CN105603296A - Rare earth Fe-based electromagnetic shielding material and preparation method thereof - Google Patents
Rare earth Fe-based electromagnetic shielding material and preparation method thereof Download PDFInfo
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- 239000000463 material Substances 0.000 title claims abstract description 42
- 238000002360 preparation method Methods 0.000 title claims abstract description 29
- 229910052761 rare earth metal Inorganic materials 0.000 title claims abstract description 22
- 150000002910 rare earth metals Chemical class 0.000 title claims abstract description 21
- 229910045601 alloy Inorganic materials 0.000 claims abstract description 56
- 239000000956 alloy Substances 0.000 claims abstract description 56
- 238000010438 heat treatment Methods 0.000 claims abstract description 41
- 238000000498 ball milling Methods 0.000 claims abstract description 33
- 238000010521 absorption reaction Methods 0.000 claims abstract description 25
- 239000012188 paraffin wax Substances 0.000 claims abstract description 20
- 238000000034 method Methods 0.000 claims abstract description 18
- 238000010791 quenching Methods 0.000 claims abstract description 17
- 238000005496 tempering Methods 0.000 claims abstract description 13
- 229910052799 carbon Inorganic materials 0.000 claims abstract description 12
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims abstract description 10
- 230000000171 quenching effect Effects 0.000 claims abstract description 10
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 claims abstract description 6
- 230000007797 corrosion Effects 0.000 claims abstract description 6
- 238000005260 corrosion Methods 0.000 claims abstract description 6
- 229910052779 Neodymium Inorganic materials 0.000 claims abstract description 5
- 239000007788 liquid Substances 0.000 claims abstract description 5
- 229910052757 nitrogen Inorganic materials 0.000 claims abstract description 5
- 229910052786 argon Inorganic materials 0.000 claims abstract description 3
- 239000002994 raw material Substances 0.000 claims abstract description 3
- 239000000843 powder Substances 0.000 claims description 47
- 238000002310 reflectometry Methods 0.000 claims description 22
- 238000005516 engineering process Methods 0.000 claims description 20
- 230000035699 permeability Effects 0.000 claims description 19
- 239000000203 mixture Substances 0.000 claims description 17
- 238000002844 melting Methods 0.000 claims description 16
- 230000008018 melting Effects 0.000 claims description 16
- 238000001514 detection method Methods 0.000 claims description 10
- 238000012545 processing Methods 0.000 claims description 10
- 239000006096 absorbing agent Substances 0.000 claims description 9
- 239000011248 coating agent Substances 0.000 claims description 9
- 238000000576 coating method Methods 0.000 claims description 9
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 8
- 239000002356 single layer Substances 0.000 claims description 8
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 8
- 238000009413 insulation Methods 0.000 claims description 2
- QCWXUUIWCKQGHC-UHFFFAOYSA-N Zirconium Chemical compound [Zr] QCWXUUIWCKQGHC-UHFFFAOYSA-N 0.000 claims 1
- 239000007789 gas Substances 0.000 claims 1
- 238000007689 inspection Methods 0.000 claims 1
- 238000007670 refining Methods 0.000 claims 1
- 229910052726 zirconium Inorganic materials 0.000 claims 1
- 150000001875 compounds Chemical class 0.000 abstract description 11
- 238000003723 Smelting Methods 0.000 abstract description 8
- 230000003647 oxidation Effects 0.000 abstract description 3
- 238000007254 oxidation reaction Methods 0.000 abstract description 3
- 238000009776 industrial production Methods 0.000 abstract description 2
- 239000005457 ice water Substances 0.000 abstract 1
- MCMNRKCIXSYSNV-UHFFFAOYSA-N Zirconium dioxide Chemical compound O=[Zr]=O MCMNRKCIXSYSNV-UHFFFAOYSA-N 0.000 description 16
- 230000000694 effects Effects 0.000 description 8
- 239000011358 absorbing material Substances 0.000 description 7
- 238000005275 alloying Methods 0.000 description 7
- 239000003223 protective agent Substances 0.000 description 7
- 238000012360 testing method Methods 0.000 description 7
- 239000002131 composite material Substances 0.000 description 6
- 238000011056 performance test Methods 0.000 description 6
- 238000004519 manufacturing process Methods 0.000 description 5
- 238000011160 research Methods 0.000 description 4
- 229910000859 α-Fe Inorganic materials 0.000 description 3
- 238000011161 development Methods 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 2
- 239000003595 mist Substances 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 229920000049 Carbon (fiber) Polymers 0.000 description 1
- 208000027418 Wounds and injury Diseases 0.000 description 1
- 230000002745 absorbent Effects 0.000 description 1
- 239000002250 absorbent Substances 0.000 description 1
- 239000003963 antioxidant agent Substances 0.000 description 1
- 230000003078 antioxidant effect Effects 0.000 description 1
- 235000006708 antioxidants Nutrition 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- -1 by Nd:10.5% Substances 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- 239000006229 carbon black Substances 0.000 description 1
- 239000004917 carbon fiber Substances 0.000 description 1
- 239000002134 carbon nanofiber Substances 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 238000004590 computer program Methods 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 230000006378 damage Effects 0.000 description 1
- 230000007812 deficiency Effects 0.000 description 1
- 201000010099 disease Diseases 0.000 description 1
- 208000037265 diseases, disorders, signs and symptoms Diseases 0.000 description 1
- 230000004064 dysfunction Effects 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
- 238000000227 grinding Methods 0.000 description 1
- 208000014674 injury Diseases 0.000 description 1
- 230000010354 integration Effects 0.000 description 1
- 239000006247 magnetic powder Substances 0.000 description 1
- 230000005415 magnetization Effects 0.000 description 1
- 230000003211 malignant effect Effects 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000003801 milling Methods 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 238000004088 simulation Methods 0.000 description 1
- 238000011282 treatment Methods 0.000 description 1
Classifications
-
- 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
-
- B22F1/0003—
-
- 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
-
- 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
- C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
- C21D1/18—Hardening; Quenching with or without subsequent tempering
-
- 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
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- 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
- C22C38/004—Very low carbon steels, i.e. having a carbon content of less than 0,01%
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N22/00—Investigating or analysing materials by the use of microwaves or radio waves, i.e. electromagnetic waves with a wavelength of one millimetre or more
-
- 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
- H01F1/058—Alloys characterised by their composition containing rare earth metals and magnetic transition metals, e.g. SmCo5 and IVa elements, e.g. Gd2Fe14C
-
- 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
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- Chemical & Material Sciences (AREA)
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- Life Sciences & Earth Sciences (AREA)
- Thermal Sciences (AREA)
- Electromagnetism (AREA)
- Inorganic Chemistry (AREA)
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Abstract
The invention discloses a rare earth Fe-based electromagnetic shielding material and a preparation method thereof. The alloy comprises 10.5% of Nd, 81.6-89.5% of Fe and 0.0-7.9% of C in terms of atomic percent, and is prepared according to the following process: taking Nd, Fe and C with the purities of larger than or equal to 99.90% as raw materials, smelting in the protection of argon, performing uniform heat treatment to the alloy in vacuum at 800-1050 DEG C, quenching by using ice water/liquid nitrogen, performing ball milling after mechanically crushing, and performing tempering heat treatment at 50-300 DEG C to prepare a sample. The NdFeC electromagnetic shielding material has relatively excellent microwave absorbing property within a microwave band of 2-18GHz; when an alloy micropowder/paraffin compound has the thickness 1.8mm, the minimum absorption peak thereof can reach about -16.8dB; the electromagnetic shielding material has high microwave absorbing efficiency within the microwave band of 2-18GHz, a wide microwave absorbing band, high temperature stability and low economic cost, and has certain oxidation resistance and corrosion resistance; the electromagnetic shielding material is simple in preparation process, low in economic cost, and suitable for industrial production.
Description
Technical field
The invention belongs to rare earth material field, be specifically related to a kind of rare earth Fe base electromagnetic screen material and preparation method thereof.
Background technology
Along with scientific and technological development, automobile, electronics, communication, computer and electrical equipment enter people's life, space in a large numberArtificial electromagnetic energy is annual increases by 7%～14%, and the electromagnetic wave that a large amount of electronic equipments discharge is full of space, and electronic product existsBring simultaneously easily, the person and environment are also being produced to invisible injury, and electromagnetic interference, often easily cause establishingStandby control is not normal, information misinformation, thus aircraft navigation error causes heavy losses to human society, meanwhile also may bring outThe various malignant diseases of human body and dysfunction, therefore the research of electromagnetic shielding material is more and more subject to people's attention.
Magnetic electromagnetic shielding material is research at present and answers a class with the most use, plays most important in social developmentEffect, be closely related with the every aspect of informationization, automation, electromechanical integration, national defence, national economy.
Material with carbon element taking carbon fiber, carbon black, CNT and carbon nano-fiber as representative is because form is various, as structureThe wave absorbing agent of absorbing material has had a large amount of research, but its complicated process of preparation, and economic performance is poor, fails to obtain industryChange and produce.
Ferrite is as traditional absorbing material, and the density of existence is large, absorption band is narrow and the shortcoming such as poor heat stability is madeBecome it to be unsuitable for practical application.
Magnetic metal micro mist absorbent have that microwave magnetic permeability is higher, Curie temperature is higher and preparation method more etc. excellentPoint. Thereby alloy magnetic powder has very open development space and prospect in microwave absorbing material application. Inhale ripple with ferriteMaterial is compared, and magnetic metal absorbing material is because its crystal structure is fairly simple, there is no in ferrite magnetic between magnetic time gridCancelling out each other of square, so generally its saturation magnetization is higher than ferrite, larger at the magnetic conductivity of microwave section. ThisOutward, electromagnetic wave absorbing material temperature stability in the situation that handling anti-oxidant problem well is good, and Curie temperature reaches 77OK.
Fe output in industrial production is large, and therefore good economy performance is studied Fe base alloy powder and had important production practicesMeaning, has unique character so rare earth element has very high magnetocrystalline anisotropy at aspects such as electricity, light, magnetic, is groundStudy carefully scholar's great attention, C material is because having excellent conduction and dielectric properties, and low-density is corrosion-resistant, just can by low consumptionObtain high electromagnetic wave attenuation coefficient, research is added rare earth and C material for improving absorbing property tool in Fe base alloy powderThere is feasibility.
Current material Microwave Absorption Properties in 2～18GHz microwave band is bad, and absorption band is narrow, and temperature stability is poor,Corrosion resistance is poor, and wave absorbing efficiency is low.
The method of existing preparation, complicated process of preparation, production cost are high, are not suitable for suitability for industrialized production.
Summary of the invention
For the deficiency of above-mentioned technology, a kind of rare earth Fe of the present invention base electromagnetic screen material and preparation method thereof, this materialIn 2～18GHz microwave band, have good Microwave Absorption Properties, wave absorbing efficiency is high, and absorption band is wide, and financial cost is low, temperatureDegree good stability and there is the microwave absorption product of certain oxidation resistance and decay resistance; The method has preparation technology's letterThe feature of list, low, the applicable suitability for industrialized production of financial cost.
The technical scheme that realizes the object of the invention is:
A kind of rare earth Fe base electromagnetic screen material, the atomic percent of its materials and consumption is Nd:10.5%, Fe:81.6～89.5%, C:0.0～7.9% optimum value
Above-mentioned rare earth Fe base electromagnetic screen material preparation method, comprises following steps:
1) batching; Taking Nd, the Fe of purity >=99.90%, C as raw material, by Nd:10.5%, Fe:81.6～89.5%, C:The stoichiometric equation batching of 0.0～7.9% atomic percent;
2) by step 1) in batching in non-consumable arc furnace, carry out alloying smelting;
3) melted alloy is sealed in to the homogenising heat treatment 2～15 of carrying out 800～1050 DEG C in vitreosil pipeMy god;
4) by step 3) in alloy after homogenising heat treatment in mixture of ice and water (liquid nitrogen), carry out quenching technical processing;
5) by quench after alloy coarse crushing after ball milling powder process;
6) by step 5) in alloy powder after ball milling carry out tempering heat treatment;
7) electromagnetic parameter and the reflectivity R of detection finished product;
8) obtain having absorption band wide, temperature stability is good, a kind of rare earth Fe base electro-magnetic screen that corrosion resistance is goodMaterial.
Step 2) in, by step 1) in batching, be placed in the non-consumable arc furnace of standard and carry out protecting at argon gasProtect lower melting, in order to guarantee to obtain the alloy of good uniformity, need upset melting 2～5 times.
Step 3) in, by step 2) in the alloy that obtains under vacuum atmosphere, carry out homogenising heat treatment; Described homogenisingProcessing procedure comprises insulation 2～15 days.
Step 4) in, by step 3) in alloy after homogenising heat treatment, in mixture of ice and water/liquid nitrogen, carry out quencherSkill processing.
Step 5) in, by step 4) in put into zirconia ball grinding jar after alloy coarse crushing after Quenching Treatment and carry out ball millingProcess. Described ball-milling technology zirconia ball and with the mass ratio of alloyed powder be 15:1～20:1, described ball-milling technology needs anhydrousEthanol or gasoline cook protective agent, and drum's speed of rotation 300～350r/min is set, Ball-milling Time 12～24 hours.
Step 6) in, by step 5) in the alloy powder that obtains, carry out the tempering heat treatment of 50 DEG C～300 DEG C.
Step 7) in, detect by step 5) and step 6) electromagnetic parameter and the reflectivity R of the alloy powder that obtains. Described inspectionSurvey method need to be mixed with paraffin alloy powder according to the ratio of 4:1, it is 7mm that mixture is made to external diameter, and internal diameter is 3mm,The coaxial sample of thickness between 3.0～4.0mm. Described detection adopts HP8722ES microwave vector network analyzer, surveys respectivelyAmount sample is in complex dielectric permittivity and the complex permeability of 2～18GHz frequency range. 1.0mm～the 3.0mm of described single-layer absorber
Reflectivity R adopts following formula to calculate simulation, In formulaK be propagation constant (), z be wave impedance (), wherein z0For the wave impedance of vacuum, μ0、ε0Be respectively space permeability, permittivity of vacuum and microwave absorbing coating thickness, ε ' with d" be respectively real part and the imaginary part of complex dielectric permittivity, μ ' and μ " are respectively real part and the imaginary part of complex permeability to and ε.
Experimental result:
In 2～18GHz wave band, microwave absorbing coating thickness between 1.0～3.0mm, NdFeC alloy powder/paraffin compoundReflectivity the minimum peak be all less than-5dB of magnetic micro-powder to microwave, and there is good wideband effect;
Work as Nd10.53Fe84.21C5.26When alloy powder/paraffin composite thickness is 1.8mm, to the reflectance peak of microwaveLittle reaching-16.8dB left and right, has good wideband effect, especially has good wave-absorbing effect in S-band (2～4GHz),Can be as a kind of high-performance wave-absorbing material. Nd10.53Fe84.21C5.26Powder is through 100 DEG C of heat treatments after 2 hours, when its alloyWhen micro mist/paraffin composite thickness is 3.0mm, to the reach-21.8dB of I of the absorption peak of S-band microwave left and right, when itWhen thickness is 1.0mm, the reach-13.2dB of reflectivity minimum to microwave and frequency coverage 8～15GHz frequency band of <-5dB.
Beneficial effect:
A kind of rare earth Fe of the present invention base electromagnetic screen material and preparation method thereof,
This material has good Microwave Absorption Properties in 2～18GHz microwave band, and absorption band is wide, temperature stabilizationProperty is good, and financial cost is low, has good oxidation resistance and corrosion resistance, in electromagnetic wave absorbing material; The method hasPreparation technology is simple, financial cost is low, be applicable to suitability for industrialized production.
Brief description of the drawings
Fig. 1 is preparation technology's flow chart of the present invention;
Fig. 2 is Nd10.53Fe89.47Electromagnetic shielding material test result figure;
Fig. 3 is Nd10.53Fe84.21C5.26Electromagnetic shielding material test result figure;
Fig. 4 is Nd10.53Fe81.58C7.89Electromagnetic shielding material test result figure.
Fig. 5 is Nd10.53Fe84.21C5.2650 DEG C of heat treatment electromagnetic shielding material test result figure after 2 hours.
Fig. 6 is Nd10.53Fe84.21C5.26100 DEG C of heat treatment electromagnetic shielding material test result figure after 2 hours.
Fig. 7 is Nd10.53Fe84.21C5.26300 DEG C of heat treatment electromagnetic shielding material test result figure after 2 hours.
Detailed description of the invention
Below in conjunction with accompanying drawing, the present invention is further elaborated, but be not limitation of the invention
Embodiment 1:
As shown in Figure 1:
Preparation Nd10.53Fe89.47The concrete implementation step of (atomic percent) is:
1) by purity Nd, Fe, C material all >=99.90%, match well by the stoichiometry of Nd:10.53%Fe:89.47%Material;
2) by step 1) in batching in non-consumable arc furnace, carry out alloying smelting, for ensure melting evenlyProperty, the melting 2～5 times of need repeatedly overturning;
3) melted alloy is sealed in to the homogenising heat treatment 10 days of carrying out 900 DEG C in vitreosil pipe;
4) by step 3) in alloy after homogenising heat treatment in mixture of ice and water, carry out quenching technical processing;
5) by quench after alloy coarse crushing after ball milling powder process; Described ball-milling technology zirconia ball and with the matter of alloyed powderAmount is than being 20:1, and described ball-milling technology needs absolute ethyl alcohol or gasoline to cook protective agent, and drum's speed of rotation 300r/min is set, ball milling20 hours time;
6) by step 5) in alloy powder after ball milling carry out tempering heat treatment;
7) electromagnetic parameter and the reflectivity R of detection finished product; Mix in the ratio of alloy powder: paraffin=4:1 (mass ratio),Make external diameter and internal diameter and be respectively 7mm and 3mm, thickness, at the coaxial sample of 3.0～4.0mm left and right, adopts HP8722ES microwaveVector network analyzer is measured respectively complex permeability, the complex dielectric permittivity of sample in 2～18GHz frequency range. Then adopt following formula meterCalculation simulates single-layer absorber and is respectively at thickness the reflectivity R of 1.0mm, 1.2mm, 1.4mm, 1.8mm, 2.5mm, 3.0mm.
K in formula be propagation constant (), z be wave impedance (), wherein z0For the wave impedance of vacuum, μ0、ε0Be respectively space permeability, vacuum with dDielectric constant and microwave absorbing coating thickness, " be respectively real part and the imaginary part of complex dielectric permittivity, μ ' and μ " are respectively multiple magnetic conductance for ε ' and εThe real part of rate and imaginary part.
The performance test results:
Fig. 2 is Nd10.53Fe89.47Alloy powder/paraffin compound thickness in 2～18GHz microwave band is respectivelyReflectivity when 1.0mm, 1.2mm, 1.4mm, 1.8mm, 2.5mm, 3.0mm. From figure, can obtain: in the time that 1.0～3.0mm is thick, 2In～18GHz microwave band, all reach-5dB of reflectance peak, and < frequency range of-5dB is wider, has good wideband effect.In the time that thickness is 3.0mm, this alloy powder/paraffin compound has certain microwave absorption effect at s wave band (2～4GHz);At the reach-7dB of reflectivity minimum peak of 2.5GHz frequency place, in the time that being 1.0mm, thickness there is wider frequency range effect, <-5dB'sFrequency range reaches 5.0GHz.
Embodiment 2:
Preparation Nd10.53Fe84.21C5.26The concrete implementation step of (atomic percent) is:
1) by purity Nd, Fe, C material all >=99.90%, by the chemistry of Nd:10.53%Fe:84.21%C:5.26%Metering is than batching;
2) by step 1) in batching in non-consumable arc furnace, carry out alloying smelting, for ensure melting evenlyProperty, the melting 2～5 times of need repeatedly overturning;
3) melted alloy is sealed in to the homogenising heat treatment 2 days of carrying out 800 DEG C in vitreosil pipe;
4) by step 3) in alloy after homogenising heat treatment in mixture of ice and water, carry out quenching technical processing;
5) by quench after alloy coarse crushing after ball milling powder process; Described ball-milling technology zirconia ball and with the matter of alloyed powderAmount is than being 15:1, and described ball-milling technology needs absolute ethyl alcohol or gasoline to cook protective agent, and drum's speed of rotation 350r/min is set, ball milling24 hours time;
6) by step 5) in alloy powder after ball milling carry out tempering heat treatment;
7) electromagnetic parameter and the reflectivity R of detection finished product; Mix in the ratio of alloy powder: paraffin=4:1 (mass ratio),Make external diameter and internal diameter and be respectively 7mm and 3mm, thickness, at the coaxial sample of 3.0～4.0mm left and right, adopts HP8722ES microwaveVector network analyzer is measured respectively complex permeability, the complex dielectric permittivity of sample in 2～18GHz frequency range. Then adopt following formula meterCalculation simulates single-layer absorber and is respectively at thickness the reflectivity R of 1.0mm, 1.2mm, 1.4mm, 1.8mm, 2.5mm, 3.0mm.
K in formula be propagation constant (), z be wave impedance (), wherein z0For the wave impedance of vacuum, μ0、ε0Be respectively space permeability, vacuum with dDielectric constant and microwave absorbing coating thickness, " be respectively real part and the imaginary part of complex dielectric permittivity, μ ' and μ " are respectively multiple magnetic conductance for ε ' and εThe real part of rate and imaginary part.
The performance test results:
Fig. 3 is Nd10.53Fe84.21C5.26Powder/paraffin compound thickness in 2～18GHz microwave band is respectivelyReflectivity when 1.0mm, 1.2mm, 1.4mm, 1.8mm, 2.5mm, 3.0mm. From figure, can obtain: in all thickness, reflectionAll be less than-10dB of rate peak value, and there is good wideband effect. In the time that thickness is 3.0mm, in 2.9GHz place reflectivity smallest peaksCan reach-12.8dB of value has wider frequency range effect in the time that thickness is 1.0mm, and the frequency range of <-5dB reaches 6GHz.
Embodiment 3:
Preparation Nd10.53Fe81.58C7.89The concrete implementation step of (atomic percent):
1) by purity Nd, Fe, C material all >=99.90%, by the chemistry of Nd:10.53%Fe:81.58%C:7.89%Metering is than batching;
2) by step 1) in batching in non-consumable arc furnace, carry out alloying smelting, for ensure melting evenlyProperty, the melting 2～5 times of need repeatedly overturning;
3) melted alloy is sealed in to the homogenising heat treatment 15 days of carrying out 1050 DEG C in vitreosil pipe;
4) by step 3) in alloy after homogenising heat treatment in liquid nitrogen, carry out quenching technical processing;
5) by quench after alloy coarse crushing after ball milling powder process; Described ball-milling technology zirconia ball and with the matter of alloyed powderAmount is than being 20:1, and described ball-milling technology needs absolute ethyl alcohol or gasoline to cook protective agent, and drum's speed of rotation 300r/min is set, ball milling24 hours time;
6) by step 5) in alloy powder after ball milling carry out tempering heat treatment;
7) electromagnetic parameter and the reflectivity R of detection finished product; Mix in the ratio of alloy powder: paraffin=4:1 (mass ratio),Make external diameter and internal diameter and be respectively 7mm and 3mm, thickness, at the coaxial sample of 3.0～4.0mm left and right, adopts HP8722ES microwaveVector network analyzer is measured respectively complex permeability, the complex dielectric permittivity of sample in 2～18GHz frequency range. Then adopt following formula meterCalculation simulates single-layer absorber and is respectively at thickness the reflectivity R of 1.0mm, 1.2mm, 1.4mm, 1.8mm, 2.5mm, 3.0mm.
K in formula be propagation constant (), z be wave impedance (), wherein z0For the wave impedance of vacuum, μ0、ε0Be respectively space permeability, vacuum with dDielectric constant and microwave absorbing coating thickness, " be respectively real part and the imaginary part of complex dielectric permittivity, μ ' and μ " are respectively multiple magnetic conductance for ε ' and εThe real part of rate and imaginary part.
The performance test results:
Fig. 4 is Nd10.53Fe81.58C7.89Powder/paraffin compound thickness in 2～18GHz microwave band is respectivelyReflectivity when 1.0mm, 1.2mm, 1.4mm, 1.8mm, 2.0mm, 2.5mm. From figure, can obtain: in the middle of all thickness, compoundAll be less than-5dB of the absorption peak of thing, has certain Microwave Absorption Properties; In the time that composite thickness is 1.8mm, at 3.2GHzReach-the 5.9dB of minimum reflectance peak value of frequency place left and right, frequency bandwidth (<-5dB) has reached 1.0GHz, has one in low-frequency rangeDetermine the material of absorbing property.
Embodiment 4:
Preparation tempering heat treatment Nd10.53Fe84.21C5.26The concrete implementation step of (atomic percent) powder is:
2) by step 1) in batching in non-consumable arc furnace, carry out alloying smelting, for ensure melting evenlyProperty, the melting 2～5 times of need repeatedly overturning;
3) melted alloy is sealed in to the homogenising heat treatment 2 days of carrying out 800 DEG C in vitreosil pipe;
4) by step 3) in alloy after homogenising heat treatment in mixture of ice and water, carry out quenching technical processing;
5) by quench after alloy coarse crushing after ball milling powder process; Described ball-milling technology zirconia ball and with the matter of alloyed powderAmount is than being 15:1, and described ball-milling technology needs absolute ethyl alcohol or gasoline to cook protective agent, and drum's speed of rotation 350r/min is set, ball milling24 hours time;
6) by step 5) in alloy powder after ball milling carry out 50 DEG C of tempering heat treatment 2 hours;
7) electromagnetic parameter and the reflectivity R of detection finished product; Mix in the ratio of alloy powder: paraffin=4:1 (mass ratio),Make external diameter and internal diameter and be respectively 7mm and 3mm, thickness, at the coaxial sample of 3.0～4.0mm left and right, adopts HP8722ES microwaveVector network analyzer is measured respectively complex permeability, the complex dielectric permittivity of sample in 2～18GHz frequency range. Then adopt following formula meterCalculation simulates single-layer absorber and is respectively at thickness the reflectivity R of 1.0mm, 1.2mm, 1.4mm, 1.8mm, 2.5mm, 3.0mm.
K in formula be propagation constant (), z be wave impedance (), wherein z0For the wave impedance of vacuum, μ0、ε0Be respectively space permeability, vacuum with dDielectric constant and microwave absorbing coating thickness, " be respectively real part and the imaginary part of complex dielectric permittivity, μ ' and μ " are respectively multiple magnetic conductance for ε ' and εThe real part of rate and imaginary part.
The ratio mixing of product test: alloy powder: paraffin=4:1 (mass ratio), makes external diameter and internal diameter is respectively 7mmAnd 3mm, thickness is at the coaxial sample of 3.0～4.0mm left and right, and measurements and calculations, with embodiment 1, are then used computer program mouldDraw up the reflectivity that thickness is respectively 1.0mm, 1.2mm, 1.4mm, 1.8mm, 2.5mm, 3.0mm.
The performance test results:
Fig. 5 is Nd10.53Fe84.21C5.26After 50 DEG C of heat treatments, powder/paraffin compound is thick in 2～18GHz microwave bandReflectivity when degree is respectively 1.0mm, 1.2mm, 1.4mm, 1.8mm, 2.5mm, 3.0mm. From figure, can obtain: work as at all thicknessIn, be all less than-10dB of the absorption peak of compound, has good Microwave Absorption Properties; In the time that composite thickness is 3.0mm,In the reach-13.8dB of minimum reflectance peak value of 2.9GHz frequency place left and right, frequency bandwidth (<-10dB) has reached 0.8GHz, lowFrequency range has good absorbing property. In the time that its thickness is 1.0mm, frequency bandwidth (<-5dB) reaches 6.5GHz, has betterFrequency range characteristic and Microwave Absorption Properties.
Embodiment 5:
Preparation tempering heat treatment Nd10.53Fe84.21C5.26The concrete implementation step of (atomic percent) powder is:
2) by step 1) in batching in non-consumable arc furnace, carry out alloying smelting, for ensure melting evenlyProperty, the melting 2～5 times of need repeatedly overturning;
3) melted alloy is sealed in to the homogenising heat treatment 2 days of carrying out 900 DEG C in vitreosil pipe;
4) by step 3) in alloy after homogenising heat treatment in mixture of ice and water, carry out quenching technical processing;
5) by quench after alloy coarse crushing after ball milling powder process; Described ball-milling technology zirconia ball and with the matter of alloyed powderAmount is than being 20:1, and described ball-milling technology needs absolute ethyl alcohol or gasoline to cook protective agent, and drum's speed of rotation 350r/min is set, ball milling24 hours time;
6) by step 5) in alloy powder after ball milling carry out 100 DEG C of tempering heat treatment;
7) electromagnetic parameter and the reflectivity R of detection finished product; Mix in the ratio of alloy powder: paraffin=4:1 (mass ratio),Make external diameter and internal diameter and be respectively 7mm and 3mm, thickness, at the coaxial sample of 3.0～4.0mm left and right, adopts HP8722ES microwaveVector network analyzer is measured respectively complex permeability, the complex dielectric permittivity of sample in 2～18GHz frequency range. Then adopt following formula meterCalculation simulates single-layer absorber and is respectively at thickness the reflectivity R of 1.0mm, 1.2mm, 1.4mm, 1.8mm, 2.5mm, 3.0mm.
K in formula be propagation constant (), z be wave impedance (), wherein z0For the wave impedance of vacuum, μ0、ε0Be respectively space permeability, vacuum with dDielectric constant and microwave absorbing coating thickness, " be respectively real part and the imaginary part of complex dielectric permittivity, μ ' and μ " are respectively multiple magnetic conductance for ε ' and εThe real part of rate and imaginary part.
The performance test results:
Fig. 6 is Nd10.53Fe84.21C5.26After 100 DEG C of heat treatments, powder/paraffin compound is in 2～18GHz microwave bandReflectivity when thickness is respectively 1.0mm, 1.2mm, 1.4mm, 1.8mm, 2.5mm, 3.0mm. From figure, can obtain: at all thicknessIn the middle of, be all less than-10dB of the absorption peak of compound, has good Microwave Absorption Properties; When composite thickness is 3.0mmTime, in the reach-21.8dB of minimum reflectance peak value of 3.1GHz frequency place left and right, frequency bandwidth (<-10dB) has reached 1.0GHz,There is good absorbing property in low-frequency range. In the time that its thickness is 1.0mm, frequency bandwidth <-5dB reaches 8GHz, frequency bandwidth<-10dB has also reached 2GHz, has good frequency range characteristic and Microwave Absorption Properties.
Embodiment 6:
Preparation tempering heat treatment Nd10.53Fe84.21C5.26The concrete implementation step of (atomic percent) powder is:
2) by step 1) in batching in non-consumable arc furnace, carry out alloying smelting, for ensure melting evenlyProperty, the melting 2～5 times of need repeatedly overturning;
3) melted alloy is sealed in to the homogenising heat treatment 2 days of carrying out 900 DEG C in vitreosil pipe;
4) by step 3) in alloy after homogenising heat treatment in mixture of ice and water, carry out quenching technical processing;
5) by quench after alloy coarse crushing after ball milling powder process; Described ball-milling technology zirconia ball and with the matter of alloyed powderAmount is than being 20:1, and described ball-milling technology needs absolute ethyl alcohol or gasoline to cook protective agent, and drum's speed of rotation 350r/min is set, ball milling24 hours time;
6) by step 5) in alloy powder after ball milling carry out 300 DEG C of tempering heat treatment;
7) electromagnetic parameter and the reflectivity R of detection finished product; Mix in the ratio of alloy powder: paraffin=4:1 (mass ratio),Make external diameter and internal diameter and be respectively 7mm and 3mm, thickness, at the coaxial sample of 3.0～4.0mm left and right, adopts HP8722ES microwaveVector network analyzer is measured respectively complex permeability, the complex dielectric permittivity of sample in 2～18GHz frequency range. Then adopt following formula meterCalculation simulates single-layer absorber and is respectively at thickness the reflectivity R of 1.0mm, 1.2mm, 1.4mm, 1.8mm, 2.5mm, 3.0mm.
K in formula be propagation constant (), z be wave impedance (), wherein z0For the wave impedance of vacuum, μ0、ε0Be respectively space permeability, vacuum with dDielectric constant and microwave absorbing coating thickness, " be respectively real part and the imaginary part of complex dielectric permittivity, μ ' and μ " are respectively multiple magnetic conductance for ε ' and εThe real part of rate and imaginary part.
The performance test results:
Fig. 7 is Nd10.53Fe84.21C5.26After 300 DEG C of heat treatments, powder/paraffin compound is in 2～18GHz microwave bandReflectivity when thickness is respectively 1.0mm, 1.2mm, 1.4mm, 1.8mm, 2.5mm, 3.0mm. From figure, can obtain: at all thicknessIn the middle of, be all less than-5dB of the absorption peak of compound, has good Microwave Absorption Properties; In the time that composite thickness is 3.0mm,In the reach-15.7dB of minimum reflectance peak value of 3.1GHz frequency place left and right, frequency bandwidth (<-10dB) has reached 1.0GHz, lowFrequency range has good absorbing property. In the time that its thickness is 1.0mm, frequency bandwidth <-5dB reaches 8GHz, minimal absorption peak valueAlso reached-10dB, there is good frequency range characteristic and Microwave Absorption Properties.
Claims (10)
1. a rare earth Fe base electromagnetic screen material, is characterized in that: described materials are Nd, Fe, C; The atomic percent of consumptionFor: Nd:10.5%, Fe:81.6～89.5%, C:0.0～7.9%.
2. a rare earth Fe base electromagnetic screen material preparation method, it comprises and is prepared as follows step:
1) batching;
2) melting;
3) homogenising heat treatment;
4) quenching technical processing
5) ball milling powder process;
6) tempering heat treatment;
7) electromagnetic parameter and the reflectivity R of inspection manufactured goods or detection finished product;
8) obtain having absorption band wide, temperature stability is good, a kind of rare earth Fe base electromagnetic screen material that corrosion resistance is good.
3. rare earth Fe base electromagnetic screen material preparation method according to claim 2, is characterized in that step 1) in pureNd, Fe, the C of degree >=99.90% are raw material, by the chemistry of Nd:10.5Fe:81.6～89.5C:0.0～7.9 atomic percentAmount formula batching.
4. rare earth Fe base electromagnetic screen material preparation method according to claim 2, is characterized in that step 2) in,In the non-consumable arc furnace of standard, need to carry out under argon gas atmosphere protection, in order to ensure the uniformity of alloy, need upset melting 2～5 times.
5. rare earth Fe base electromagnetic screen material preparation method according to claim 2, is characterized in that step 3) in, moltenThe alloy that refining obtains carries out homogenising heat treatment under vacuum under atmosphere; Described homogenising processing procedure comprises insulation 2～15 days.Homogenising heat treatment temperature is advisable with 800～1050 DEG C, and the time is better with 2～15 days.
6. rare earth Fe base electromagnetic screen material preparation method according to claim 2, is characterized in that step 4) in, quenchIgnition technique need to be with mixture of ice and water or liquid nitrogen.
7. rare earth Fe base electromagnetic screen material preparation method according to claim 2, is characterized in that step 5) in, oxygenChange zirconium ball and with the mass ratio of alloyed powder be 15:1～20:1, do in protectant situation ball milling system at absolute ethyl alcohol or gasolinePowder, the time of ball milling is 12～24h, drum's speed of rotation is 300～350r/min.
8. rare earth Fe base electromagnetic screen material preparation method according to claim 2, is characterized in that step 6) in, ballAfter mill, alloyed powder powder is dried, then carry out 50～300 DEG C of heat treatments, alloyed powder is placed in to container and heat-treats, heat treatmentTime be 2 hours.
9. rare earth Fe base electromagnetic screen material preparation method according to claim 2, is characterized in that step 7) in, inspectionThe electromagnetic parameter and the reflectivity R that survey finished product, mix with paraffin NdFeC alloy powder according to the ratio of 4:1, mixture is madeExternal diameter is 7mm, and internal diameter is 3mm, the coaxial sample of thickness between 3.0～4.0mm; Described detection adopts HP8722ES microwave to vowAmount Network Analyzer, measures respectively complex dielectric permittivity and the complex permeability of sample in 2～18GHz frequency range, then adopts following formula meterCalculation simulates the reflectivity R of single-layer absorber under 1.0～3.0mm thickness,
K in formula is propagation constantZ is wave impedanceWherein z0For the wave impedance of vacuum, μ0、ε0Be respectively space permeability, permittivity of vacuum and microwave absorbing coating thickness with d, ε ' and" be respectively real part and the imaginary part of complex dielectric permittivity, μ ' and μ " are respectively real part and the imaginary part of complex permeability to ε.
10. according to the preparation technology described in claim 2～9, prepare needed alloy powder.
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN107385318A (en) * | 2017-06-12 | 2017-11-24 | 江西理工大学 | A kind of NdFe alloys electromagnetic wave absorbing material and preparation method thereof |
| CN111380928A (en) * | 2020-03-30 | 2020-07-07 | 北京工业大学 | Reflection characteristic-based method for detecting wave-absorbing performance of carbon nanotube wave-absorbing material |
| CN111431239A (en) * | 2020-04-20 | 2020-07-17 | 蓝沛光线（上海）电子科技有限公司 | Wireless charging module and preparation method thereof |
| CN112077298A (en) * | 2020-08-20 | 2020-12-15 | 贺州学院 | ErFe @ GO composite microwave absorbent and preparation method thereof |
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| CN104451264A (en) * | 2014-12-09 | 2015-03-25 | 桂林电子科技大学 | Laceni magnetic wave absorbing material and preparation method thereof |
| CN104846272A (en) * | 2015-05-14 | 2015-08-19 | 黄鹏腾 | Nd and La-doped iron base alloy wave absorption material |
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| CN1033494A (en) * | 1987-12-11 | 1989-06-21 | 菲利浦光灯制造公司 | The hard magnetic material made from rare earth metal, iron and carbon |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN107385318A (en) * | 2017-06-12 | 2017-11-24 | 江西理工大学 | A kind of NdFe alloys electromagnetic wave absorbing material and preparation method thereof |
| CN111380928A (en) * | 2020-03-30 | 2020-07-07 | 北京工业大学 | Reflection characteristic-based method for detecting wave-absorbing performance of carbon nanotube wave-absorbing material |
| CN111380928B (en) * | 2020-03-30 | 2022-12-02 | 北京工业大学 | Reflection characteristic-based method for detecting wave-absorbing performance of carbon nanotube wave-absorbing material |
| CN111431239A (en) * | 2020-04-20 | 2020-07-17 | 蓝沛光线（上海）电子科技有限公司 | Wireless charging module and preparation method thereof |
| CN112077298A (en) * | 2020-08-20 | 2020-12-15 | 贺州学院 | ErFe @ GO composite microwave absorbent and preparation method thereof |
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