron.
Step 1: weighing and ingredient: weighing obtain following raw material, neodymium 36kg, niobium 2.2kg, cobalt 3kg, zinc respectively
0.18kg, gallium 0.3kg, boron 3kg, tungsten 0.2kg, thulium oxide ultra-micro powder 3kg, iron 52.12kg.
Step 2: melting: all components in step 1 being fitted into smelting furnace first, then are taken out very to 1Pa hereinafter, starting
Heating, Bian Jiare continue on side to be evacuated (air), increase with temperature, and the gas of adsorbed state, moisture content is gradually desorbed and is extracted, until
Kermesinus is generally presented in furnace charge, closes valve and is filled with argon gas, carries out increasing power and is warming up to furnace charge all fusings, and carries out 5 minutes or so
Refining, refining finishes and subtracts power and be poured, and cast gate should be directed at cooling mould when casting, is poured and is cooled down, is obtained
To alloy block.
Step 3: powder processed: the obtained alloy block in step 2 is crushed through crusher, then plus in right amount air,
It is ground in rolling ball milling, ratio of grinding media to material 10:1, the medium of ball milling uses 120# aviation gasoline, and ball grinder uses stainless steel
Tank, sphere use steel ball, and tetra- kinds of diameter 2mm, 5mm, 8mm and 10mm, and the weight of each steel ball is consistent；Then have above-mentioned
The powder material that ball milling obtains again via airflow milling (pushed using ultrasonic air-flow mutually collided between lower powder and into
Row refinement)；25min finally is mixed according to 400 revs/min of mixing speed, obtains uniform, tiny, pure alloyed powder
Material, being added in ball milling has antioxidant, and above-mentioned antioxidant can be using application No. is the China of CN201410364143.0
A kind of Nd Fe B alloys powder antioxidant announced in the embodiment 1 of patent of invention, while the partial size of above-mentioned alloy powder
Control has good uniformity at 5 μm or so.
Step 4: magnetic field is magnetized: it magnetizes and suppresses on the same device with moulding integrated process via magnetizing, and
It is handled in the way of first magnetizing and suppressing afterwards.Wherein, the mode to magnetize is: capacitor is first filled with high direct voltage voltage,
Then the coil discharge minimum by a resistance, for the peak value of discharge pulse current up to tens of thousands of amperes, this current impulse is online
A powerful magnetic field is generated in circle, which makes to be placed in the hard magnetic material permanent magnetization in coil.
Step 5: die mould: magnetize reach highest when, with glue stick tap upper mould so that magnetic powder is substantially preliminary
It compresses, is then suppressed on press, static pressure obtains green compact after 2 hours, and controls the density of above-mentioned green compact in 4.2g/cm3Left and right；
One layer of W metal is electroplated on the blank obtained in step 5 after polishing smooth.
Step 6: high temperature sintering: microwave vacuum sintering furnace is sintered, and the range of medium wavelength is 1mm-1m, sintering temperature
Degree is 1050-1200 degrees Celsius；It can utilize the dielectric loss of material in microwave electromagnetic field that material is integrally heated to
Sintering temperature and the Fast Sintering mode for realizing densification.
Step 7: high tempering: firstly the need of Pre-treatment before plating is carried out, concrete operations mode is clear using ultrasonic wave
It washes, the cleaning power control of the ultrasonic wave is in 1000-1200w, ultrasonic power density about 0.65w/cm2.Then again will
The sintered magnet block that step 6 obtains be heated to 950 degrees Celsius tempering after extract it is cold, then again through 590 degrees Celsius be tempered；So
After be again heated to 890 degrees Celsius after extract it is cold, then again through 580-600 degrees Celsius be tempered.
Step 8: lonneal: being tempered at 600 degrees Celsius, then come out of the stove and be cooled to room temperature.
Step 9: it is packed and stored after inspection.
Embodiment 3: a kind of Nd-Fe-B permanent magnet material, permanent-magnet material include following weight percentage components: neodymium 45%, niobium
2.5%, cobalt 4.2%, zinc 0.2%, gallium 0.5%, boron 4.8%, tungsten 0.5%, thulium oxide ultra-micro powder 4%, surplus are iron.
Step 1: weighing and ingredient: weighing obtain following raw material, neodymium 45kg, niobium 2.5kg, cobalt 4.2kg, zinc respectively
0.2kg, gallium 0.5kg, boron 4.8kg, tungsten 0.5kg, thulium oxide ultra-micro powder 4kg, iron 38.3kg.
Step 2: melting: all components in step 1 being fitted into smelting furnace first, then are taken out very to 1Pa hereinafter, starting
Heating, Bian Jiare continue on side to be evacuated (air), increase with temperature, and the gas of adsorbed state, moisture content is gradually desorbed and is extracted, until
Kermesinus is generally presented in furnace charge, closes valve and is filled with argon gas, carries out increasing power and is warming up to furnace charge all fusings, and carries out 5 minutes or so
Refining, refining finishes and subtracts power and be poured, and cast gate should be directed at cooling mould when casting, is poured and is cooled down, is obtained
To alloy block.
Step 3: powder processed: the obtained alloy block in step 2 is crushed through crusher, then plus in right amount air,
It is ground in rolling ball milling, ratio of grinding media to material 10:1, the medium of ball milling uses 120# aviation gasoline, and ball grinder uses stainless steel
Tank, sphere use steel ball, and tetra- kinds of diameter 2mm, 5mm, 8mm and 10mm, and the weight of each steel ball is consistent；Then have above-mentioned
The powder material that ball milling obtains again via airflow milling (pushed using ultrasonic air-flow mutually collided between lower powder and into
Row refinement)；30min finally is mixed according to 500 revs/min of mixing speed, obtains uniform, tiny, pure alloyed powder
Material, being added in ball milling has antioxidant, and above-mentioned antioxidant can be using application No. is the China of CN201410364143.0
A kind of Nd Fe B alloys powder antioxidant announced in the embodiment 1 of patent of invention, while the partial size of above-mentioned alloy powder
Control has good uniformity at 5 μm or so.
Step 4: magnetic field is magnetized: it magnetizes and suppresses on the same device with moulding integrated process via magnetizing, and
It is handled in the way of first magnetizing and suppressing afterwards.Wherein, the mode to magnetize is: capacitor is first filled with high direct voltage voltage,
Then the coil discharge minimum by a resistance, for the peak value of discharge pulse current up to tens of thousands of amperes, this current impulse is online
A powerful magnetic field is generated in circle, which makes to be placed in the hard magnetic material permanent magnetization in coil.
Step 5: die mould: magnetize reach highest when, with glue stick tap upper mould so that magnetic powder is substantially preliminary
It compresses, is then suppressed on press, static pressure obtains green compact after 1-2.5 hours, and controls the density of above-mentioned green compact in 4.5g/cm3
Left and right；And one layer of W metal is electroplated on the blank obtained in step 5 after polishing.
Step 6: high temperature sintering: microwave vacuum sintering furnace is sintered, and the range of medium wavelength is 1mm-1m, sintering temperature
Degree is 1050-1200 degrees Celsius；It can utilize the dielectric loss of material in microwave electromagnetic field that material is integrally heated to
Sintering temperature and the Fast Sintering mode for realizing densification.
Step 7: high tempering: firstly the need of Pre-treatment before plating is carried out, concrete operations mode is clear using ultrasonic wave
It washes, the cleaning power control of the ultrasonic wave is in 1200w, ultrasonic power density about 0.8w/cm2.Then again by step 6
Obtained sintered magnet block be heated to 1000 degrees Celsius tempering after extract it is cold, then again through 600 degrees Celsius be tempered；Then add again
Heat is cold to extracting after 960 degrees Celsius, is then tempered again through 600 degrees Celsius.
Step 8: lonneal: being tempered at 620 degrees Celsius, then come out of the stove and be cooled to room temperature.
Step 9: it is packed and stored after inspection.
Embodiment 4: a kind of Nd-Fe-B permanent magnet material, difference from example 1 is that: in percentage by weight,
Permanent-magnet material further includes the copper for having 0.15%.
Embodiment 5: a kind of Nd-Fe-B permanent magnet material, difference from example 1 is that: in percentage by weight,
Permanent-magnet material further includes the copper for having 0.18%.
Embodiment 6: a kind of Nd-Fe-B permanent magnet material, difference from example 1 is that: in percentage by weight,
Permanent-magnet material further includes the copper for having 0.2%.
Two, comparative example
Comparative example 1: a kind of Nd-Fe-B permanent magnet material, difference from example 1 is that: permanent-magnet material only contain neodymium, boron and
Iron.
Comparative example 2: a kind of Nd-Fe-B permanent magnet material, difference from example 1 is that: permanent-magnet material includes following weight
Measure the component of percentage: neodymium 30-45%, niobium 2-2.5%, cobalt 2.5-4.2%, zinc 0.15-0.2%, boron 2.5-4.8%, oxidation
Thulium 2.5-4%, surplus are iron.
Three, Data Detection is proved
Test one: performance test
Subjects: using the neodymium iron boron magnetic body obtained in embodiment 1-6 as test specimen 1-6, using being obtained in comparative example 1-3
The neodymium iron boron magnetic body obtained is as control sample 1-2.
Test method: by test specimen 1-6 and control sample 1-2 according to GB/T13560-2017 " sintered NdFeB permanent magnet
Material " in regulation make standard sample, and it is right according to the method measurement test specimen 1-23 and control sample 1-3 institute in standard
Answer the coercivity (Hcj), remanent magnetism (Br) and magnetic energy product (BH) of neodymium iron boron magnetic body.
Test result: as shown in table 1 below, the coercivity of test specimen 1-6 controls between 1158-1175kA/m, and
Remanent magnetism controls between 1.485-1.497T, and magnetic energy product is controlled in 413-419kJ/m3Between.The coercive of test specimen 4-6 simultaneously
Power, remanent magnetism and magnetic energy product are all larger than the numerical value of test specimen 1-3, it can thus be appreciated that increasing copper in formula can effectively improve
Coercivity and certifiable permanent-magnet material remanent magnetism with higher, while its magnetic energy product is also corresponding higher.In addition, contrast sample 1-
2 indices are below the numerical value of test specimen 1-6, and the properties of contrast sample 2 are mentioned in contrast sample 1
Height, but difference reduction is larger for test specimen 1-6.It follows that above-mentioned Nd-Fe-B permanent magnet material specimen sample 1-6
Because the mating reaction between the elements such as the mating reaction between each element, especially tungsten, niobium, cobalt and gallium substantially increases it
The performance of coercivity, remanent magnetism etc..
The performance test results of table 1 test specimen 1-6 and control sample 1-2
Specific embodiment is only explanation of the invention, is not limitation of the present invention, and those skilled in the art are readding
It can according to need the modification that not creative contribution is made to the present embodiment after running through this specification, but as long as of the invention
All by the protection of Patent Law in scope of the claims.
Claims (9)
1. a kind of Nd-Fe-B permanent magnet material, which is characterized in that permanent-magnet material includes following weight percentage components: neodymium 30-
45%, niobium 2-2.5%, cobalt 2.5-4.2%, zinc 0.15-0.2%, gallium 0.2-0.5%, boron 2.5-4.8%, tungsten 0.1-0.5%, oxidation
Thulium 2.5-4%, surplus are iron.
2. a kind of Nd-Fe-B permanent magnet material according to claim 1, which is characterized in that the thulium oxide is super selected from thulium oxide
Micropowder.
3. a kind of Nd-Fe-B permanent magnet material according to claim 2, which is characterized in that the system of the thulium oxide ultra-micro powder
Preparation Method includes: that thulium hydroxide ultra-micro powder is prepared in ethanol solution, is dispersed in ethyl alcohol immediately after generating due to thulium hydroxide
In solution, the growth and reunion of particle are prevented, therefore can get that partial size is small and the thulium hydroxide ultramicron of good dispersion, it will
Its roasting can be obtained thulium oxide ultra-micro powder.
4. a kind of Nd-Fe-B permanent magnet material according to claim 3, which is characterized in that the permanent-magnet material further includes
The copper of 0.15-0.2%.
5. a kind of a kind of preparation method of Nd-Fe-B permanent magnet material, feature described in any one of -4 according to claim 1
It is, including following operating procedure:
Step 1: weighing and ingredient；
Step 2: melting: it charges taken out again very to 1Pa hereinafter, beginning to warm up first, Bian Jiare continues on side to be evacuated, it is increased with temperature,
The gas of adsorbed state, moisture content are gradually desorbed and are extracted, until kermesinus is generally presented in furnace charge, is closed valve and are filled with argon gas, increased
Power is warming up to furnace charge and all melts, and carries out refining in 5 minutes or so, and refining, which finishes, to be subtracted power and be poured, when casting
Cast gate should be directed at cooling mould, be poured and cooled down, obtain alloy block；
Step 3: powder processed: the obtained alloy block in step 2 being crushed through crusher, then plus in right amount air, in ball
Ground in mill, be followed by stirring for be uniformly mixed obtain powder；
Step 4: magnetic field is magnetized；
Step 5: die mould: by the powder after weighing through press compression moulding, static pressure obtained green compact after 1-2.5 hours；
Step 6: high temperature sintering: microwave vacuum sintering furnace is sintered, and sintering temperature is 1050-1200 degrees Celsius；
Step 7: high tempering: the sintered magnet block for first obtaining step 6 is heated to 900-1000 degrees Celsius of tempering
After extract it is cold, then again through 580-600 degrees Celsius be tempered；Then extract after being again heated to 850-960 degrees Celsius it is cold, then again through 580-
600 degrees Celsius of tempering；
Step 8: lonneal: being tempered at 560-620 degrees Celsius, then come out of the stove and be cooled to room temperature；
Step 9: it is packed and stored after inspection.
6. a kind of Nd-Fe-B permanent magnet material according to claim 5, which is characterized in that on the blank obtained in step 5
One layer of W metal or metal Zn are electroplated after polishing.
7. a kind of Nd-Fe-B permanent magnet material according to claim 5, which is characterized in that in step 7, it is necessary first into
Row Pre-treatment before plating, concrete operations mode are using ultrasonic cleaning, and the cleaning power control of the ultrasonic wave is in 1000-
1200w, ultrasonic power density about 0.5-0.8w/cm2。
8. a kind of preparation method of Nd-Fe-B permanent magnet material according to claim 5, which is characterized in that high temperature sintering, height
Temperature tempering and lonneal are got off to entire technical process of coming out of the stove generally to be wanted between 20 ~ 38 hours.
9. a kind of preparation method of Nd-Fe-B permanent magnet material according to claim 8, which is characterized in that in step 5,
The density of the green compact is about 3.2-4.5g/cm3.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910657018.1A CN110504077A (en) | 2019-07-19 | 2019-07-19 | A kind of Nd-Fe-B permanent magnet material and preparation method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910657018.1A CN110504077A (en) | 2019-07-19 | 2019-07-19 | A kind of Nd-Fe-B permanent magnet material and preparation method thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN110504077A true CN110504077A (en) | 2019-11-26 |
Family
ID=68586393
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910657018.1A Pending CN110504077A (en) | 2019-07-19 | 2019-07-19 | A kind of Nd-Fe-B permanent magnet material and preparation method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110504077A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110890212A (en) * | 2019-12-11 | 2020-03-17 | 杭州美时美刻物联网科技有限公司 | Manufacturing method of anti-corrosion permanent magnet device for servo motor |
| CN111370219A (en) * | 2020-04-22 | 2020-07-03 | 安徽吉华新材料有限公司 | Preparation process for producing new permanent magnet by full-cycle recycling of neodymium iron boron waste magnetic steel |
| CN112517602A (en) * | 2020-11-12 | 2021-03-19 | 北京工业大学 | Pretreatment method for recycling neodymium iron boron waste with adhesive tape oil sludge |
| CN112735715A (en) * | 2020-12-23 | 2021-04-30 | 江苏启诚磁业有限公司 | Preparation method of high-performance neodymium iron boron permanent magnet material |
Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| TWI238422B (en) * | 2002-11-14 | 2005-08-21 | Shinetsu Chemical Co | R-Fe-B sintered magnet |
| CN101872668A (en) * | 2009-04-23 | 2010-10-27 | 北京中科三环高技术股份有限公司 | Sintered NdFeB rear-earth permanent magnet with fine magnetization characteristic and manufacturing method thereof |
| CN103106991A (en) * | 2013-01-30 | 2013-05-15 | 浙江大学 | High-coercivity and high-stability neodymium iron boron magnet and preparation method based on crystal boundary reconstruction |
| CN104952578A (en) * | 2014-03-27 | 2015-09-30 | 日立金属株式会社 | R-T-B system alloy powder and R-T-B system sinter magnet |
| CN106158208A (en) * | 2016-08-29 | 2016-11-23 | 京磁材料科技股份有限公司 | A kind of tempering process of neodymium iron boron magnetic body |
| CN106169345A (en) * | 2016-08-29 | 2016-11-30 | 海安县建业磁材有限公司 | A kind of neodymium iron boron magnetic body and preparation method and neodymium iron boron magnetic body photo frame |
| CN106298138A (en) * | 2016-11-10 | 2017-01-04 | 包头天和磁材技术有限责任公司 | The manufacture method of rare-earth permanent magnet |
| CN106935352A (en) * | 2017-03-08 | 2017-07-07 | 江苏南方永磁科技有限公司 | A kind of complex phase magnetic material and preparation method |
| CN107256748A (en) * | 2017-06-20 | 2017-10-17 | 乳源瑶族自治县力强磁铁制品有限公司 | A kind of preparation method of high performance sintered neodymium-iron-boron rare earth permanent-magnetic material |
| CN108364736A (en) * | 2018-04-10 | 2018-08-03 | 陈亮 | A kind of Nd-Fe-B permanent magnet material and preparation method thereof |
| CN109754970A (en) * | 2017-11-01 | 2019-05-14 | 北京中科三环高技术股份有限公司 | A kind of rare-earth magnet and preparation method thereof |
-
2019
- 2019-07-19 CN CN201910657018.1A patent/CN110504077A/en active Pending
Patent Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| TWI238422B (en) * | 2002-11-14 | 2005-08-21 | Shinetsu Chemical Co | R-Fe-B sintered magnet |
| CN101872668A (en) * | 2009-04-23 | 2010-10-27 | 北京中科三环高技术股份有限公司 | Sintered NdFeB rear-earth permanent magnet with fine magnetization characteristic and manufacturing method thereof |
| CN103106991A (en) * | 2013-01-30 | 2013-05-15 | 浙江大学 | High-coercivity and high-stability neodymium iron boron magnet and preparation method based on crystal boundary reconstruction |
| CN104952578A (en) * | 2014-03-27 | 2015-09-30 | 日立金属株式会社 | R-T-B system alloy powder and R-T-B system sinter magnet |
| CN106158208A (en) * | 2016-08-29 | 2016-11-23 | 京磁材料科技股份有限公司 | A kind of tempering process of neodymium iron boron magnetic body |
| CN106169345A (en) * | 2016-08-29 | 2016-11-30 | 海安县建业磁材有限公司 | A kind of neodymium iron boron magnetic body and preparation method and neodymium iron boron magnetic body photo frame |
| CN106298138A (en) * | 2016-11-10 | 2017-01-04 | 包头天和磁材技术有限责任公司 | The manufacture method of rare-earth permanent magnet |
| CN106935352A (en) * | 2017-03-08 | 2017-07-07 | 江苏南方永磁科技有限公司 | A kind of complex phase magnetic material and preparation method |
| CN107256748A (en) * | 2017-06-20 | 2017-10-17 | 乳源瑶族自治县力强磁铁制品有限公司 | A kind of preparation method of high performance sintered neodymium-iron-boron rare earth permanent-magnetic material |
| CN109754970A (en) * | 2017-11-01 | 2019-05-14 | 北京中科三环高技术股份有限公司 | A kind of rare-earth magnet and preparation method thereof |
| CN108364736A (en) * | 2018-04-10 | 2018-08-03 | 陈亮 | A kind of Nd-Fe-B permanent magnet material and preparation method thereof |
Non-Patent Citations (1)
| Title |
|---|
| 唐杰等: "烧结NdFeB磁体相的继承性研究 ", 《稀有金属材料与工程》 * |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110890212A (en) * | 2019-12-11 | 2020-03-17 | 杭州美时美刻物联网科技有限公司 | Manufacturing method of anti-corrosion permanent magnet device for servo motor |
| CN110890212B (en) * | 2019-12-11 | 2021-07-20 | 杭州美时美刻物联网科技有限公司 | Manufacturing method of anti-corrosion permanent magnet device for servo motor |
| CN111370219A (en) * | 2020-04-22 | 2020-07-03 | 安徽吉华新材料有限公司 | Preparation process for producing new permanent magnet by full-cycle recycling of neodymium iron boron waste magnetic steel |
| CN111370219B (en) * | 2020-04-22 | 2021-07-20 | 安徽吉华新材料有限公司 | Preparation process for producing new permanent magnet by full-cycle recycling of neodymium iron boron waste magnetic steel |
| CN112517602A (en) * | 2020-11-12 | 2021-03-19 | 北京工业大学 | Pretreatment method for recycling neodymium iron boron waste with adhesive tape oil sludge |
| CN112735715A (en) * | 2020-12-23 | 2021-04-30 | 江苏启诚磁业有限公司 | Preparation method of high-performance neodymium iron boron permanent magnet material |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP7220330B2 (en) | RTB Permanent Magnet Material, Manufacturing Method, and Application | |
| CN110504077A (en) | A kind of Nd-Fe-B permanent magnet material and preparation method thereof | |
| CN107610858A (en) | A kind of amount containing cerium high inexpensive N35 neodymium iron boron magnetic bodies and its sintering method | |
| CN107316726A (en) | A kind of preparation method of sintered samarium cobalt magnet | |
| JP2021516870A (en) | Low B-containing R-Fe-B-based sintered magnet and manufacturing method | |
| CN106128673A (en) | A kind of Sintered NdFeB magnet and preparation method thereof | |
| CN111223624B (en) | Neodymium-iron-boron magnet material, raw material composition, preparation method and application | |
| CN109616310B (en) | High-coercivity sintered neodymium-iron-boron permanent magnet material and manufacturing method thereof | |
| CN103985533B (en) | Eutectic alloy Hydride Doped improves the coercitive method of Sintered NdFeB magnet | |
| CN111223627B (en) | Neodymium-iron-boron magnet material, raw material composition, preparation method and application | |
| WO2019223431A1 (en) | Low-cost diffusion source alloy, and grain boundary diffusion magnet and preparation method therefor | |
| JP7101448B2 (en) | Manufacturing method of sintered magnetic material | |
| CN105990019A (en) | Preparation method for low heavy rare earth sintered neodymium iron boron | |
| CN110323053B (en) | R-Fe-B sintered magnet and preparation method thereof | |
| CN108154986B (en) | Y-containing high-abundance rare earth permanent magnet and preparation method thereof | |
| CN110931197B (en) | Diffusion source for high-abundance rare earth permanent magnet | |
| CN108389676A (en) | A kind of temperature tolerance permanent-magnet material and preparation method thereof | |
| WO2019029000A1 (en) | Heat-resistant neodymium iron boron magnet and preparation method therefor | |
| CN110957089A (en) | Preparation method of samarium cobalt permanent magnet material | |
| CN112086255A (en) | High-coercivity and high-temperature-resistant sintered neodymium-iron-boron magnet and preparation method thereof | |
| CN108735413A (en) | One kind high-coercivity magnet of high-performance containing Tb and preparation method thereof | |
| CN113838622A (en) | High-coercivity sintered neodymium-iron-boron magnet and preparation method thereof | |
| CN104299743A (en) | Rare earth magnet | |
| CN108806910B (en) | Method for improving coercive force of neodymium iron boron magnetic material | |
| CN109509628B (en) | Preparation method of sintered neodymium iron boron composite powder |
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 | ||
| RJ01 | Rejection of invention patent application after publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20191126 |