CN106495700B - A kind of method that presoma conversion method prepares SiCN (Fe) precursor ceramic of rare earth doped oxide - Google Patents

A kind of method that presoma conversion method prepares SiCN (Fe) precursor ceramic of rare earth doped oxide Download PDF

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CN106495700B
CN106495700B CN201610962212.7A CN201610962212A CN106495700B CN 106495700 B CN106495700 B CN 106495700B CN 201610962212 A CN201610962212 A CN 201610962212A CN 106495700 B CN106495700 B CN 106495700B
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rare earth
sicn
powder
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CN106495700A (en
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龚红宇
刘玉
张玉军
冯玉润
郭学
林骁
周立伟
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Shandong University
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Abstract

The present invention relates to a kind of methods that presoma conversion method synthesizes the silicon carbonitride ceramic containing ferromagnetism of rare earth doped oxide.It is as follows that the method comprising the steps of: (1) polysilazane, α-methacrylic acid and cumyl peroxide is mixed, obtains mixed solution；(2) mixed solution is solidified；(3) solidify obtained material it is pre-milled, crush ball milling, sieving, obtain powder granule；(4) alpha-iron oxide nano-powder and RE oxide powder are added into powder granule, obtains mixed material；(5) by mixed material compression moulding, isostatic cool pressing, pressure maintaining obtains green compact；(6) by gained green compact 1000 DEG C -1400 DEG C temperature sintering to get.This method simple process, production cost be low, short preparation period, and obtained product electromagnetic wave attenuation coefficient is high, and microwave absorbing property is good.

Description

A kind of presoma conversion method prepares SiCN (Fe) the presoma pottery of rare earth doped oxide The method of porcelain
Technical field
The present invention relates to the preparation methods of the SiCN of rare earth doped oxide (Fe) precursor ceramic, and in particular to Yi Zhongqian The method that body conversion method synthesizes the silicon carbonitride ceramic containing ferromagnetism of rare earth doped oxide is driven, inorganic non-metallic material neck is belonged to Domain.
Background technique
With the development of science and technology, electromagenetic wave radiation has become a big harm, not only periodic traffic and electronic system are made At damage, human health can be also damaged.And the progress of Detection Techniques, so that realizing that target is stealthy, it is military to improve in modern war The existence of device change system and penetration ability have profound significance, therefore electromangnetic spectrum just seems particularly significant.And it is electric The incident electromagnetic wave of electro-magnetic wave absorption material absorbable, decaying, and convert electromagnetic energy into thermal energy and dissipate, or make electromagnetic wave because Interfere and cancellation, therefore electromagnetic wave absorbent material becomes research hotspot in recent years.
More typical traditional absorbing material, such as ferrite, graphite, have that absorb that strong, at low cost, frequency band is wider etc. excellent Point, but at the same time, it may have the disadvantages of high-temperature behavior is poor, density is big, therefore it is limited in the further development in the field. And the ceramic materials such as SiCN, mullite, absorbing property are more preferable, and the energy of radar wave can effectively be lost.
Precursor ceramic (Polymer-Derived Ceramics (PDCs)) is that organic polymer presoma is directly warm Ceramic material obtained from solution, can by change presoma chemical composition and technique come change precursor ceramic structure and Composition.It, can be directly by liquid organic precursor in a mold through photocuring or heat using presoma pyrolysismethod ceramics preparation process After curing molding, pyrolysis sintering obtains the ceramics of specific form structure, and product has the microstructure of stable homogeneous.
It is a kind of dielectric loss type absorbing material using SiCN precursor ceramic prepared by this presoma conversion method, because of it The excellent mechanical performance such as high intensity, high-modulus, high rigidity, low-density, heat resistance, chemical stabilization, oxidation resistance etc. and At home and abroad receive extensive concern.And other elements M (B, Al, Fe, Co, Mo are further introduced into SiCN precursor ceramic Deng), SiCN (M) precursor ceramic is made, ceramic electromagnetic performance can be improved.And why absorbing property greatly promotes, be because Require greatly more to meet the two of absorbing material: impedance matching (wave enters wave-absorber without reflecting) and loss (inhale wave material Material has enough lossies to the wave of injection).The source Fe preparation SiCN (Fe) precursor ceramic is introduced at present has obtained extensive research.
Chinese patent literature CN 105000889A discloses a kind of side of presoma conversion method preparation iron content silicon carbonitride ceramic Method.It is as follows that the method comprising the steps of: (1) being uniformly mixed polysilazane, α-methacrylic acid, cumyl peroxide, obtain mixed Close solution；(2) mixed solution is solidified；(3) solidify resulting crushing material ball milling；(4) by the powder and nano oxygen after ball milling Change iron to be uniformly mixed；(5) by gained powder pre-molding, green compact are obtained；(6) by green compact obtained by step (5) at 1000 DEG C -1400 DEG C Temperature be pyrolyzed/be sintered, keep the temperature to obtain the final product.The method preparation process is simple, and resulting materials high-temperature behavior is excellent, has certain Absorbing property, but absorbing property is not good enough.
Chinese patent literature CN 104944960A discloses a kind of presoma conversion method preparation nitrogen of silicon-carbon containing ferric acetyl acetonade The method of ceramics.The following steps are included: polysilazane, α-methacrylic acid, cumyl peroxide are uniformly mixed by (1), obtain Mixed solution；(2) mixed solution is solidified；(3) resulting crushing material ball milling will be solidified；(4) by powder and ferric acetyl acetonade It is uniformly mixed；(5) by uniformly mixed powder pre-molding, green compact are obtained；(6) green compact are carried out in 1000 DEG C -1400 DEG C of temperature Pyrolysis/sintering, heat preservation to get.The material at high temperature performance that the invention is prepared is good, has certain microwave absorbing property, but Assimilation effect is not good enough.
Rare earth element is the element of a kind of not pairs of 4f electronics for having and being shielded by outermost electron, has magnetic moment, and not The transition elements such as Fe, Co, Ni are same as, they are affected by the surrounding environment smaller, and the interaction with ambient enviroment is to hand over indirectly The effect of changing, to there is the Net magnetic moment not being cancelled.So rare earth has good paramagnetic susceptibility, saturation magnetization, magnetocrystalline Anisotropy and magnetostriction.Therefore, the electronic structure and electromagnetic performance special based on rare earth element, can be with rare earth oxide It as dopant, is introduced into other absorbing materials, to further enhance the absorbing property of material.
Summary of the invention
In view of the deficiencies of the prior art, the present invention provides the SiCN that a kind of presoma conversion method prepares rare earth doped oxide (Fe) method of precursor ceramic.This method simple process, production cost be low, short preparation period, obtained product electromagnetic wave Attenuation coefficient is high, and microwave absorbing property is good.
Technical scheme is as follows:
A kind of method that presoma conversion method prepares SiCN (Fe) precursor ceramic of rare earth doped oxide, including step It is as follows:
(1) mixing: under an inert atmosphere, polysilazane, α-methacrylic acid and cumyl peroxide are mixed 1-2h obtains mixed solution；
The polysilazane: the mass ratio of cumyl peroxide is 96-98:2-4；The addition of the α-methacrylic acid Amount is the 10%-20% of polysilazane and cumyl peroxide gross mass；
(2) crosslinking curing: by mixed solution obtained by step (1) under 400 DEG C -600 DEG C, vacuum condition, solidify 2-4h；
(3) crush ball milling: the material that step (2) crosslinking curing is obtained is pre-milled, crushes ball milling, sieving, obtains powder Body particle；
(4) mixing: being added alpha-iron oxide nano-powder in the powder granule obtained to step (3), is uniformly mixed, obtains mixed powder Body；Then RE oxide powder is added, is uniformly mixed, obtains mixed material；
(5) granulating and forming: by mixed material compression moulding obtained by step (4), isostatic cool pressing, pressure maintaining obtains green compact；
(6) pyrolysis/sintering: under inert gas protection by green compact obtained by step (5), in 1000 DEG C -1400 DEG C of temperature 2-4h is sintered to get SiCN (Fe) precursor ceramic of rare earth doped oxide.
, according to the invention it is preferred to, polysilazane is HTT1800 in the step (1).HTT1800 can market buy, It can be obtained by prior art preparation；The α-methacrylic acid is referred to as MA, and the cumyl peroxide is referred to as DCP。
, according to the invention it is preferred to, polysilazane in the step (1): the mass ratio of cumyl peroxide is 98:2.
, according to the invention it is preferred to, inert atmosphere is nitrogen, argon gas or helium atmosphere in the step (1).
, according to the invention it is preferred to, heating rate is 2-5 DEG C/min in the step (2)；500-600 DEG C of solidification temperature, Curing time 3-4h；Preferably, heating rate is 3-4 DEG C/min.Lower heating rate and higher curing time are to guarantee The full cross-linked solidification of polysilazane promotes the progress of reaction.
, according to the invention it is preferred to, the quality of nano iron oxide and step (3) gained powder granule in the step (4) Than for 40-60:40-60.
, according to the invention it is preferred to, the additional amount of step (4) middle rare earth is the 2%- of mixed powder quality 40%；Preferably, the additional amount of rare earth oxide is the 10%-30% of mixed powder quality；It is further preferred that rare-earth oxidation The additional amount of object is the 5% of mixed powder quality.
, according to the invention it is preferred to, step (4) middle rare earth is Dy2O3、Eu2O3、Sm2O3、Y2O3Or Gd2O3。
It is further preferred that the rare earth oxide is Eu2O3。
, according to the invention it is preferred to, the compression moulding under the pressure of 10MPa in the step (5)；Preferably, the step Suddenly isostatic cool pressing is carried out at 180MPa in (5), pressure maintaining 300s.
, according to the invention it is preferred to, inert gas is nitrogen, argon gas or helium in the step (6).
, according to the invention it is preferred to, heating rate is 3-5 DEG C/min in the step (6).
The principle of the present invention:
SiCN precursor ceramic material has excellent dielectric properties, introduces source of iron in SiCN precursor ceramic, can make Its dielectric loss increases, and increases magnetic loss, realizes loss mechanisms diversification.On this basis, rare earth element is utilized A certain amount of rare earth oxide is mixed in SiCN (Fe) absorbing material matrix, can be adjusted by special electronic structure and electromagnetic performance The electromagnetic parameter of section, optimization absorbing material, achievees the purpose that further increase Absorbing Materials.
Due to compared to other sources of iron, Fe2O3Addition to the dielectric loss of material and being affected for magnetic loss.Therefore The present invention is with dopen Nano Fe2O3SiCN (Fe) precursor ceramic as matrix.
Rare earth element is different from the transition elements such as Fe, Co, Ni, has good paramagnetic susceptibility, saturation magnetization, magnetic Anisotropic crystalline and magnetostriction.A certain amount of rare earth oxide is mixed in SiCN (Fe) precursor ceramic, material magnetic can be changed The imaginary part of media property and dielectric properties, the imaginary part and complex dielectric permittivity that make its complex permeability increases, and promotes magnetic loss and dielectric The increase of loss.The incorporation of rare earth oxide also improves the magnetic anisotropy of absorbing material, on the basis of SiCN (Fe), not only Absorbing property is improved, and more efficiently improves the microwave absorbing property of material.
Beneficial effects of the present invention are as follows:
1, the present invention prepares SiCN (Fe) precursor ceramic of rare earth doped oxide by presoma conversion method, forms good Well, there is some strength, on the basis of nano iron oxide is introduced in SiCN precursor ceramic, be further doped with rare-earth oxidation Object utilizes rare earth oxide special electronic structure and electromagnetic performance, it will be apparent that the microwave absorbing property for improving SiCN ceramics mentions Its high electromagnetic wave attenuation coefficient.
2, the present invention uses presoma conversion method, and preparation temperature is low, and preparation method is simple, and production cost is low, manufacturing cycle Short, resulting materials chemical stability, high-temperature behavior are good.
Detailed description of the invention
Fig. 1 is that the X-ray of SiCN (Fe) precursor ceramic of rare earth doped oxide obtained by the embodiment of the present invention 1 is spread out Penetrate map.
Fig. 2 is that the SEM of SiCN (Fe) precursor ceramic of rare earth doped oxide obtained by the embodiment of the present invention 1 shines Piece.
Fig. 3 is that the frequency-of SiCN (Fe) precursor ceramic of rare earth doped oxide obtained by the embodiment of the present invention 1 is anti- Penetrate rate R change curve.
Fig. 4 is the frequency-electricity of SiCN (Fe) precursor ceramic of rare earth doped oxide obtained by the embodiment of the present invention 1 Magnetic attenuation coefficient a change curve.
Fig. 5 is the frequency-reflection of SiCN (Fe) precursor ceramic of rare earth doped oxide obtained by embodiment 1,2,3 Rate R change curve compares figure.
Fig. 6 is the frequency-reflection of SiCN (Fe) precursor ceramic of rare earth doped oxide obtained by embodiment 4,5,6 Rate R change curve compares figure.
Fig. 7 is the frequency-reflection of SiCN (Fe) precursor ceramic of rare earth doped oxide obtained by embodiment 7,8,9 Rate R change curve compares figure.
Fig. 8 is the frequency-electromagnetism of SiCN (Fe) precursor ceramic of rare earth doped oxide obtained by embodiment 1,2,3 Attenuation coefficient a change curve compares figure.
Fig. 9 is the frequency-electromagnetism of SiCN (Fe) precursor ceramic of rare earth doped oxide obtained by embodiment 4,5,6 Attenuation coefficient a change curve compares figure.
Figure 10 is the frequency-electricity of SiCN (Fe) precursor ceramic of rare earth doped oxide obtained by embodiment 7,8,9 Magnetic attenuation coefficient a change curve compares figure.
Specific embodiment
Below with reference to embodiment, technical scheme is described further, but institute's protection scope of the present invention is not limited to This.
Raw materials used in embodiment is conventional raw material, and device therefor is conventional equipment, commercial products.
Polysilazane used is HTT1800, and commercial products come from Shanghai Hai Yi scientific & trading Co., Ltd..
Embodiment 1
A kind of method that presoma conversion method prepares SiCN (Fe) precursor ceramic of rare earth doped oxide, including step It is as follows:
(1) mixing: in N2Under atmosphere, polysilazane 9.8g, α-methacrylic acid 2g, cumyl peroxide are weighed 0.2g is added in reaction flask, 1h is stirred in constant temperature blender with magnetic force, obtains single transparent mixed solution；
Polysilazane in the mixed solution: the mass ratio of cumyl peroxide is 98:2, the α-methacrylic acid Additional amount be the 20% of polysilazane and cumyl peroxide gross mass；
(2) crosslinking curing: mixed solution obtained by step (1) is heated in vacuum tube furnace and is allowed to crosslinking curing, from room Temperature is warming up to 600 DEG C of solidification 4h, and temperature rate is 3 DEG C/min；
(3) crush ball milling: then the material for taking step (2) crosslinking curing to obtain, in the agate mortar precomminution are being vibrated Ball milling is crushed in ball mill, is sieved with 100 mesh sieve, and powder granule is obtained；
(4) mixing: taking the resulting powder granule 10.5g of step (3), and alpha-iron oxide nano-powder 9.5g is added, and is uniformly mixed, Obtain mixed powder；
The mass ratio of nano iron oxide and step (3) gained powder granule is 47.5:52.5 in the mixed powder；
By 1g Eu2O3Powder is added in above-mentioned resulting mixed powder, is uniformly mixed in the agate mortar, obtains mixture Material；The Eu2O3The quality of powder is the 5% of mixed powder quality；
(5) granulating and forming: mixed material obtained by step (4) is fitted into mold, single shaft is pressed under the pressure of 10MPa Type, then under 180MPa isostatic cool pressing, pressure maintaining 300s obtains green compact；
(6) pyrolysis/sintering: green compact obtained by step (5) are fitted into tube furnace, in N2Under atmosphere protection, at 1000 DEG C Temperature be pyrolyzed 4h, 3 DEG C/min of heating rate to get rare earth doped oxide SiCN (Fe) precursor ceramic.
SiCN (Fe) precursor ceramic for the rare earth doped oxide that the present embodiment is prepared tests X-ray diffractogram Spectrum, SEM photograph, frequency-reflectivity R and frequency-electromagnetic attenuation coefficient a change curve Comparative map, as shown in Figure 1,2,3, 4.
As shown in Figure 1, in obtained product other than containing Fe, also containing the rare earth oxide adulterated.
As shown in Figure 2, the incorporation of rare earth oxide changes less SiCN (Fe) precursor ceramic structure, final product point It is good to dissipate property, no crystal grain adhesion agglomeration.
By Fig. 3,4 it is found that with frequency increase, reflectivity be in decreasing trend, electromagnetic attenuation coefficient be in increase tendency, i.e., Sample electromagnetic wave absorption performance increases with the increase of frequency.Reflectivity reaches minimum -18 at 16.6GHz, and electromagnetic attenuation Coefficient also reaches maximum value 653 at 16.1GHz.It follows that prepared material has excellent absorbing property.
Embodiment 2
A kind of method that presoma conversion method prepares SiCN (Fe) precursor ceramic of rare earth doped oxide, including step It is as follows:
(1) mixing: in N2Under atmosphere, polysilazane 9.8g, α-methacrylic acid 2g, cumyl peroxide are weighed 0.2g is added in reaction flask, 1h is stirred in constant temperature blender with magnetic force, obtains single transparent mixed solution；
Polysilazane in the mixed solution: the mass ratio of cumyl peroxide is 98:2, the α-methacrylic acid Additional amount be the 20% of polysilazane and cumyl peroxide gross mass；
(2) crosslinking curing: mixed solution obtained by step (1) is heated in vacuum tube furnace and is allowed to crosslinking curing, from room Temperature is warming up to 600 DEG C of solidification 4h, and temperature rate is 5 DEG C/min；
(3) crush ball milling: then the material for taking step (2) crosslinking curing to obtain, in the agate mortar precomminution are being vibrated Ball milling is crushed in ball mill, is sieved with 100 mesh sieve, and powder granule is obtained；
(4) mixing: taking the resulting powder granule 10.5g of step (3), and alpha-iron oxide nano-powder 9.5g is added, and is uniformly mixed, Obtain mixed powder；
The mass ratio of nano iron oxide and step (3) gained powder granule is 47.5:52.5 in the mixed powder；
By 1g Dy2O3Powder is added in above-mentioned gained mixed powder, is uniformly mixed in the agate mortar, obtains mixture Material；The Dy2O3The quality of powder is the 5% of mixed powder quality；
(5) granulating and forming: mixed material obtained by step (4) is fitted into mold, single shaft is pressed under the pressure of 10MPa Type, then under 180MPa isostatic cool pressing, pressure maintaining 300s obtains green compact；
(6) pyrolysis/sintering: green compact obtained by step (5) are fitted into tube furnace, in N2Under atmosphere protection, at 1100 DEG C Temperature be pyrolyzed 4h, 5 DEG C/min of heating rate to get rare earth doped oxide SiCN (Fe) precursor ceramic.
Embodiment 3
A kind of method that presoma conversion method prepares SiCN (Fe) precursor ceramic of rare earth doped oxide, including step It is as follows:
(1) mixing: in N2Under atmosphere, polysilazane 9.6g, α-methacrylic acid 2g, cumyl peroxide are weighed 0.4g is added in reaction flask, 1h is stirred in constant temperature blender with magnetic force, obtains single transparent mixed solution；
Polysilazane in the mixed solution: the mass ratio of cumyl peroxide is 96:4, the α-methacrylic acid Additional amount be the 20% of polysilazane and cumyl peroxide gross mass；
(2) crosslinking curing: mixed solution obtained by step (1) is heated in vacuum tube furnace and is allowed to crosslinking curing, from room Temperature is warming up to 400 DEG C of solidification 4h, and temperature rate is 3 DEG C/min；
(3) crush ball milling: then the material for taking step (2) crosslinking curing to obtain, in the agate mortar precomminution are being vibrated Ball milling is crushed in ball mill, is sieved with 100 mesh sieve, and powder granule is obtained；
(4) mixing: taking the resulting powder granule 10.5g of step (3), and alpha-iron oxide nano-powder 9.5g is added, and is uniformly mixed, Obtain mixed powder；
The mass ratio of nano iron oxide and step (3) gained powder granule is 47.5:52.5 in the mixed powder；
By 1g Sm2O3Powder is added in above-mentioned gained mixed powder, is uniformly mixed in the agate mortar, obtains mixture Material；The Sm2O3The quality of powder is the 5% of mixed powder quality；
(5) granulating and forming: mixed material obtained by step (4) is fitted into mold, single shaft is pressed under the pressure of 10MPa Type, then under 180MPa isostatic cool pressing, pressure maintaining 300s obtains green compact；
(6) pyrolysis/sintering: green compact obtained by step (5) are fitted into tube furnace, in N2Under atmosphere protection, at 1300 DEG C Temperature be pyrolyzed 4h, 3 DEG C/min of heating rate to get rare earth doped oxide SiCN (Fe) precursor ceramic.
Embodiment 4
A kind of method that presoma conversion method prepares SiCN (Fe) precursor ceramic of rare earth doped oxide, including step It is as follows:
(1) mixing: in N2Under atmosphere, polysilazane 9.6g, α-methacrylic acid 2g, cumyl peroxide are weighed 0.4g is added in reaction flask, 1h is stirred in constant temperature blender with magnetic force, obtains single transparent mixed solution；
Polysilazane in the mixed solution: it is 96:4, the α-methacrylic acid that cumyl peroxide, which obtains mass ratio, Additional amount be the 20% of polysilazane and cumyl peroxide gross mass；
(2) crosslinking curing: mixed solution obtained by step (1) is heated in vacuum tube furnace and is allowed to crosslinking curing, from room Temperature is warming up to 600 DEG C of solidification 4h, and temperature rate is 5 DEG C/min；
(3) crush ball milling: then the material for taking step (2) crosslinking curing to obtain, in the agate mortar precomminution are being vibrated Ball milling is crushed in ball mill, is sieved with 100 mesh sieve, and powder granule is obtained；
(4) mixing: taking powder granule 10.5g obtained by step (3), and alpha-iron oxide nano-powder 9.5g is added, and is uniformly mixed, obtains To mixed powder；
The mass ratio of nano iron oxide and step (3) gained powder granule is 47.5:52.5 in the mixed powder；
By 1g Y2O3Powder is added in above-mentioned gained mixed powder, is uniformly mixed in the agate mortar, obtains mixed material； The Y2O3The quality of powder is the 5% of mixed powder quality；
(5) granulating and forming: mixed material obtained by step (4) is fitted into mold, single shaft is pressed under the pressure of 10MPa Type, then under 180MPa isostatic cool pressing, pressure maintaining 300s obtains green compact；
(6) pyrolysis/sintering: green compact obtained by step (5) are fitted into tube furnace, in N2Under atmosphere protection, at 1300 DEG C Temperature be pyrolyzed 4h, 5 DEG C/min of heating rate to get rare earth doped oxide SiCN (Fe) precursor ceramic.
Embodiment 5
A kind of method that presoma conversion method prepares SiCN (Fe) precursor ceramic of rare earth doped oxide, including step It is as follows:
(1) mixing: in N2Under atmosphere, polysilazane 9.7g, α-methacrylic acid 2g, cumyl peroxide are weighed 0.3g is added in reaction flask, 1h is stirred in constant temperature blender with magnetic force, obtains single transparent mixed solution；
Polysilazane in the mixed solution: the mass ratio 97:3 of cumyl peroxide, the α-methacrylic acid Additional amount is the 20% of polysilazane and cumyl peroxide gross mass；
(2) crosslinking curing: mixed solution obtained by step (1) is heated in vacuum tube furnace and is allowed to crosslinking curing, from room Temperature is warming up to 400 DEG C of solidification 4h, and temperature rate is 5 DEG C/min；
(3) crush ball milling: then the material for taking step (2) crosslinking curing to obtain, in the agate mortar precomminution are being vibrated Ball milling is crushed in ball mill, is sieved with 100 mesh sieve, and powder granule is obtained；
(4) mixing: taking powder granule 10.5g obtained by step (3), and alpha-iron oxide nano-powder 9.5g is added, and is uniformly mixed, obtains To mixed powder；
The mass ratio of nano iron oxide and step (3) gained powder granule is 47.5:52.5 in the mixed powder；
By 1g Gd2O3Powder is added in above-mentioned gained mixed powder, is uniformly mixed in the agate mortar, obtains mixture Material；The Gd2O3The quality of powder is the 5% of mixed powder quality；
(5) granulating and forming: mixed material obtained by step (4) is fitted into mold, single shaft is pressed under the pressure of 10MPa Type, then under 180MPa isostatic cool pressing, pressure maintaining 300s obtains green compact；
(6) pyrolysis/sintering: green compact obtained by step (5) are fitted into tube furnace, in N2Under atmosphere protection, at 1400 DEG C Temperature be pyrolyzed 4h, 3 DEG C/min of heating rate to get rare earth doped oxide SiCN (Fe) precursor ceramic.
Embodiment 6
A kind of method that presoma conversion method prepares SiCN (Fe) precursor ceramic of rare earth doped oxide, including step It is as follows:
(1) mixing: in N2Under atmosphere, polysilazane 9.8g, α-methacrylic acid 2g, cumyl peroxide are weighed 0.2g is added in reaction flask, 1h is stirred in constant temperature blender with magnetic force, obtains single transparent mixed solution；
Polysilazane in the mixed solution: the mass ratio of cumyl peroxide is 98:2, the α-methacrylic acid Additional amount be the 20% of polysilazane and cumyl peroxide gross mass；
(2) crosslinking curing: mixed solution obtained by step (1) is heated in vacuum tube furnace and is allowed to crosslinking curing, from room Temperature is warming up to 500 DEG C of solidification 2h, and temperature rate is 4 DEG C/min；
(3) crush ball milling: then the material for taking step (2) crosslinking curing to obtain, in the agate mortar precomminution are being vibrated Ball milling is crushed in ball mill, is sieved with 100 mesh sieve, and powder granule is obtained；
(4) mixing: taking the resulting powder granule 10g of step (3), and alpha-iron oxide nano-powder 10g is added, and is uniformly mixed, obtains To mixed powder；
The mass ratio of nano iron oxide and step (3) gained powder granule is 1:1 in the mixed powder；
By 0.4g Eu2O3Powder is added in above-mentioned resulting mixed powder, is uniformly mixed, is mixed in the agate mortar Material；The Eu2O3The quality of powder is the 2% of mixed powder quality；
(5) granulating and forming: mixed material obtained by step (4) is fitted into mold, single shaft is pressed under the pressure of 10MPa Type, then under 180MPa isostatic cool pressing, pressure maintaining 300s obtains green compact；
(6) pyrolysis/sintering: green compact obtained by step (5) are fitted into tube furnace, in N2Under atmosphere protection, at 1000 DEG C Temperature be pyrolyzed 4h, 3 DEG C/min of heating rate to get rare earth doped oxide SiCN (Fe) precursor ceramic.
Embodiment 7
A kind of method that presoma conversion method prepares SiCN (Fe) precursor ceramic of rare earth doped oxide, including step It is as follows:
(1) mixing: in N2Under atmosphere, polysilazane 9.8g, α-methacrylic acid 2g, cumyl peroxide are weighed 0.2g is added in reaction flask, 1h is stirred in constant temperature blender with magnetic force, obtains single transparent mixed solution；
Polysilazane in the mixed solution: the mass ratio of cumyl peroxide is 98:2, the α-methacrylic acid Additional amount be the 20% of polysilazane and cumyl peroxide gross mass；
(2) crosslinking curing: mixed solution obtained by step (1) is heated in vacuum tube furnace and is allowed to crosslinking curing, from room Temperature is warming up to 500 DEG C of solidification 3h, and temperature rate is 4 DEG C/min；
(3) crush ball milling: then the material for taking step (2) crosslinking curing to obtain, in the agate mortar precomminution are being vibrated Ball milling is crushed in ball mill, is sieved with 100 mesh sieve, and powder granule is obtained；
(4) mixing: taking the resulting powder granule 9.5g of step (3), and alpha-iron oxide nano-powder 10.5g is added, and is uniformly mixed, Obtain mixed powder；
The mass ratio of nano iron oxide and step (3) gained powder granule is 52.5:47.5 in the mixed powder；
By 8g Eu2O3Powder is added in above-mentioned resulting mixed powder, is uniformly mixed in the agate mortar, obtains mixture Material；The Eu2O3The quality of powder is the 40% of mixed powder quality；
(5) granulating and forming: mixed material obtained by step (4) is fitted into mold, single shaft is pressed under the pressure of 10MPa Type, then under 180MPa isostatic cool pressing, pressure maintaining 300s obtains green compact；
(6) pyrolysis/sintering: green compact obtained by step (5) are fitted into tube furnace, in N2Under atmosphere protection, at 1000 DEG C Temperature be pyrolyzed 2h, 3 DEG C/min of heating rate to get rare earth doped oxide SiCN (Fe) precursor ceramic.
Embodiment 8
A kind of method that presoma conversion method prepares SiCN (Fe) precursor ceramic of rare earth doped oxide, including step It is as follows:
(1) mixing: in N2Under atmosphere, polysilazane 9.8g, α-methacrylic acid 1g, cumyl peroxide are weighed 0.2g is added in reaction flask, 1h is stirred in constant temperature blender with magnetic force, obtains single transparent mixed solution；
Polysilazane in the mixed solution: the mass ratio of cumyl peroxide is 98:2, the α-methacrylic acid Additional amount be the 10% of polysilazane and cumyl peroxide gross mass；
(2) crosslinking curing: mixed solution obtained by step (1) is heated in vacuum tube furnace and is allowed to crosslinking curing, from room Temperature is warming up to 500 DEG C of solidification 3h, and temperature rate is 4 DEG C/min；
(3) crush ball milling: then the material for taking step (2) crosslinking curing to obtain, in the agate mortar precomminution are being vibrated Ball milling is crushed in ball mill, is sieved with 100 mesh sieve, and powder granule is obtained；
(4) mixing: taking the resulting powder granule 9.5g of step (3), and alpha-iron oxide nano-powder 10.5g is added, and is uniformly mixed, Obtain mixed powder；
The mass ratio of nano iron oxide and step (3) gained powder granule is 52.5:47.5 in the mixed powder；
By 2g Eu2O3Powder is added in above-mentioned resulting mixed powder, is uniformly mixed in the agate mortar, obtains mixture Material；The Eu2O3The quality of powder is the 10% of mixed powder quality；
(5) granulating and forming: mixed material obtained by step (4) is fitted into mold, single shaft is pressed under the pressure of 10MPa Type, then under 180MPa isostatic cool pressing, pressure maintaining 300s obtains green compact；
(6) pyrolysis/sintering: green compact obtained by step (5) are fitted into tube furnace, in N2Under atmosphere protection, at 1000 DEG C Temperature be pyrolyzed 4h, 3 DEG C/min of heating rate to get rare earth doped oxide SiCN (Fe) precursor ceramic.
Embodiment 9
A kind of method that presoma conversion method prepares SiCN (Fe) precursor ceramic of rare earth doped oxide, including step It is as follows:
(1) mixing: in N2Under atmosphere, polysilazane 9.8g, α-methacrylic acid 1.5g, cumyl peroxide are weighed 0.2g is added in reaction flask, 1h is stirred in constant temperature blender with magnetic force, obtains single transparent mixed solution；
Polysilazane in the mixed solution: the mass ratio of cumyl peroxide is 98:2, the α-methacrylic acid Additional amount be the 15% of polysilazane and cumyl peroxide gross mass；
(2) crosslinking curing: mixed solution obtained by step (1) is heated in vacuum tube furnace and is allowed to crosslinking curing, from room Temperature is warming up to 500 DEG C of solidification 3h, and temperature rate is 4 DEG C/min；
(3) crush ball milling: then the material for taking step (2) crosslinking curing to obtain, in the agate mortar precomminution are being vibrated Ball milling is crushed in ball mill, is sieved with 100 mesh sieve, and powder granule is obtained；
(4) mixing: taking the resulting powder granule 9.5g of step (3), and alpha-iron oxide nano-powder 10.5g is added, and is uniformly mixed, Obtain mixed powder；
The mass ratio of nano iron oxide and step (3) gained powder granule is 52.5:47.5 in the mixed powder；
By 6g Eu2O3Powder is added in above-mentioned resulting mixed powder, is uniformly mixed in the agate mortar, obtains mixture Material；The Eu2O3The quality of powder is the 30% of mixed powder quality；
(5) granulating and forming: mixed material obtained by step (4) is fitted into mold, single shaft is pressed under the pressure of 10MPa Type, then under 180MPa isostatic cool pressing, pressure maintaining 300s obtains green compact；
(6) pyrolysis/sintering: green compact obtained by step (5) are fitted into tube furnace, in N2Under atmosphere protection, at 1000 DEG C Temperature be pyrolyzed 3h, 3 DEG C/min of heating rate to get rare earth doped oxide SiCN (Fe) precursor ceramic.
Test example 1
SiCN (Fe) precursor ceramic of the embodiment 1-9 rare earth doped oxide being prepared is subjected to frequency-reflection Rate R change curve Comparative map test, as shown in Fig. 5,6,7.Number 1,2,3,4,5,6,7,8,9 is corresponding implementation respectively in figure The frequency of SiCN (Fe) precursor ceramic of rare earth doped oxide prepared by example 1,2,3,4,5,6,7,8,9-reflectivity R becomes Change curve.
SiCN (Fe) precursor ceramic of the embodiment 1-9 rare earth doped oxide being prepared is subjected to frequency-electromagnetism The test of attenuation coefficient a change curve Comparative map, as shown in Figure 8,9, 10.Number 1,2,3,4,5,6,7,8,9 is respectively in figure The frequency-of SiCN (Fe) precursor ceramic of rare earth doped oxide prepared by corresponding embodiment 1,2,3,4,5,6,7,8,9 Electromagnetic attenuation coefficient a change curve.
Compared by Fig. 5-10 it is found that with frequency increase, reflectivity is in decreasing trend, and electromagnetic attenuation coefficient is in increasing Trend, i.e., sample electromagnetic wave absorption performance increases with the increase of frequency, and mixes Eu2O3Sample variation amplitude it is maximum, 16-17GHz range internal reflection rate has minimum value, and electromagnetic attenuation coefficient reaches maximum value, it follows that doping Eu2O3Sample inhale wave Best performance.
It should be noted that the above list is only a few specific embodiments of the present invention, it is clear that the present invention is not only It is limited to above-described embodiment, there can also be other deformations.Those skilled in the art directly exported from the disclosure of invention or All deformations amplified indirectly, are considered as protection scope of the present invention.

Claims (9)

1. a kind of method that presoma conversion method prepares SiCN (Fe) precursor ceramic of rare earth doped oxide, including step is such as Under:
(1) mixing: under an inert atmosphere, being mixed 1-2h for polysilazane, α-methacrylic acid and cumyl peroxide, Obtain mixed solution；
The polysilazane: the mass ratio of cumyl peroxide is 96-98:2-4；The additional amount of the α-methacrylic acid is The 10%-20% of polysilazane and cumyl peroxide gross mass；
(2) crosslinking curing: by mixed solution obtained by step (1) under 400 DEG C -600 DEG C, vacuum condition, solidify 2-4h；
(3) crush ball milling: the material that step (2) crosslinking curing is obtained is pre-milled, crushes ball milling, sieving, obtains powder Grain；
(4) mixing: being added alpha-iron oxide nano-powder in the powder granule obtained to step (3), is uniformly mixed, obtains mixed powder； Then RE oxide powder is added, is uniformly mixed, obtains mixed material；The rare earth oxide is Eu2O3；Rare earth oxide Additional amount is the 2%-40% of mixed powder quality；
(5) granulating and forming: by mixed material compression moulding obtained by step (4), isostatic cool pressing, pressure maintaining obtains green compact；
(6) it pyrolysis/sintering: under inert gas protection by green compact obtained by step (5), is sintered in 1000 DEG C -1400 DEG C of temperature 2-4h to get rare earth doped oxide SiCN (Fe) precursor ceramic.
2. presoma conversion method according to claim 1 prepares SiCN (Fe) precursor ceramic of rare earth doped oxide Method, which is characterized in that polysilazane is HTT1800 in the step (1).
3. presoma conversion method according to claim 1 prepares SiCN (Fe) precursor ceramic of rare earth doped oxide Method, which is characterized in that polysilazane in the step (1): the mass ratio of cumyl peroxide is 98:2.
4. presoma conversion method according to claim 1 prepares SiCN (Fe) precursor ceramic of rare earth doped oxide Method, which is characterized in that inert atmosphere is nitrogen, argon gas or helium atmosphere in the step (1).
5. presoma conversion method according to claim 1 prepares SiCN (Fe) precursor ceramic of rare earth doped oxide Method, which is characterized in that heating rate is 2-5 DEG C/min in the step (2)；500-600 DEG C of solidification temperature, curing time 3- 4h。
6. presoma conversion method according to claim 1 prepares SiCN (Fe) precursor ceramic of rare earth doped oxide Method, which is characterized in that the mass ratio of nano iron oxide and step (3) gained powder granule is 40-60 in the step (4): 40-60。
7. presoma conversion method according to claim 1 prepares SiCN (Fe) precursor ceramic of rare earth doped oxide Method, which is characterized in that the additional amount of step (4) middle rare earth is the 10%-30% of mixed powder quality.
8. presoma conversion method according to claim 1 prepares SiCN (Fe) precursor ceramic of rare earth doped oxide Method, which is characterized in that the compression moulding under the pressure of 10MPa in the step (5)；Isostatic cool pressing is carried out at 180MPa, Pressure maintaining 300s.
9. presoma conversion method according to claim 1 prepares SiCN (Fe) precursor ceramic of rare earth doped oxide Method, which is characterized in that heating rate is 3-5 DEG C/min in the step (6).
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