CN103014417B - Novel (FeCo)B microwave absorbing material - Google Patents
Novel (FeCo)B microwave absorbing material Download PDFInfo
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- CN103014417B CN103014417B CN201310018707.0A CN201310018707A CN103014417B CN 103014417 B CN103014417 B CN 103014417B CN 201310018707 A CN201310018707 A CN 201310018707A CN 103014417 B CN103014417 B CN 103014417B
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Abstract
The invention discloses a novel (FeCo)B microwave absorbing material and relates to a new material used for absorbing electromagnetic waves and a preparation method of the novel (FeCo)B microwave absorbing material. The (FeCo)B microwave absorbing material comprises, by mass fraction, 47.0-50.0% of Fe, 50.0-53.0% of Co and 0.6-0.9% of B in 100%. The preparation method includes steps of (1), preparing (FeCo)B alloy ingot uniform in components by means of vacuum induction smelting; (2), rapidly quenching by means of melt overflow method to prepare a thin belt with the thickness smaller than 15 micrometers; (3), manufacturing the thin belt into powder with grain diameter of 100-150 micrometers for 0.1-0.2 hour; and (4), mechanically grinding the powder, wherein the linear velocity of a cooling roller is 30-50m/s, vacuum degree ranges from 1-2X10<-3>Pa, ratio of grinding powder to the material is 40:1, and ball grinding time ranges from 6-12 hours. The novel (FeCo)B microwave absorbing material and the preparation method thereof have the advantages that at low frequency ranging from 2-8GHz, the novel (FeCo)B microwave absorbing material having higher magnetic conductivity and magnetic loss, Curie temperature higher than 800 DEG C and the thickness of 1.8mm has microwave absorbing performance which can be up to -11.5dB, and is wide in application prospect at high-temperature low frequency.
Description
Technical field
The invention provides a kind of novel (FeCo) B microwave absorbing material, relate to a kind of novel material and method thereof that is applied to absorb electromagnetic microwave, in 2～8GHz band limits, there is excellent absorbing property, in high temperature range, be with a wide range of applications, belong to microwave absorbing field simultaneously.
Background technology
Along with the high speed development of modern science and technology especially electronic industrial technology, electromagnetic radiation, also in the living space that is constantly flooded with people, has caused serious electromagnetic pollution, causes the concern of countries in the world.In 21 century, Contamination of Electromagnetic Wave will become the premier physical contamination of ecotope.At military aspect, along with the modern times such as radar, millimeter wave, infrared, laser, multispectral and sound wave are surveyed and guidance technology is widely used in weapons system, make the hit rate of weapon improve 1～2 order of magnitude.Therefore, stealthy technique is as the effective means that improves the stealthy existence of weapons system, prominent anti-and overall fighting efficiency, be subject to the great attention of each military power of the world, and be called as up-to-date three large technological contributions in military science together with laser weapon, cruise missile.Absorbing material is basis in stealthy technique and crucial, so the development of novel wave-absorbing material and Application and Development are subject to the great attention of various countries more.Open source literature about this respect in prior art can be with reference to CN101232799A, CN102206081A, CN101329921A, CN1338760, CN102031446A.
From wave-absorbing mechanism, absorbing material is mainly divided into dielectric consumption type and magnetic loss type, mainly comprises Ferrite Material, electroconductive magnetic fiber, silicon carbide, nanocrystalline material, metal magnetic powder.Dielectric loss shaped material, as graphite, silicon carbide etc., has high specific inductivity and larger dielectric loss angle, with the electronic polarization of medium or interface, decays and carrys out electromagnetic wave absorption; Magnetic loss shaped material is as ferrite, metal magnetic powder, nanometer stealthy materials, and absorption mechanism is mainly ferromagnetic resonance absorption, has larger magnetic loss angle, with eddy-current loss, magnetic hysteresis loss, the residual loss mechanism hertzian wave of decaying, reaches the effect of inhaling ripple.
Along with after people recognize the importance of microwave absorbing material, people just start to carry out the research and discovery of related fields, have formed relevant technology and intellecture property.
On July 30th, 2008, Li Su virtue, Chen Zongzhang applied for Chinese invention patent " multiband electromagnetic wave absorb composite material and preparation method thereof " (application number 200710303448.0), a kind of graphite composite material with laser, infrared, microwave multiband electromagnetic wave absorptive character is disclosed, the absorbing property at high band 8～18GHz with comparative superiority has maximum reflectivity-15dB when 10GHz.
On October 5th, 2011, golden hypo, Li Dan etc. applied for Chinese invention patent " preparation method of a kind of aluminium-nitrogen co-doped silicon carbide absorbing material " (application number 201110075328.6), a kind of preparation method that aluminium-nitrogen co-doped silicon carbide absorbing material is provided is disclosed, can improve concentration and electroconductibility and the lossy microwave performance of silicon carbide, with short production cycle, equipment and technique are simple, and can realize controllable doped.Silicon carbide is a kind of desirable new type high temperature absorbing material, has the premium propertiess such as density is little, high temperature resistant, thermostability is high, wearability is good, is mainly used in high band (8～18GHz).
On December 24th, 2008, Zhang Yanqing, hero were applied for Chinese invention patent " for ferrite-nickle composite powder and the preparation method of electromagnetic wave absorption " (application number 200810041222.2), disclose and a kind ofly take metal nickel powder as body material, adopted chemical process to obtain ferrite-metallic nickel composite granule at the coated ferrite layer in nickel powder surface.Ferrite wave-absorbing material has excellent absorbing property in low-frequency range (2～8GHz), and weak point is mainly that frequency band is narrow, density is large, Curie temperature is low etc.
6 Chen states beam application March in 2002 Chinese invention patent " dielectricity electromagnetic absorber and manufacture method thereof and application " (application number 00121295.8), the dielectricity electromagnetic-wave absorbent that a kind of electro-conductive fiber and powdered carbon, inorganic micro-hollow ball are composited is disclosed, decay and carry out electromagnetic wave absorption in electronic polarization by medium or interface, hertzian wave is transformed into heat energy., be mainly used in high band (8～18GHz).
Female bright, Ji Song of on April 27th, 2011 etc. has applied for Chinese invention patent " a kind of preparation method of absorbing material " (application number 201010619559.4); announce a kind of method of usining single roller chilling and prepared iron based nano crystal material as mother metal; mother metal is carried out under nitrogen protection to nano-crystallization, high speed cutting and airflow milling and process, obtain micron-sized nanocrystalline material.The absorbing material that adopts the method to prepare has good absorbing property at 2～5GHz, increases, but can't be applied to high temperature range compared with Ferrite Material Curie temperature.
As can be seen here, in the research of absorbing material, more than the absorbing property of traditional absorbing material mainly concentrates on high band 8GHz, at low-frequency range 2～8GHz, there is the technical barrier that excellent absorbing property is microwave absorbing material always.From current progress, absorbing material in 2～8GHz band limits mainly be take metal magnetic powder as main, metal magnetic powder microwave absorbing material is mainly to carry out attenuation by absorption hertzian wave by magnetic hysteresis loss, eddy-current loss, have the advantages that Curie temperature is high, saturation magnetization is high and magnetic permeability is high, be conducive to realize the thin layer of absorbing material.In metal magnetic powder, FeCo base magnetic micro-powder has maximum saturated magnetic moment of atom in Fe base magnetic micro-powder, at Fe, Co atomic ratio, have the highest magnetic permeability while being 1:1, Curie temperature can reach more than 800 ℃, in high temperature low-frequency range (2～8GHz), has excellent absorbing property.
Summary of the invention
The object of the invention is to propose a kind of novel (FeCo) B microwave absorbing material in the band limits of 2～8GHz with excellent absorbing property and preparation method thereof.
For this purpose, the present invention is achieved through the following technical solutions:
A kind of novel (FeCo) B microwave absorbing material, by Fe powder, Co powder and FeB alloy, made, in described material, the massfraction of Fe, Co, each element of B is respectively 47.0～50.0%, 50.0～53.0%, 0.6～0.9%, and each composition sum is 100%.
Further, the preparation method of described novel (FeCo) B microwave absorbing material comprises the steps:
(1) adopting electrical pure iron, electrolytic cobalt and FeB alloy is raw material, carries out vacuum induction melting, and refining temperature is 1500 ℃～1600 ℃, refining time 3min～5min, and casting obtains composition (FeCo) B alloy pig uniformly;
(2) adopt melt press over system that (FeCo) B alloy is carried out to argon shield fast quenching and prepare strip, the linear velocity 30～50m/s of cooling roller, vacuum tightness is 1～2 * 10
-3pa, thickness is less than the strip of 15 μ m;
(3) strip is made to the powder of particle diameter 100 μ m～150 μ m, the treatment time is 0.1～0.2h;
(4) powder is carried out to mechanical mill, ratio of grinding media to material is 40:1, Ball-milling Time 6～12h, and obtaining median size is the powder of 0.5 μ m～2 μ m.
Further, in described step (1), adopting electrical pure iron, electrolytic cobalt and FeB alloy is raw material, carries out melting in high-frequency vacuum induction furnace, and vacuum induction furnace adopts MgO crucible, and melting is front with pure Fe prepurging.
Further; in described step (2), vacuum quick quenching adopts LZK-12A type vacuum quick quenching furnace; described LZK-12A type vacuum quick quenching furnace consists of 12 major partss such as vacuum chamber, feed bin, autofeed, electrode holder, water jacketed copper crucible, crucible dumping machine, molybdenum matter runner and main shaft, runner housing, rewinding bucket, vacuum unit, silicon controlled rectification power source and controllers; adopt melt press over system under argon shield, to carry out fast quenching; the linear velocity of cooling roller is 30～50m/s, and vacuum tightness is 1～2 * 10
-3pa, prepares the strip that thickness is less than 15 μ m.
In described step (3), fast-holding powder process is to make strip make rapidly powder by impact force and frictional force, can reduce the follow-up mechanical mill time.
In described step (4), utilize high energy ball mill to carry out mechanical mill to powder, what ball mill adopted is the QM-4SP3 type planetary ball mill that Nanjing University produces, ball grinder volume is 2 liters, abrading-ball is quenching Stainless Steel Ball, and further, the grinding medium of wet grinding (process control agent of ball milling) is dehydrated alcohol, the volume of dehydrated alcohol is 1/3rd of ball grinder, drum's speed of rotation is 300r/min, and ratio of grinding media to material is 40:1, and Ball-milling Time is 6～12h.
The invention has the advantages that: a kind of novel (FeCo) B microwave absorbing material and preparation method thereof, at low-frequency range 2～8GHz, there is higher magnetic permeability and magnetic loss, there are 800 ℃ of above Curie temperature, this material that 1.8mm is thick has the microwave absorbing property of the highest-11.5dB in 2～8GHz band limits, in high temperature low-frequency range, is with a wide range of applications.
Accompanying drawing explanation
Fig. 1 is that the invention process example 1 is prepared the absorbing property of resulting materials and the relation of frequency;
Fig. 2 is that the invention process example 2 is prepared the absorbing property of resulting materials and the relation of frequency;
Fig. 3 is that the invention process example 3 is prepared the absorbing property of resulting materials and the relation of frequency;
Fig. 4 is that the invention process example 4 is prepared the absorbing property of resulting materials and the relation of frequency;
Fig. 5 is the Electronic Speculum schematic diagram that the invention process example 1 is prepared resulting materials;
Fig. 6 is the Electronic Speculum schematic diagram that the invention process example 2 is prepared resulting materials;
Fig. 7 is the Electronic Speculum schematic diagram that the invention process example 3 is prepared resulting materials;
Fig. 8 is the Electronic Speculum schematic diagram that the invention process example 4 is prepared resulting materials.
Embodiment
Below in conjunction with embodiment, the invention will be further described, but the present invention is not only confined to following examples.
Embodiment 1
Adopting electrical pure iron, electrolytic cobalt and FeB alloy is raw material, and the massfraction of Fe, Co, B is respectively 47.4%, 52.0%, 0.60%.In high-frequency vacuum induction furnace, carry out melting, vacuum induction furnace adopts MgO crucible, and before melting, with pure Fe prepurging, refining temperature is 1500 ℃～1600 ℃, refining time 3min～5min, and casting obtains composition (FeCo) B alloy pig uniformly; Utilize vacuum quick quenching furnace, adopt melt press over system that (FeCo) B alloy is carried out to fast quenching under argon shield and prepare strip, the linear velocity 30m/s of cooling roller, vacuum tightness is 1 * 10
-3pa, prepares the strip that thickness is less than 15 μ m; Utilize quick pressure mill that strip is made to the powder that particle diameter is 100～150 μ m, the treatment time is 0.15h; Utilize high energy ball mill to carry out mechanical mill to powder, the process control agent of ball milling is dehydrated alcohol, and the volume of dehydrated alcohol is ball grinder 1/3rd, and drum's speed of rotation is 300r/min, and ratio of grinding media to material is 5:1, and Ball-milling Time is 6h.
The powder median size preparing is in 2 μ m left and right, and electromicroscopic photograph as shown in Figure 5; After by powder sample, 5:1 heating mixes in mass ratio with paraffin, with mould, being pressed into internal diameter is that the coaxial rings sample that 3.04mm, external diameter 7.0mm, thickness are 2～4mm carries out electromagnetic performance test within the scope of 2～18GHz, utilize the electromagnetic parameter of gained to simulate thickness for the absorbing property of 1.8mm sample and the relation of frequency, as shown in Figure 1; Sample is at the reflectivity R=of 2GHz – 1.6dB, and at the reflectivity R=of 8GHz – 8.4dB, maximum reflectivity appears at 5.8GHz ， Wei – 11.5dB.
Embodiment 2
Adopting electrical pure iron, electrolytic cobalt and FeB alloy is raw material, and the massfraction of Fe, Co, B is respectively 48.3%, 51.0%, 0.70%.In high-frequency vacuum induction furnace, carry out melting, vacuum induction furnace adopts MgO crucible, and before melting, with pure Fe prepurging, refining temperature is 1500 ℃～1600 ℃, refining time 3min～5min, and casting obtains composition (FeCo) B alloy pig uniformly; Utilize vacuum quick quenching furnace, adopt melt press over system that (FeCo) B alloy is carried out to fast quenching under argon shield and prepare strip, the linear velocity 40m/s of cooling roller, vacuum tightness is 1 * 10
-3pa, prepares the strip that thickness is less than 15 μ m; Utilize quick pressure mill that strip is made to the powder that particle diameter is 100～150 μ m, the treatment time is 0.15h; Utilize high energy ball mill to carry out mechanical mill to powder, the process control agent of ball milling is dehydrated alcohol, and the volume of dehydrated alcohol is ball grinder 1/3rd, and drum's speed of rotation is 300r/min, and ratio of grinding media to material is 20:1, and Ball-milling Time is 8h.
The powder median size preparing is in 1.5 μ m left and right, and electromicroscopic photograph as shown in Figure 6; After by powder sample, 5:1 heating mixes in mass ratio with paraffin, with mould, being pressed into internal diameter is that the coaxial rings sample that 3.04mm, external diameter 7.0mm, thickness are 2～4mm carries out electromagnetic performance test within the scope of 2～18GHz, utilize the electromagnetic parameter of gained to simulate thickness for the absorbing property of 1.8mm sample and the relation of frequency, as shown in Figure 2; Sample is at the reflectivity R=of 2GHz – 3.5dB, and at the reflectivity R=of 8GHz – 4.5dB, maximum reflectivity appears at 3.2GHz ， Wei – 7.2dB.
Embodiment 3
Adopting electrical pure iron, electrolytic cobalt and FeB alloy is raw material, and the massfraction of Fe, Co, B is respectively 49.2%, 50.0%, 0.80%.In high-frequency vacuum induction furnace, carry out melting, vacuum induction furnace adopts MgO crucible, and before melting, with pure Fe prepurging, refining temperature is 1500 ℃～1600 ℃, refining time 3min～5min, and casting obtains composition (FeCo) B alloy pig uniformly; Utilize vacuum quick quenching furnace, adopt melt press over system that (FeCo) B alloy is carried out to fast quenching under argon shield and prepare strip, the linear velocity 40m/s of cooling roller, vacuum tightness is 2 * 10
-3pa, prepares the strip that thickness is less than 15 μ m; Utilize quick pressure mill that strip is made to the powder that particle diameter is 100～150 μ m, the treatment time is 0.15h; Utilize high energy ball mill to carry out mechanical mill to powder, the process control agent of ball milling is dehydrated alcohol, and the volume of dehydrated alcohol is ball grinder 1/3rd, and drum's speed of rotation is 300r/min, and ratio of grinding media to material is 30:1, and Ball-milling Time is 10h.
The powder median size preparing is in 1 μ m left and right, and electromicroscopic photograph as shown in Figure 7; After by powder sample, 5:1 heating mixes in mass ratio with paraffin, with mould, being pressed into internal diameter is that the coaxial rings sample that 3.04mm, external diameter 7.0mm, thickness are 2～4mm carries out electromagnetic performance test within the scope of 2～18GHz, utilize the electromagnetic parameter of gained to simulate thickness for the absorbing property of 1.8mm sample and the relation of frequency, as shown in Figure 3; Sample is at the reflectivity R=of 2GHz – 3.4dB, and at the reflectivity R=of 8GHz – 3.8dB, maximum reflectivity appears at 3.1GHz ， Wei – 5.0dB.
Embodiment 4
Adopting electrical pure iron, electrolytic cobalt and FeB alloy is raw material, and the massfraction of Fe, Co, B is respectively 49.0%, 50.1%, 0.90%.In high-frequency vacuum induction furnace, carry out melting, vacuum induction furnace adopts MgO crucible, and before melting, with pure Fe prepurging, refining temperature is 1500 ℃～1600 ℃, refining time 3min～5min, and casting obtains composition (FeCo) B alloy pig uniformly; Utilize vacuum quick quenching furnace, adopt melt press over system that (FeCo) B alloy is carried out to fast quenching under argon shield and prepare strip, the linear velocity 50m/s of cooling roller, vacuum tightness is 2 * 10
-3pa, prepares the strip that thickness is less than 15 μ m; Utilize quick pressure mill that strip is made to the powder that particle diameter is 100～150 μ m, the treatment time is 0.15h; Utilize high energy ball mill to carry out mechanical mill to powder, the process control agent of ball milling is dehydrated alcohol, and the volume of dehydrated alcohol is ball grinder 1/3rd, and drum's speed of rotation is 300r/min, and ratio of grinding media to material is 40:1, and Ball-milling Time is 12h.
The powder median size preparing is in 0.5 μ m left and right, and electromicroscopic photograph as shown in Figure 8; After by powder sample, 5:1 heating mixes in mass ratio with paraffin, with mould, being pressed into internal diameter is that the coaxial rings sample that 3.04mm, external diameter 7.0mm, thickness are 2～4mm carries out electromagnetic performance test within the scope of 2～18GHz, it is the absorbing property of 1.8mm sample and the relation of frequency that the electromagnetic parameter of gained is simulated to thickness, as shown in Figure 4; Sample is at the reflectivity R=of 2GHz – 3.5dB, and at the reflectivity R=of 8GHz – 3.1dB, maximum reflectivity appears at 2.6GHz ， Wei – 3.9dB.
Claims (2)
1. (FeCo) B microwave absorbing material, it is characterized in that, described material is made by Fe powder, Co powder and FeB alloy, powder for median size 0.5 μ m ~ 2 μ m, in described material, the massfraction of Fe, Co, each element of B is respectively 47.0 ~ 50.0%, 50.0 ~ 53.0%, 0.6 ~ 0.9%, and each composition sum is 100%.
2. (FeCo) according to claim 1 B microwave absorbing material, is characterized in that, the preparation method of material comprises the steps:
(1) adopting electrical pure iron, electrolytic cobalt and FeB alloy is raw material, carries out vacuum induction melting, and refining temperature is 1500 ℃ ~ 1600 ℃, refining time 3min ~ 5min, and casting obtains composition (FeCo) B alloy pig uniformly;
(2) adopt melt press over system that (FeCo) B alloy is carried out to argon shield fast quenching and prepare strip, the linear velocity 30 ~ 50m/s of cooling roller, vacuum tightness is 1 ~ 2 * 10
-3pa, thickness is less than the strip of 15 μ m;
(3) strip is made to the powder of particle diameter 100 μ m ~ 150 μ m, the treatment time is 0.1 ~ 0.2h;
(4) powder is carried out to mechanical mill, ratio of grinding media to material is 5:1 ~ 40:1, Ball-milling Time 6 ~ 12h, and obtaining median size is the powder of 0.5 μ m ~ 2 μ m.
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| CN103551568B (en) * | 2013-11-13 | 2015-09-09 | 北京科技大学 | A kind of preparation method of scale-like nanocrystalline high temperature microwave absorbent |
| CN105845435B (en) * | 2016-05-23 | 2018-05-18 | 电子科技大学 | A kind of wide-band and wave-absorbing magnetic film and preparation method thereof |
| CN113621893B (en) * | 2020-05-07 | 2022-03-18 | 南京大学 | High-temperature-resistant sheet iron-cobalt-germanium wave-absorbing material and preparation method and application thereof |
| CN111785469A (en) * | 2020-07-10 | 2020-10-16 | 瑞声科技（南京）有限公司 | Soft magnetic alloy powder and preparation method thereof |
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| JPH06122990A (en) * | 1992-10-12 | 1994-05-06 | Sumitomo Metal Ind Ltd | Co-fe-b alloy electroplating film and its production |
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