WO2020118599A1 - 一种利用液氮高速球磨制备γ'-Fe4N软磁材料的方法 - Google Patents

一种利用液氮高速球磨制备γ'-Fe4N软磁材料的方法 Download PDF

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WO2020118599A1
WO2020118599A1 PCT/CN2018/120823 CN2018120823W WO2020118599A1 WO 2020118599 A1 WO2020118599 A1 WO 2020118599A1 CN 2018120823 W CN2018120823 W CN 2018120823W WO 2020118599 A1 WO2020118599 A1 WO 2020118599A1
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soft magnetic
magnetic material
liquid nitrogen
ball
ball milling
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French (fr)
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姜岩峰
李茹
姜淋馨
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江南大学
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    • H—ELECTRICITY
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    • 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
    • H01F1/12—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 soft-magnetic materials
    • H01F1/14—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 soft-magnetic materials metals or alloys
    • H01F1/147—Alloys characterised by their composition
    • H01F1/153—Amorphous metallic alloys, e.g. glassy metals
    • H01F1/15308—Amorphous metallic alloys, e.g. glassy metals based on Fe/Ni
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C1/00—Making non-ferrous alloys
    • C22C1/04—Making non-ferrous alloys by powder metallurgy
    • C22C1/05—Mixtures of metal powder with non-metallic powder
    • C22C1/051—Making hard metals based on borides, carbides, nitrides, oxides or silicides; Preparation of the powder mixture used as the starting material therefor
    • C22C1/053—Making hard metals based on borides, carbides, nitrides, oxides or silicides; Preparation of the powder mixture used as the starting material therefor with in situ formation of hard compounds
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    • B22F1/00—Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties
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    • B—PERFORMING OPERATIONS; TRANSPORTING
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    • B22F9/00—Making metallic powder or suspensions thereof
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F9/00—Making metallic powder or suspensions thereof
    • B22F9/16—Making metallic powder or suspensions thereof using chemical processes
    • 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
    • C22C33/0207—Using a mixture of prealloyed powders or a master alloy
    • C22C33/0228—Using a mixture of prealloyed powders or a master alloy comprising other non-metallic compounds or more than 5% of graphite
    • 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
    • H01F1/12—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 soft-magnetic materials
    • H01F1/14—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 soft-magnetic materials metals or alloys
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    • H—ELECTRICITY
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    • 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
    • H01F1/12—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 soft-magnetic materials
    • H01F1/14—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 soft-magnetic materials metals or alloys
    • H01F1/147—Alloys characterised by their composition
    • H01F1/153—Amorphous metallic alloys, e.g. glassy metals
    • H01F1/15333—Amorphous metallic alloys, e.g. glassy metals containing nanocrystallites, e.g. obtained by annealing
    • H—ELECTRICITY
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    • 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
    • H01F1/12—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 soft-magnetic materials
    • H01F1/14—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 soft-magnetic materials metals or alloys
    • H01F1/147—Alloys characterised by their composition
    • H01F1/153—Amorphous metallic alloys, e.g. glassy metals
    • H01F1/15341—Preparation processes therefor
    • H—ELECTRICITY
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    • 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
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F9/00—Making metallic powder or suspensions thereof
    • B22F9/02—Making metallic powder or suspensions thereof using physical processes
    • B22F9/04—Making metallic powder or suspensions thereof using physical processes starting from solid material, e.g. by crushing, grinding or milling
    • B22F2009/042—Making metallic powder or suspensions thereof using physical processes starting from solid material, e.g. by crushing, grinding or milling using a particular milling fluid
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F9/00—Making metallic powder or suspensions thereof
    • B22F9/02—Making metallic powder or suspensions thereof using physical processes
    • B22F9/04—Making metallic powder or suspensions thereof using physical processes starting from solid material, e.g. by crushing, grinding or milling
    • B22F2009/043—Making metallic powder or suspensions thereof using physical processes starting from solid material, e.g. by crushing, grinding or milling by ball milling
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F2302/00—Metal Compound, non-Metallic compound or non-metal composition of the powder or its coating
    • B22F2302/20—Nitride
    • H—ELECTRICITY
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    • 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
    • H01F41/0206—Manufacturing of magnetic cores by mechanical means
    • H01F41/0246—Manufacturing of magnetic circuits by moulding or by pressing powder

Definitions

  • the invention belongs to the field of soft magnetic materials, and particularly relates to a method for preparing ⁇ ′-Fe 4 N soft magnetic materials by using liquid nitrogen high-speed ball milling.
  • iron nitride materials have been studied, initially to study the nitriding phenomenon on the steel surface to improve the hardness and oxidation resistance of the steel surface.
  • iron nitride materials have excellent ferromagnetic properties, good wear resistance, corrosion resistance, oxidation resistance and other characteristics, and are good high-density magnetic recording media and thin-film magnetic heads Candidate material. Therefore, people began to conduct more in-depth research on iron nitride materials. Due to the different nitrogen content in iron nitride materials, iron nitride materials have different crystal structures and there are many phases, especially in the phases that exhibit strong ferromagnetism.
  • the saturation magnetization of ⁇ ′-Fe 4 N is second only to the maximum saturation magnetization value of ⁇ ′′-Fe 16 N 2 , but ⁇ ′-Fe 4 N has good thermal stability and low coercivity, which is an ideal It has the advantages of soft magnetic properties, good wear resistance, corrosion resistance, high hardness, high resistivity, etc. It is a potential magnetic storage medium and head material.
  • ⁇ ′-Fe 4 N is challenging. So far, most of the material preparation work is based on the preparation of thin film materials. There have been some reports on the preparation of granular materials, but the purity of ⁇ ′-Fe 4 N produced by the method is relatively low, and most of them are mixed with other iron nitride phases or other undesirable morphologies and particle sizes.
  • the method generally uses ammonia gas as the nitrogen source to provide nitrogen atoms.
  • the nitrogen content of the resulting material is generally about 6%, not more than 10%. It is a mixture containing lower ⁇ ′-Fe 4 N and it is difficult to achieve a pure phase. The excellent soft magnetic properties of ⁇ ′-Fe 4 N are affected.
  • the content of nitrogen atoms should be around 20%, but the solid solubility of nitrogen atoms in iron is only 11.7%, so according to the conventional nitrogen doping method, at most only ⁇ ′-Fe 4 N with a purity of about 50% is obtained, so the main obstacle that currently troubles the preparation of this material is the content of nitrogen atoms, how to overcome the solid solubility of nitrogen atoms in iron, so as to improve ⁇ ′-Fe 4
  • the purity of N is the bottleneck of the preparation of this material.
  • nano-scale ⁇ ′-Fe 4 N with a high volume phase ratio exhibit high permeability and low loss at high frequencies, and ultimately can achieve smaller devices, For example, transformers and inductors that operate in high-frequency semiconductor switches. Therefore, there is an urgent market demand for a pure phase nano-scale ⁇ ′-Fe 4 N soft magnetic material with high saturation magnetization, high permeability, low coercivity, and high resistivity.
  • the present invention has developed a method for preparing pure phase nanocrystalline ⁇ ′-Fe 4 N using liquid nitrogen high-speed ball milling.
  • liquid nitrogen is used to provide a low-temperature environment on one hand, and more importantly, liquid nitrogen is directly used as a nitrogen source, which overcomes the traditional use of ammonia as a nitrogen source to provide nitrogen atoms in ⁇ ′-Fe 4 N, resulting in low nitrogen content.
  • the iron raw material becomes very brittle, the surface volume ratio is very high, the nitrogen atoms are directly attached to the iron surface, forming a state of super saturation of nitrogen atoms, thus breaking the conventional Limitation of the solid solubility of nitrogen atoms in iron.
  • the present invention uses a high-energy low-temperature ball milling method in liquid nitrogen to prepare samples. It can use liquid nitrogen as a nitrogen source to obtain a Fe x N amorphous state with a certain degree of metastable supersaturation of Fe, and then anneal so that from ⁇ -iron To ⁇ ′-Fe 4 N phase transition.
  • the method of the present invention specifically treats the iron raw material and the ball-milled product in a nitrogen environment in the glove box, which protects the particles from oxidation, and cooperates with certain ball-milling conditions to obtain nano-sized Fe x N amorphous powder; then grinding The powder is annealed for phase transformation.
  • the annealing temperature is between 200°C and 300°C, which helps to activate nitrogen atoms, assist phase transformation and crystallize the ⁇ ′-Fe 4 N phase.
  • the first object of the present invention is to provide a method for preparing a ⁇ '-Fe 4 N soft magnetic material.
  • the method uses liquid nitrogen as a nitrogen source, including:
  • the weight ratio of the ball and iron powder material is 5:1 ⁇ 20:1, pour liquid nitrogen into the ball mill tank, and start the ball mill;
  • the method uses liquid nitrogen as a nitrogen source, combined with ball milling and annealing processes for preparation, including:
  • the weight ratio of the ball and iron raw material is 5:1 ⁇ 20:1, pour liquid nitrogen into the ball milling tank, and start ball milling;
  • the iron raw material includes iron powder.
  • the particle diameter of the iron powder is 10 nanometers to 1000 micrometers, and the purity is 90% to 100%.
  • the impurities therein may be carbon, manganese, zinc, oxygen, boron, cobalt, copper Wait.
  • the annealing temperature is 200°C to 350°C.
  • the annealing temperature is 250°C to 300°C.
  • the weight ratio of the ball to the iron powder material is 10:1.
  • the ball milling time in the step (1) is 1 h to 200 h.
  • the ball milling temperature in the step (1) is -196°C to 25°C.
  • the temperature of the ball mill in step (1) is maintained at the temperature of liquid nitrogen (-196°C).
  • the step (1) is performed at a rotation speed of 200 rpm to 10000 rpm.
  • the rotation speed of the ball mill in step (1) is 3000 rpm.
  • step (1) the ball mill is operated every 10 minutes to 10 hours, stopped for 1 minute to 1 hour, and then can be reversed or can continue to rotate forward.
  • step (1) the ball mill is stopped for five minutes every hour and then reversed.
  • the annealing is to place the sample in a nitrogen-filled reaction furnace and heat-anneal it at a temperature of 200°C to 350°C.
  • the method uses liquid nitrogen as a nitrogen source, combined with ball milling and annealing processes for preparation, including:
  • the weight ratio of the ball and iron raw material is 5:1 ⁇ 20:1, pour liquid nitrogen into the ball milling tank, and start ball milling;
  • the weight ratio of the ball to the iron raw material is 10:1.
  • the iron raw material in the step (1) includes iron powder, and the particle diameter of the iron powder is 10 nm to 1000 ⁇ m, and the purity is not less than 90%.
  • the ball milling temperature in the step (1) is -196°C to 25°C.
  • the temperature of the ball mill in step (1) is maintained at the temperature of liquid nitrogen (-196°C).
  • the step (1) is performed at a rotation speed of 200 rpm to 10000 rpm.
  • the rotation speed of the ball mill in step (1) is 3000 rpm.
  • step (1) the ball mill is operated every 10 minutes to 10 hours, stopped for 1 minute to 1 hour, and then can be reversed or can continue to rotate forward.
  • a second object of the present invention is to provide a ⁇ '-Fe 4 N soft magnetic material, the ⁇ '-Fe 4 N soft magnetic material is prepared using the method described above is obtained.
  • a third object of the present invention is to provide a transformer or inductor that operates in a high-frequency semiconductor switch, the transformer or inductor including the above-mentioned ⁇ '-Fe 4 N soft magnetic material.
  • the fourth object of the present invention is to apply the above ⁇ '-Fe 4 N soft magnetic material to power electronic devices.
  • the concept of the present invention is to use liquid nitrogen as a nitrogen source to generate nano-grain size during high-energy low-temperature cooling, and then through appropriate annealing treatment, ⁇ -iron can be directly converted into ⁇ ′-Fe 4 N without The appearance of any other Fe-N phase can basically achieve a pure phase (as shown in Figure 5).
  • the first step of the present invention is the high-energy low-temperature cooling process, which grinds the iron raw materials into small pieces by ball milling, the size of the diameter is about 40-80 nanometers, the ratio of surface area to volume increases, resulting in supersaturation of nitrogen, nitrogen atoms are adsorbed in On the surface; the second step is post-annealing.
  • the nanocrystallites are in the activated state.
  • nitrogen is moved into the particles, which occurs from the bcc (body-centered cubic structure ) To fcc (face-centered cubic structure) phase transformation, thereby obtaining ⁇ ′-Fe 4 N crystallites.
  • the present invention breaks through the traditional ammonia gas process, uses liquid nitrogen directly as the nitrogen source, and combines with the low-temperature cooling process to help reduce the size of the crystal structure, make the elements and structure more uniform, and overcome the nitrogen atoms in the Limitation of solid solubility in iron; after grinding, significant strain remains inside the sample, making the prepared powder more active.
  • Low temperature cooling in liquid nitrogen can cause nitridation reactions. Due to the low temperature of the grinding ball and the strong grinding effect, the particle size decreases to the nanometer level in a relatively short time.
  • the crystal size of the ground powder is about 40-80 nm, and the surface area and powder size show a similar trend to the crystallite size.
  • the method of the invention is a ball milling synthesis method in liquid nitrogen, which provides a new and highly feasible idea for the preparation of pure phase ⁇ ′-Fe 4 N materials.
  • the method of the present invention obtains nanocrystalline Fe x N with nitrogen atom supersaturation, the nitrogen atom adsorbed on the sample surface is as high as 22%, breaking through the solid solubility of iron (11.7%), and the post-annealing step to help from ⁇ -
  • the phase transition from Fe to ⁇ ′-Fe 4 N, the nitrogen content of which exceeds the saturation of ⁇ ′-Fe 4 N, can basically reach the pure phase.
  • the method of the invention prepares nanocrystalline ⁇ ′-Fe 4 N soft magnetic material, which has high Ms (155emu/g), low coercivity (0.7Oe) and high surface resistivity (375 ⁇ m), and can be applied to power electronic devices .
  • the method of the present invention can be used as a possible alternative method for mass production of high-grade soft magnetic materials with ideal magnetic properties, and has the advantages of high surface resistivity and low cost.
  • Figure 1 is the Auger (AES) energy spectrum of the material after high energy ball milling
  • Figure 2 is the XRD pattern of the material at different post-annealing temperatures
  • FIG. 3 is a hysteresis loop (VSM) diagram of the prepared material sample
  • Figure 4 is the SEM and TEM characterization of the prepared sample annealed after 300°C: (a) SEM image of the prepared sample; (b) diffraction pattern of the sample;
  • FIG. 5 is a schematic diagram of the phase transformation mechanism of ⁇ -Fe to ⁇ ′-Fe 4 N during the preparation process of the present invention; (a) pure iron with bcc structure; (b) low-temperature ball milling; (c) post-annealing phase conversion to ⁇ ′-Fe 4 N.
  • the starting material is pure iron with a purity of 99% (AlfaAesar); liquid nitrogen is provided by PRAXAIR; the high-energy ball mill system CM5100 (Luomen) operates in a planetary rotation mode.
  • the ratio of ball mass to sample mass is 10:1.
  • the tank is continuously cooled with liquid nitrogen from the integrated cooling system to make the sample brittle and retain volatility Nitrogen.
  • Liquid nitrogen circulates in the system and is continually replenished from the external filling system.
  • the external filling system is precisely controlled to keep the temperature at -196°C;
  • Iron raw materials and ball mill products are processed in a nitrogen environment inside the glove box, which protects the particles from oxidation.
  • the grinding time is 90 hours and the rotation speed is 3000 rpm.
  • Ball mill operation is stopped for 5 minutes every hour. The direction of rotation is reversed after each interval to help maintain the reaction in a uniform manner.
  • the ball milling is completed, put the ball tank into a glove box filled with nitrogen, and use magnets to collect the samples in the ball tank.
  • the ultrasonic method is used to help the samples attached to the tank wall and the ball to peel off. , So as to achieve the purpose of recycling.
  • the concentration of elements in the sample shows that the sample contains about 22% nitrogen;
  • Figure 2 is the XRD spectrum of the sample prepared by post-annealing. Annealing at 300°C results in more ⁇ ′-Fe 4 N peaks and sharper bcc Fe;
  • Figure 3 shows the hysteresis loop of the prepared sample.
  • the sample prepared by the low-temperature grinding step shows good soft magnetic properties, in which Ms 208emu/g and Hc 3.2 Oe, after post-annealing, the Ms value decreased slightly, about 155emu /g, which corresponds to the phase transition from ⁇ -Fe to ⁇ ′-Fe 4 N; however, in addition to the change in Ms, as the annealing temperature increases, the coercive force decreases (0.7 Oe), and the low coercive force
  • the ultrafine structure from the sample after the high-energy low-temperature cooling process in liquid nitrogen, with a grain size between 40 and 80 nm leads to low coercivity; on the other hand, the prepared sample has three phases, including ⁇ -Fe, amorphous Fe With ⁇ ′-Fe4N, the magnetostriction balance between the structural phases causes the magnetostriction in the prepared sample to approach zero, which is another important reason for the
  • the magnetic properties of the sample prepared by the present invention indicate that it is an ideal soft magnetic material.
  • the oversaturation of nitrogen in the sample of the present invention the sample resistivity measured up to 375 ⁇ m, indicating that the ⁇ ′-Fe 4 N material prepared by the present invention can be used for new transformer core materials with high performance and low cost;
  • Figure 4 is the SEM and TEM characterization results of the prepared sample: (a) SEM image of the prepared sample, SEM image shows the regular shape of the prepared sample; (b) TEM transmission diffraction pattern of the sample, showing the experimental HRTEM with clear contrast
  • the FFT of the image is characterized by the ⁇ ′-Fe 4 N phase. It can be observed that the nitride grows after the fibrous morphology. It can be determined that the image corresponds to the orientation around the [001] axis with the FCC structure and has the FCC structure.
  • the annealing temperature is replaced with 200°C or 250°C, and other conditions remain unchanged, and the ⁇ ′-Fe 4 N material is prepared.
  • the obtained material was characterized by XRD spectroscopy. As shown in FIG. 2, for the sample prepared after freeze grinding, it showed a broad bcc Fe peak, which was consistent with the metastable supersaturation of N to Fe. Annealing at 200°C for 10 minutes resulted in a slight change in the powder and a slight sharpening of the ⁇ '-Fe 4 N peak. Annealing at 250°C for 10 minutes resulted in sharp bcc Fe and ⁇ '-Fe4N peaks. Annealing at 300°C resulted in more ⁇ ′-Fe 4 N peaks and sharper bcc Fe.
  • the driving force for the phase change from ⁇ -Fe to ⁇ ′-Fe 4 N includes two parts: one is the surface activation energy of the abrasive particles, and the other is the annealing energy.
  • the annealing energy will affect the ⁇ ′-Fe 4 N produced.
  • higher annealing energy will make the volume ratio of ⁇ ′-Fe 4 N in the sample larger. As shown in FIG. 2, annealing at 300°C corresponds to ⁇ ′-Fe 4 N at 200°C and 250°C. The maximum volume ratio; however, further increase in annealing temperature cannot further improve the phase transformation.
  • the recrystallization of iron is the main reason for preventing the phase transformation from further improvement.
  • the crystallization temperature of iron is about 350 °C, and the post-annealing temperature above 350 °C will Helps increase the grain size of iron.
  • the growth of iron particles will prevent the phase transition of ⁇ -Fe to ⁇ ′-Fe 4 N. Therefore, post-annealing at 300°C corresponds to the optimized case, with the maximum annealing energy to assist the phase transition from ⁇ -Fe to ⁇ ′-Fe 4 N, while the temperature is lower than the crystallization temperature of iron.
  • ⁇ ′-Fe The total proportion of 4 N phase is about 35%; after annealing at 300 degrees Celsius, Ms is 155emu/g and the coercive force is 0.7Oe. According to XRD pattern calculation, the total proportion of ⁇ ′-Fe 4 N phase is 75% about.
  • Example 1 the weight ratio of the ball to the iron powder material is replaced from 10:1 to 30:1, and other conditions remain unchanged, and an iron-nitrogen material is prepared.
  • the magnetic properties of the obtained iron-nitrogen material are similar to those obtained in Example 1, and the yield is about 30% of that in Example 1.
  • the nitrogen source is replaced by liquid nitrogen with ammonia gas, and other conditions remain unchanged, and an iron-nitrogen material is prepared.
  • the obtained iron-nitrogen material has a nitrogen content of 6%, Ms of 185emu/g, coercive force of 10Oe, resistivity of 25 ⁇ m, and the resulting ⁇ ′-Fe 4 N phase accounts for about 10% of the overall proportion, as can be seen It is found that the proportion of ⁇ ′-Fe 4 N is relatively low, resulting in the overall performance of the prepared material being similar to that of pure iron.

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  • Soft Magnetic Materials (AREA)

Abstract

本发明公开了一种利用液氮高速球磨制备γ'-Fe4N软磁材料的方法，属于软磁材料领域。本发明方法利用液氮中的高能低温研磨来获得具有氮原子过饱和度的纳米材料FexN，由于低温下材料非常脆，表面体积比非常高，导致吸附在样品表面上的氮原子高达22％；300℃后退火使得α-Fe直接相变到γ'-Fe4N，从而制备纳米晶体γ'-Fe4N软磁材料。本发明方法操作简便、成本低，可大规模工业化生产，是一种新的制备理想磁性的高级软磁材料的替代方法。本发明方法制备的γ'-Fe4N软磁材料具有高Ms，低矫顽力和高表面电阻率的优势，能够用于高频半导体开关中操作的变压器和电感器。

Description

一种利用液氮高速球磨制备γ’-Fe 4N软磁材料的方法 技术领域
本发明属于软磁材料领域，具体涉及一种利用液氮高速球磨制备γ′-Fe 4N软磁材料的方法。
背景技术
20世纪50年代初期以来，人们就对氮化铁材料进行了研究，最初是为了研究钢铁表面的氮化现象，来提高钢铁表面的硬度和抗氧化能力。随着对氮化铁材料的深入研究，人们发现氮化铁材料具有优异的铁磁性能、良好的耐磨损、抗腐蚀、抗氧化等特性，是很好的高密度磁记录媒介和薄膜磁头的候选材料。于是人们开始了对氮化铁材料的更深入研究，由于氮化铁材料中氮含量的不同，氮化铁材料具有不同的晶体结构，存在很多相，特别是在表现出强铁磁性的相中，包括γ′-Fe 4N，α″-Fe 16N 2和ε-Fe 3N，已经被深入研究了50多年。尽管前人早就测得α″–Fe 16N 2相是“巨磁相”，但是，迄今为止，对α″–Fe 16N 2是否具有大的磁矩仍然处于争论当中。这主要是由于α″–Fe 16N 2是亚稳相，制备出单相的α″–Fe 16N 2是相对比较困难的。由于易分解，尽管制备出纯的α″–Fe 16N 2材料，在实际应用中也会受到较大的限制。γ′–Fe 4N的饱和磁化强度仅次于α″–Fe 16N 2的最大饱和磁化强度值，但γ′–Fe 4N的热稳定性好、矫顽力较小，是一种理想的软磁特性，并具有良好的耐磨损性、抗腐蚀性、高硬度、高电阻率等优点，是很有潜力的磁存储媒质和磁头材料。
然而，γ′-Fe 4N的制备具有挑战性，到目前为止，大多数材料制备工作都是基于薄膜材料的制备。已经有一些关于颗粒材料制备的报道，但是所采用的方法制得的γ′-Fe 4N纯度比较低，大部分混杂有其它的氮化铁相或其他不理想的形态和粒度，所采用的方法一般以氨气作为氮源来提供氮原子，所得材料含氮率一般都在6％左右，不超过10％，是含较低γ′-Fe 4N的混合物，很难达到纯相，严重影响了γ′-Fe 4N的优异的软磁特性。按照γ′-Fe 4N的原子比例的要求，其中氮原子的含量应该在20％左右，但铁中氮原子的固溶度仅有11.7％，所以按照常规氮掺杂的方法，最多只能得到50％左右纯度的γ′-Fe 4N，所以说，目前困扰该材料制备的最主要障碍就是氮原子含量的问题，如何克服铁中氮原子的固溶度，从而提高γ′-Fe 4N的纯度，是该材料制备的瓶颈。然而，对于其在功率电子器件中的实际应用，要求具有高体积相位比的纳米级γ′-Fe 4N在高频下表现出高磁导率和低损耗，最终能够实现更小的器件，例如在高频半导体开关中操作的变压器和电感器。因此，寻求一种高的饱和磁化强度，高磁导率，低矫顽力，高电阻率的纯相纳米级γ′-Fe 4N软磁材料是有迫切的市场需求的。
发明内容
为了解决上述问题，本发明开发了一种利用液氮高速球磨来制备纯相纳米晶γ′-Fe 4N的方法。其中，液氮一方面用于提供低温环境，更重要的是将液氮直接作为氮源，克服了传统以氨气作为氮源来提供γ′-Fe 4N中的氮原子，导致氮含量低的限制，而且在液氮温度下，通过球磨工艺控制，使铁原材料成为非常脆的状态，表面体积比非常高，氮原子直接附着在铁表面上，形成氮原子过度饱和的状态，从而突破常规氮原子在铁中固溶度的限制。本发明利用液氮中的高能低温球磨方法制备样品，能够以液氮作为氮源，获得具有一定程度的亚稳态过饱和度为Fe的Fe xN非晶态，然后退火使得从α-铁到γ′-Fe 4N的相变。得到具有特征磁性能和结构的良好的软磁材料，尤其是矫顽力超低，电阻率较高。本发明方法具体是将铁原料和球磨的产物在手套箱内的氮气环境中处理，其保护颗粒免于氧化，配合一定的球磨条件，得到纳米级粒度的Fe xN无定形粉末；然后将研磨的粉末后退火以进行相变，退火温度在200℃至300℃之间，有助于活化氮原子，辅助相变和结晶γ′-Fe 4N相。
本发明的第一个目的是提供一种γ’-Fe 4N软磁材料的制备方法，所述方法是利用液氮作为氮源，包括：
(1)铁原料放入高能球磨机中，球和铁粉材料的重量比是5：1～20：1，在球磨罐中冲入液氮，开始球磨；
(2)然后加热退火，即得γ’-Fe 4N软磁材料。
在本发明的一种实施方式中，所述方法是利用液氮作为氮源，结合球磨、退火工艺进行制备，包括：
(1)铁原料放入球磨机中，球和铁原料的重量比为5：1～20：1，在球磨罐中冲入液氮，开始球磨；
(2)然后加热250℃～300℃退火，即得γ′-Fe 4N软磁材料。
在本发明的一种实施方式中，所述铁原料包括铁粉。
在本发明的一种实施方式中，所述铁粉的颗粒直径为10纳米至1000微米，纯度为90％至100％，其中的杂质可以是碳、锰、锌、氧、硼、钴、铜等。
在本发明的一种实施方式中，所述退火温度为200℃～350℃。
在本发明的一种实施方式中，所述退火温度为250℃～300℃。
在本发明的一种实施方式中，所述球和铁粉材料的重量比是10：1。
在本发明的一种实施方式中，所述步骤(1)中球磨时间为1h至200h。
在本发明的一种实施方式中，所述步骤(1)中球磨温度为-196℃～25℃。
在本发明的一种实施方式中，所述步骤(1)中球磨温度保持液氮温度(-196℃)。
在本发明的一种实施方式中，所述步骤(1)是在转速200转/分钟至10000转/分钟下进行的。
在本发明的一种实施方式中，所述步骤(1)球磨的转速为3000转/分钟。
在本发明的一种实施方式中，所述步骤(1)中球磨机是每工作10分钟至10小时，停1分钟至1小时，然后可以反转或可以继续正转。
在本发明的一种实施方式中，所述步骤(1)中球磨机是每小时停五分钟，然后反转。
在本发明的一种实施方式中，所述退火是将将样品放入充满氮气的反应炉中加热退火，温度为200℃～350℃。
在本发明的一种实施方式中，所述方法是利用液氮作为氮源，结合球磨、退火工艺进行制备，包括：
(1)铁原料放入球磨机中，球和铁原料的重量比为5：1～20：1，在球磨罐中冲入液氮，开始球磨；
(2)然后加热250℃～300℃退火，即得γ′-Fe 4N软磁材料。
在本发明的一种实施方式中，所述球和铁原料的重量比为10：1。
在本发明的一种实施方式中，所述步骤(1)中铁原料包括铁粉，铁粉的颗粒直径为10纳米至1000微米，纯度不低于90％。
在本发明的一种实施方式中，所述步骤(1)中球磨温度为-196℃～25℃。
在本发明的一种实施方式中，所述步骤(1)中球磨温度保持液氮温度(-196℃)。
在本发明的一种实施方式中，所述步骤(1)是在转速200转/分钟至10000转/分钟下进行的。
在本发明的一种实施方式中，所述步骤(1)球磨的转速为3000转/分钟。
在本发明的一种实施方式中，所述步骤(1)中球磨机是每工作10分钟至10小时，停1分钟至1小时，然后可以反转或可以继续正转。
本发明的第二个目的是提供一种γ’-Fe 4N软磁材料，所述γ’-Fe 4N软磁材料是利用上述方法制备得到的。
本发明的第三个目的是提供一种高频半导体开关中操作的变压器或电感器，所述变压器或电感器包含上述的γ’-Fe 4N软磁材料。
本发明的第四个目的是将上述的γ’-Fe 4N软磁材料应用于功率电子器件中。
本发明的有益效果：
1、本发明的构思是利用液氮作为氮源，在高能低温冷却过程产生纳米晶粒尺寸，然后通过合适的退火处理，可以直接将α-铁转变为γ′-Fe 4N，而不会出现任何其他Fe-N相，基本能够达到纯相(如图5所示)。本发明第一步是高能低温冷却过程，它将铁原材料通过球磨的方法磨成小块，尺寸直径约为40-80纳米，表面积与体积的比率增加，产生氮的超饱和，氮原子吸附在表面上；第二步是后退火，对于表面上具有过饱和氮原子的颗粒，纳米微晶处于活化状态，在退火后温度的帮助下，氮被移入颗粒中，发生从bcc(体心立方结构)到fcc(面心立方结构)的相变，从而获得γ′-Fe 4N微晶。
2、与传统技术相比，本发明突破传统氨气工艺，以液氮直接作为氮源，结合低温冷却过程有助于减小晶体结构的尺寸，使元素和结构更均匀，克服了氮原子在铁中的固溶度的限制；研磨后，样品内部保留明显的应变，使制备的粉末更加活跃。液氮中的低温冷却可导致氮化反应。由于研磨球的低温和强烈的研磨效果，粒径在相对短的时间内降低到纳米级。研磨粉末的晶体尺寸约为40-80nm，表面积和粉末尺寸显示出与微晶尺寸类似的趋势。因为粉末在液氮温度下研磨，所以粉末极度脆化，但是在该过程中抑制了冷焊，在低温冷却过程中粉末变得更脆，都有助于粉末转化为无定形结构。本发明方法是在液氮中进行球磨合成方法，为纯相γ′-Fe 4N材料的制备提供了一种新的、可行性高的思路。
3、本发明方法获得具有氮原子过饱和度的纳米晶Fe xN，吸附在样品表面上的氮原子高达22％，突破铁的固溶度(11.7％)，后退火步骤以帮助从α-Fe到γ′-Fe 4N的相变，含氮量超过了γ′-Fe 4N的饱和度，基本可达纯相。本发明方法制备纳米晶体γ′-Fe 4N软磁材料，具有高Ms(155emu/g)，低矫顽力(0.7Oe)和高表面电阻率(375μΩ·m)，能够应用于功率电子器件。本发明方法可以用作可能的大规模生产具有理想磁性的高级软磁材料的替代方法，具有高表面电阻率和低成本的优点。
附图说明
图1为高能球磨后的材料的俄歇(AES)能谱；
图2为不同后退火温度下的材料的XRD图谱；
图3为制备的材料样品的磁滞回线(VSM)图；
图4为300℃后退火的制备样品上的SEM和TEM表征：(a)制备的样品的SEM图像；(b)样品的衍射图案；
图5为本发明制备过程中α-Fe到γ′-Fe 4N的相变机理的示意图；(a)具有bcc结构的纯 铁；(b)低温球磨；(c)后退火相转变为γ′-Fe 4N。
具体实施方式
实施例1：
起始原料是纯铁，纯度为99％(AlfaAesar)；液氮由PRAXAIR提供；高能球磨系统CM5100(Luomen公司)以行星旋转模式运行。
使用耐磨的不锈钢球作为研磨介质，球质与样品质量之比为10：1，在研磨过程之前和期间，用来自集成冷却系统的液氮连续冷却罐，使样品变脆并且保留了挥发性氮元素。液氮在系统中循环，并从外部灌装系统不断补充，外部灌装系统被精确控制，使温度始终保持在-196℃；
铁原料和球磨产物在手套箱内的氮气环境中处理，其保护颗粒免于氧化。研磨时间为90小时，而转速为3000rpm。球磨运行每小时停止5分钟。每个间隔后旋转方向反转，以帮助以均匀的方式保持反应。球磨完成后，把球罐放入充满氮气的手套箱中，利用磁铁把球罐中的样品收集起来，收集过程中辅助用超声的方法，使附着在罐壁和球上的样品都能够剥落下来，从而达到回收的目的。球磨后得到40-80nm纳米级粒度的FexN无定形粉末；将研磨的粉末放入退火炉中，退火炉中充满氮气，退火炉加热到300℃，使材料发生相变，得到γ′-Fe 4N材料。
对所得γ′-Fe 4N材料进行表征：
利用俄歇电子能谱(AES)在高能量低温研磨步骤后样品中元素浓度的结果，如图1所示，显示样品中约含有22％的氮；
图2为后退火制备样品的XRD光谱，300℃下退火得到更多的γ′-Fe 4N峰和更尖锐的bcc Fe；
图3显示了制备的样品的磁滞回线，通过低温研磨步骤制备的样品显示出良好的软磁性能，其中Ms 208emu/g和Hc 3.2 Oe，在后退火之后，Ms值略微下降，约155emu/g，这对应于从α-Fe到γ′-Fe 4N的相变；然而除了Ms的变化之外，随着退火温度的升高，矫顽力降低(0.7Oe)，低矫顽力来自在液氮中高能低温冷却过程后样品的超细结构，晶粒尺寸在40～80nm之间导致低矫顽力；另一方面，制备的样品具有三相，包括α-Fe，非晶Fe和γ′-Fe4N，结构相之间的磁致伸缩平衡导致制备的样品中的磁致伸缩接近零，这是理想的低矫顽力的另一个重要原因。总之，本发明制备的样品的磁性表明其是一种理想的软磁材料。此外，本发明样品中氮的过饱和，样品的电阻率测得高达375μΩ·m，说明本发明制备的γ′-Fe 4N材料能够用于具有高性能和低成本的新变压器磁芯材料；
图4是制备样品的SEM和TEM表征结果：(a)制备的样品的SEM图像，SEM图像显示制备的样品的规则形状；(b)样品的TEM透射衍射图案，显示了具有明确对比度的实验HRTEM图像的FFT，其特征在于γ′-Fe 4N相，可以观察到氮化物在纤维状形态之后生长，可以确定图像对应于具有FCC结构的[001]轴附近的取向，具有FCC结构。结合SEM和TEM表征的类似发现，验证了本发明球磨合成方法在液氮中的可行性。
实施例2：
参照实施例1的方法条件，将退火温度替换为200℃或者250℃，其他条件不变，制备的到γ′-Fe 4N材料。
所得的材料利用XRD光谱表征，如图2所示，对于冷冻研磨后制备的样品，它表现出宽的bcc Fe峰，与N转化为Fe的亚稳态过饱和度一致。在200℃下退火10分钟导致粉末稍微变化，γ′-Fe 4N峰的轻微锐化。在250℃下10分钟退火导致尖锐的bcc Fe和γ′-Fe4N峰。在300℃下退火导致更多的γ′-Fe 4N峰和更尖锐的bcc Fe。此外，进一步提高退火温度，略高于300℃，对XRD峰没有明显的影响；表明高能量低温冷却过程产生具有氮过饱和的宽BCC铁，短期后退火可导致尖锐的BCC和γ′-Fe 4N形成。
从α-Fe到γ′-Fe 4N的相变的驱动力包括两部分：一个是研磨颗粒的表面活化能，另一种是退火能量。使用相同的低温材料，表面活化能没有差异，因此退火能量会对产生的γ′-Fe 4N产生影响。一方面，较高的退火能量将使样品中γ′-Fe 4N的体积比更大，如图2所示，300℃下的退火对应于γ′-Fe 4N与200℃和250℃下的最高体积比；然而，退火温度的进一步增加不能进一步改善相变，铁的重新结晶是阻止相变进一步改善的主要原因，铁的结晶温度约为350℃，温度高于350℃的后退火将有助于增加铁的晶粒尺寸。铁粒子的生长将阻止α-Fe向γ′-Fe 4N的相变。因此，在300℃下的后退火对应于优化的情况，具有最大退火能量以辅助从α-Fe到γ′-Fe 4N的相变，同时温度低于铁的结晶温度。
所得材料的VSM表征结果(图3)，可以看出，球磨后的样品Ms为208emu/g，矫顽力3.2Oe；200摄氏度退火后，Ms为188emu/g，矫顽力2.3Oe，此时根据XRD图谱计算，γ′-Fe 4N的相所占总体比例为20％左右；250摄氏度退火后，Ms为179emu/g，矫顽力1.2Oe，此时根据XRD图谱计算，γ′-Fe 4N的相所占总体比例为35％左右；300摄氏度退火后，Ms为155emu/g，矫顽力0.7Oe，根据XRD图谱计算，γ′-Fe 4N的相所占总体比例为75％左右。
实施例3：
参照实施例1，将球和铁粉材料的重量比由10：1替换为30：1，其他条件不变，制备得到铁氮材料。所得铁氮材料的磁性能与实施例1所得材料相近，产量约为实施例1中材料的 30％左右。
对照例1：
参照实施例1，将氮源由液氮替换为氨气，其他条件不变，制备得到铁氮材料。
所得铁氮材料的含氮率为6％，Ms为185emu/g，矫顽力为10Oe，电阻率25μΩ·m，所得γ′-Fe 4N的相所占总体比例为10％左右，可以看出，γ′-Fe 4N的相比例偏低，导致制备材料整体性能与纯铁类似。

Claims (15)

  1. 一种γ'-Fe 4N软磁材料的制备方法，其特征在于，所述方法是利用液氮作为氮源，结合球磨、退火工艺进行制备，包括：
    (1)铁原料放入球磨机中，球和铁原料的重量比为5：1～20：1，在球磨罐中冲入液氮，开始球磨；
    (2)然后加热250℃～300℃退火，即得γ'-Fe 4N软磁材料。
  2. 根据权利要求1所述的方法，其特征在于，所述球和铁原料的重量比为10：1。
  3. 根据权利要求1所述的方法，其特征在于，所述步骤(1)中铁原料包括铁粉，铁粉的颗粒直径为10纳米至1000微米，纯度不低于90％。
  4. 一种γ'-Fe 4N软磁材料的制备方法，其特征在于，所述方法是利用液氮作为氮源，结合球磨、退火工艺进行制备，包括：
    (1)铁原料放入球磨机中，然后在球磨罐中冲入液氮，开始球磨；
    (2)加热退火，即得γ'-Fe 4N软磁材料。
  5. 根据权利要求4所述的方法，其特征在于，所述步骤(2)中退火的温度为200℃～350℃。
  6. 根据权利要求4所述的方法，其特征在于，所述步骤(1)中球磨时间为1h至200h。
  7. 根据权利要求4所述的方法，其特征在于，所述步骤(1)中球磨温度为-196℃～25℃。
  8. 根据权利要求4所述的方法，其特征在于，所述退火温度为250℃～300℃。
  9. 根据权利要求4所述的方法，其特征在于，所述球和铁原料的重量比为5：1～20：1。
  10. 根据权利要求4所述的方法，其特征在于，所述步骤(1)中铁原料包括铁粉，铁粉的颗粒直径为10纳米至1000微米，纯度不低于90％。
  11. 根据权利要求4所述的方法，其特征在于，所述步骤(1)中球磨机的转速为200至10000转/分钟。
  12. 根据权利要求4-11任一所述的方法，其特征在于，所述步骤(1)中球磨温度保持液氮温度-196℃。
  13. 一种γ'-Fe 4N软磁材料，其特征在于，所述γ'-Fe 4N软磁材料是利用权利要求1-11任一所述的方法制备得到的。
  14. 一种高频半导体开关中操作的变压器或电感器，其特征在于，所述变压器或电感器包含权利要求13所述的γ'-Fe 4N软磁材料。
  15. 一种功率电子器件，其特征在于，所述功率电子器件中包含权利要求13所述的γ'-Fe 4N软磁材料。
PCT/CN2018/120823 2018-12-11 2018-12-13 一种利用液氮高速球磨制备γ'-Fe4N软磁材料的方法 WO2020118599A1 (zh)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112475302A (zh) * 2020-11-16 2021-03-12 安徽省瑞峻粉末金属材料有限公司 一种超细纳米晶vn合金粉末的制备方法

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113493895A (zh) * 2020-03-19 2021-10-12 甘肃省科学院传感技术研究所 一种γ′-Fe4N磁性多孔膜的制备方法及其应用
CN113998897B (zh) * 2021-10-28 2023-11-24 杭州光学精密机械研究所 一种快速合成硫系玻璃粉体的设备
CN115116733B (zh) * 2022-07-18 2023-03-24 麦格磁电科技（珠海）有限公司 一种高频低损耗mpp软磁合金粉芯的制备方法

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6476906A (en) * 1987-09-18 1989-03-23 Nat Res Inst Metals Production of nitride
CN107396631A (zh) * 2015-01-26 2017-11-24 明尼苏达大学董事会 具有各向异性形状的铁氮化物粉末

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1202537C (zh) * 2003-07-21 2005-05-18 北京科技大学 一种用机械合金化制备钐铁氮永磁材料的方法
CN1555949A (zh) * 2004-01-08 2004-12-22 北京科技大学 一种液氮低温球磨制备纳米粉体的方法
US9242295B2 (en) * 2007-12-21 2016-01-26 The Univeristy Of Texas At Arlington Bulk nanocomposite magnets and methods of making bulk nanocomposite magnets
CN104271496A (zh) * 2011-12-15 2015-01-07 卡斯西部储备大学 不含稀土的能够转变的氮化物磁体及其制造方法
CN103131928B (zh) * 2013-02-06 2015-04-08 西南交通大学 一种具有微纳米结构的超细晶多孔铁合金的制备方法
US9581214B2 (en) * 2013-06-24 2017-02-28 The Regents Of The University Of California Semi-active isolators based on magnetorheological nanocomposites
JP2016536777A (ja) * 2013-06-27 2016-11-24 リージェンツ オブ ザ ユニバーシティ オブ ミネソタ 窒化鉄材料及び窒化鉄材料を含む磁石
CN104192815B (zh) * 2014-08-27 2015-08-05 山东大学 一种枝状氮化铁粉末及其制备方法

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6476906A (en) * 1987-09-18 1989-03-23 Nat Res Inst Metals Production of nitride
CN107396631A (zh) * 2015-01-26 2017-11-24 明尼苏达大学董事会 具有各向异性形状的铁氮化物粉末

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112475302A (zh) * 2020-11-16 2021-03-12 安徽省瑞峻粉末金属材料有限公司 一种超细纳米晶vn合金粉末的制备方法
CN112475302B (zh) * 2020-11-16 2023-02-24 安徽省瑞峻粉末金属材料有限公司 一种超细纳米晶vn合金粉末的制备方法

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