CN109369183B - Infrared transparent ceramic material and preparation method thereof - Google Patents

Infrared transparent ceramic material and preparation method thereof Download PDF

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CN109369183B
CN109369183B CN201811523327.1A CN201811523327A CN109369183B CN 109369183 B CN109369183 B CN 109369183B CN 201811523327 A CN201811523327 A CN 201811523327A CN 109369183 B CN109369183 B CN 109369183B
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transparent ceramic
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CN109369183A (en
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李晓东
付仲超
张牧
孙旭东
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Northeastern University China
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Abstract

The invention relates to an infrared transparent ceramic material and a preparation method thereof, wherein the infrared transparent ceramic material has a general formula of Y2O3‑MgO‑Gd2O3By the inclusion of Y2O3Nano-powder of (2), nano-powder of MgO and Gd2O3The nano composite powder is formed by firing the nano composite powder. Y is2O3The volume ratio of the nano-powder of (A) to the nano-powder of MgO is 1:1, Gd2O3The nano powder accounts for 0.01 to 18 percent of the total molar weight of the nano composite powder. The infrared transparent ceramic material of the invention is prepared from Gd2O3Has extremely high density and mechanical strength, and is caused by Gd in the sintering process2O3The addition of the composite material can inhibit the diffusion speed of crystal boundary, reduce the growth speed of crystal grains, reduce the size of the crystal grains of the ceramic material and achieve the aim of fine grain strengthening, and the transmittance of the transparent ceramic material is not affected and the mechanical property is further improved so as to meet the higher performance requirement of the material used as an infrared window.

Description

Infrared transparent ceramic material and preparation method thereof
Technical Field
The invention belongs to the technical field of transparent ceramic materials, and particularly relates to an infrared transparent ceramic material and a preparation method thereof.
Background
Aiming at the development trend of future high-Mach-number missiles and the technical challenges faced by infrared window materials, several common infrared window materials at present are contrastively analyzed. At present, a medium wave infrared detector with the size of 3-5 mu m is widely applied to a plurality of fields such as infrared countermeasure, remote sensing, infrared guidance and detection, high-energy laser weapons, thermal imagers, night vision devices, flame gas detectors, environment monitoring, space communication and the like due to high spatial and temperature resolution. Y is2O3The emissivity has the minimum change along with the wavelength, and has the lowest high-temperature infrared radiation coefficient at the same temperature, thereby being beneficial to reducing the signal-to-noise ratio of the infrared detector and improving the detection resolution. In addition, Y is low phonon energy2O3Has a higher optical quality than other optical materials (sapphire, etc.),AlON, spinel, etc.) has a large cutoff wavelength (about 9.5 μm), and has the advantages of low scattering rate, excellent high-temperature mechanical properties, etc., thus being a promising infrared window material.
Reducing grain size is an effective way to improve mechanical properties without affecting the transmission of polycrystalline ceramics. Y is2O3The mutual solid solubility of the two phases of MgO and MgO is extremely low, and the growth of crystal grains in the sintering process can be effectively inhibited through the pinning effect. Y is2O3the-MgO nano complex phase ceramic has excellent medium wave infrared transmission performance, extremely low high temperature radiation coefficient, excellent high temperature mechanical property, moderate thermal property and thermal shock resistance second to sapphire, so that the-MgO nano complex phase ceramic is expected to become an optimal candidate material for a future high-Mach-number missile infrared window/fairing.
However, due to the increasing requirement of attack rate, the service environment of the infrared window/fairing is increasingly severe, the aerodynamic force and aerodynamic heat generated by friction between the front end of the missile and the atmosphere are also increased sharply during the ultrahigh-speed flight of the missile, the infrared window/fairing is in such a complex thermodynamic mixing action state, and the further improvement and stability of the optical performance and mechanical performance of the infrared window/fairing become the main challenges of the current infrared transparent ceramics. Since optoelectronic systems typically operate under very harsh conditions, there are high performance requirements for infrared window materials, including: 1) optical properties: the optical film has higher transmissivity, low thermal radiation and birefringence and high optical quality in an operating waveband; 2) mechanical properties: the mechanical property is good, and the impact of gravel and rainwater in high-speed flight can be withstood; 3) thermal properties: the thermal conductivity is high, the thermal expansion coefficient is small, and the thermal shock resistance is good; 4) chemical properties: the paint can resist acid and alkali corrosion and rain erosion; 5) electrical properties: low dielectric loss and anti-electromagnetic interference; 6) the material is suitable for processing and coating, and the cost is lower.
Therefore, an infrared transparent ceramic material with further improved mechanical properties while ensuring high transmittance is needed.
Disclosure of Invention
Technical problem to be solved
In order to solve the above problems of the prior art, the present invention provides an infrared transparent ceramic which further improves mechanical properties while ensuring high transmittance, and a method for preparing the same.
(II) technical scheme
In order to achieve the purpose, the invention adopts the main technical scheme that:
the invention provides an infrared transparent ceramic material, which has a general formula: y is2O3-MgO-Gd2O3(ii) a The infrared transparent ceramic material is prepared by adopting a material containing Y2O3Nano-powder of (2), nano-powder of MgO and Gd2O3The nano composite powder body composed of the nano powder is fired; wherein, in the nano-composite powder, Y2O3The volume ratio of the nano-powder of (A) to the nano-powder of MgO is 1:1, Gd2O3The nano powder accounts for 0.01 to 18 percent of the total molar weight of the nano composite powder.
According to a preferred embodiment of the present invention, said Gd2O3The percentage of the nano powder in the total molar amount of the nano composite powder is 5-15%. Preferably, the transmittance of the transparent ceramic material is better between 5 and 10 percent, the hardness of the transparent ceramic material is better between 10 and 15 percent, the requirements of the transmittance and the hardness are comprehensively considered, and the transmittance is more preferably 10 percent.
The invention also provides a preparation method of the infrared transparent ceramic material, which comprises the following steps: s1, preparing the nano-composite powder by adopting a raw material containing Y, a raw material containing Mg and a raw material containing Gd; wherein the raw material containing Y is oxide, salt or crystalline hydrate of salt of Y, the raw material containing Mg is oxide, salt or crystalline hydrate of Mg, and the raw material containing Gd is oxide, salt or crystalline hydrate of salt of Gd; s2, carrying out compression molding treatment on the nano composite powder obtained in the step S1 to obtain a molded biscuit; s3, sintering the molded biscuit to obtain a nano composite sintered body; s4, annealing the nano composite sintered body to obtain the infrared transparent ceramic material;
in the step S3, the sintering treatment adopts a vacuum sintering process, the sintering temperature is 1500-1850 ℃, and the heat preservation time is 0.1-15 h; or
In step S3, the sintering treatment adopts a hot-pressing sintering process, the sintering temperature is 1200-1400 ℃, and the heat preservation time is 0.5-5 h; or
In step S3, the sintering treatment adopts a spark plasma sintering process, the sintering temperature is 1100-1400 ℃, and the heat preservation time is 0.2-1 h; or
In step S3, the sintering process adopts a vacuum hot-pressing sintering process, the sintering temperature is 1300-1800 ℃, and the heat preservation time is 0.5-5 h.
According to a preferred embodiment of the present invention, in step S4, the annealing atmosphere of the annealing treatment includes air or oxygen, the annealing temperature is 1100 to 1500 ℃, and the heat preservation time is 4 to 48 hours.
According to a preferred embodiment of the invention, after the nano composite sintered body is obtained in step S3, sintering is carried out through a hot isostatic pressing sintering process, the sintering temperature is 1500-1850 ℃, the heat preservation time is 2-10 hours, and then the step S4 is carried out; and/or
In step S4, the annealing process includes two times, the nano composite sintered body is subjected to the first annealing process, then sintered by the hot isostatic pressing sintering process at the sintering temperature of 1500-1850 ℃ for 2-10 hours, and then subjected to the second annealing process to obtain the infrared transparent ceramic material.
According to an optional embodiment of the present invention, in step S1, the synthesizing of the nano composite powder by a solid phase method specifically includes the following steps: a1, weighing the raw materials according to the dosage range of Y, Mg and Gd elements defined in claim 1, and mixing the raw materials by wet ball milling to obtain a mixed material; a2, drying, grinding, sieving and granulating the mixed material to obtain a powder mixture; a3, calcining the powder mixture at the temperature of 400-1350 ℃ for 2-6 h to obtain the nano composite powder.
According to an optional embodiment of the present invention, in step S1, a mixed clarified solution of metal ions is obtained from a Y salt, a Mg salt, and a Gd salt, and then a precursor powder containing precipitates of these metal elements is prepared from the mixed clarified solution of metal ions, and the precursor powder is calcined to obtain the nanocomposite powder.
According to an optional embodiment of the invention, the precipitate precursor is prepared by a coprecipitation method, a homogeneous precipitation method or a coprecipitation-hydrothermal method, wherein the calcination temperature is 400-1350 ℃, and the calcination time is 2-6 h.
According to an optional embodiment of the invention, in step S1, a sol-gel method is adopted to synthesize the nano composite powder, and the method specifically comprises the following steps of e1, preparing yttrium nitrate solution, gadolinium nitrate solution, magnesium nitrate solution and citric acid solution with the concentration of 0.5-1 mol/L, e2, mixing yttrium nitrate solution and magnesium nitrate solution according to the dosage range of Y, Mg and Gd elements defined in claim 1, then adding gadolinium nitrate solution, adding citric acid solution with the molar ratio of metal ions in the solution and citric acid being 1:1, finally adding catalyst ethylene glycol, uniformly mixing the whole mixed solution at 60-90 ℃ to obtain colorless transparent gel, e3, placing the colorless transparent gel at 180-280 ℃ and blowing air for physical foaming to obtain dry gel, e4, calcining the dry gel at the calcining temperature of 450-700 ℃ to obtain white oxide mixed nano powder, and e5, performing ball milling treatment on the white oxide mixed nano powder, drying and sieving to obtain the nano composite powder.
According to an optional embodiment of the present invention, in step S1, the synthesis of the nano composite powder by a combustion method specifically includes the following steps: f1, weighing the raw materials according to the dosage range of the Y, Mg and Gd elements defined in the claim 1, and dissolving all the raw materials in nitric acid solution to obtain mixed clarified solution of metal ions; f2, mixing a combustion agent with the mixed clear solution, and heating to above 240 ℃ for combustion reaction; f3, after the combustion reaction is finished, cooling the reaction product to obtain the nano composite powder.
(III) advantageous effects
The invention has the beneficial effects that:
the invention firstly prepares Gd2O3And Y2O3-MgO for recombination and Gd control2O3The doping amount of the Gd is 0.01-18 mol%, and Gd is sintered at high temperature2O3Is dissolved in Y2O3In the matrix. Due to Gd2O3The material has extremely high density and mechanical strength; at the same time due to Gd2O3The existence of the crystal grain boundary can inhibit the diffusion speed of the crystal grain boundary in the sintering process and reduce the growth speed of crystal grains, thereby further reducing the crystal grain size of the ceramic material and achieving the purpose of fine grain strengthening, and the transmittance of the transparent ceramic material is not affected. The invention can further improve the mechanical property of the transparent ceramic material while the transparent ceramic material obtains high transmittance, so as to meet the higher performance requirement of the transparent ceramic material as an infrared window material.
The invention relates to a process for preparing an infrared transparent ceramic material, under the parameter conditions of each sintering process and Gd2O3Can provide enough sintering power. Due to Gd during sintering2O3The addition of the crystal grain size can inhibit the diffusion speed of a crystal boundary, reduce the growth speed of crystal grains, is more beneficial to densification, simultaneously reduces the crystal grain size, has no influence on the transmittance of the transparent ceramic material, has the crystal grain size of 60-600 nm, achieves more than 99.2 percent of theoretical sintering density, meets the optical properties of infrared transmission, low signal-to-noise ratio and the like, simultaneously considers the mechanical and mechanical properties of the transparent ceramic material, has the highest product hardness of 11.15GPa, and obtains the transparent ceramic material with the properties of high density, high transmittance and high hardness. The invention is successfully beneficial to the upgrade of domestic infrared window materials, and makes a solid step for meeting the requirements of future ultra-high Mach number missiles on the infrared window/fairing.
Drawings
FIG. 1 is a transmission image of a nanocomposite powder obtained in example 22 below;
FIG. 2 is a graph of transmittance of an infrared transparent ceramic material prepared in example 31 below;
FIG. 3 is a graph of transmittance of an infrared transparent ceramic material prepared in example 32 below;
FIG. 4 is a photograph of a back-scattered infrared transparent ceramic material prepared as in example 34 below;
FIG. 5 is a drawing showing an object of an infrared transparent ceramic sheet obtained by grinding and polishing the infrared transparent ceramic material obtained in example 35;
fig. 6 is a hardness chart of an infrared transparent ceramic sheet obtained after the infrared transparent ceramic material obtained in example 35 below was ground and polished.
Detailed Description
For the purpose of better explaining the present invention and to facilitate understanding, the present invention will be described in detail by way of specific embodiments with reference to the accompanying drawings.
The invention provides an infrared transparent ceramic material with a general formula of Y2O3-MgO-Gd2O3The infrared transparent ceramic material is prepared from Y-containing material2O3Nano-powder of (2), nano-powder of MgO and Gd2O3The nano composite powder is formed by firing the nano composite powder.
Wherein, in the nano-composite powder, Y2O3The volume ratio of the nano-powder of (A) to the nano-powder of MgO is 1:1, Gd2O3The nano powder accounts for 0.01 to 18 percent of the total molar weight of the nano composite powder.
Specifically, in the compounding process of the entire material, Gd2O3Gd in (b) will replace Y2O3Y in (1), if Gd2O3The doping amount of (b) is more than 18 mol%, Gd2O3The crystal absorption phenomenon may occur to exceed Gd2O3Solid solubility of (B), resulting in Gd2O3Cannot interact with Y2O3And MgO in solid solution to cause Gd2O3Can exist in a single crystal form and influence the mechanical property of the whole composite material. Thus, Gd2O3The doping amount of (B) is preferably controlled to 0.01 to 18 mol%. To control Y2O3The nano-powder of (2) and the nano-powder of MgO are mixed in a volume ratio of 1:1 so as not to generate a third phase.
It should be noted that, because of the different processes for preparing the nanocomposite powder, the magnesium oxide and yttrium oxide may not be separated in practice. However, in the present invention, the defined volume ratio of 1:1 is the volume ratio of the nano-powder in the case where the division is set to be possible.
More preferably Gd2O3The nano powder accounts for 5-10% of the total molar weight of the nano composite powder, and the composite material obtained in the range can keep higher transmittance and has higher mechanical property. Preferably, the transmittance of the transparent ceramic material is better between 5 and 10 percent, the hardness of the transparent ceramic material is better between 10 and 15 percent, the requirements of the transmittance and the hardness are comprehensively considered, and the transmittance is more preferably 10 percent.
Thus, Gd is firstly converted into Gd2O3And Y2O3-MgO for recombination and Gd control2O3The doping amount of the Gd is 0.01-18 mol%, and Gd is sintered at high temperature2O3Is dissolved in Y2O3In the matrix. Due to Gd2O3Has extremely high density and mechanical strength and is simultaneously provided with Gd2O3Due to Gd during sintering2O3The addition of the composite material can inhibit the diffusion speed of a crystal boundary and reduce the growth speed of crystal grains, thereby further reducing the crystal grain size of the ceramic material and achieving the purpose of fine grain strengthening, and the transmittance of the transparent ceramic material is not affected.
In another aspect, the present invention provides a method for preparing the above infrared transparent ceramic material, comprising the following steps:
s1 preparation of Y from Y-containing raw material, Mg-containing raw material and Gd-containing raw material2O3-MgO-Gd2O3The nano composite powder of (1).
Wherein the raw material containing Y is oxide, salt or crystalline hydrate of salt of Y, the raw material containing Mg is oxide, salt or crystalline hydrate of Mg, and the raw material containing Gd is oxide, salt or crystalline hydrate of salt of Gd.
In practical application, all raw materials are analytical pure reagents, and the raw material containing Y is generally Y2O3And Y (NO)3)3·6H2At least one of O, the purity of which is more than or equal to 99.99%; the Mg-containing feedstock is typically MgO and Mg (NO)3)2·6H2At least one of O, the purity of which is more than or equal to 99.99%; the Gd-containing material is generally Gd2O3And Gd (NO)3)3·6H2At least one of O, the purity of which is more than or equal to 99.99 percent.
S2, carrying out compression molding treatment on the nano composite powder obtained in the step S1 to obtain a molded biscuit.
Specifically, in step S2, the press forming process includes performing dry press forming by axial unidirectional pressurization, and then performing cold isostatic pressing on the green body after the dry press forming.
In general, the nano composite powder is first loaded into a steel die (for example, a steel die with a diameter of 25mm may be loaded, and the diameter of the steel film is selected according to actual needs), and then is subjected to compression molding. The forming pressure of dry pressing forming is 50-100 MPa, the pressure maintaining time is 1-5 min, the forming pressure of cold isostatic pressing forming is 180-400 MPa, and the pressure maintaining time is 1-5 min.
And S3, sintering the molded biscuit to obtain the nano composite sintered body.
In step S3, the sintering process may be implemented by a vacuum sintering process, a hot-pressing sintering process, a Spark Plasma (SPS) sintering process, or a vacuum hot-pressing sintering process.
Specifically, when the vacuum sintering process is adopted, the formed biscuit is placed in a vacuum sintering furnace for vacuum sintering, the sintering temperature is 1500-1850 ℃, the heat preservation time is 0.1-15 h, and the vacuum degree is 10-3～10-4Pa。
When the hot-pressing sintering process is adopted, the formed biscuit is generally placed in a graphite mold, the graphite mold is charged, protective argon is introduced through an alumina tube, the applied pressure is 10-70 MPa, the sintering temperature is 1200-1400 ℃, and the heat preservation time is 0.5-5 h.
When the spark plasma sintering process is adopted, the formed biscuit is placed in an SPS sintering furnace for sintering, the applied pressure is 10-70 Mpa, the sintering temperature is 1100-1400 ℃, and the heat preservation time is 0.2-1 h.
When the vacuum hot-pressing sintering process is adopted, the formed biscuit is placed in a vacuum hot-pressing furnace, the applied pressure is 10-70 Mpa, the sintering temperature is 1300-1800 ℃, the heat preservation time is 0.5-5 h, and the vacuum degree is about 10-3Pa。
For the four sintering processes, when the sintering temperature is less than the minimum value of each range, incomplete sintering may be caused, and the mechanical properties of the sintered ceramic are affected; when the sintering temperature is higher than the maximum value of each range, the product may further react with other substances, which affects the mechanical properties and wastes resources. Therefore, the sintering temperature for each sintering process is preferably controlled within the above range to obtain the best mechanical properties of the material.
Optionally, after the primary sintering process of step S3, the obtained product is placed in a hot isostatic pressing sintering furnace to be sintered for a second time through the hot isostatic pressing sintering process, the applied pressure is 150 to 200MPa, the sintering temperature is 1500 to 1850 ℃, the heat preservation time is 2 to 10 hours, and then the obtained product is annealed in step S4. And the sintering is carried out twice, so that air holes can be further eliminated, the densification of the ceramic material is facilitated, and the optical light transmittance and the mechanical property are improved.
And S4, placing the nano composite sintered body in a muffle furnace, heating to an annealing temperature at a rate of 20 ℃/min, and then annealing to obtain the infrared transparent ceramic material.
Specifically, in step S4, the annealing atmosphere of the annealing treatment includes air or oxygen, the annealing temperature is 1100 to 1500 ℃, and the heat preservation time is 4 to 48 hours. After annealing treatment, the final infrared transparent ceramic sheet is obtained after grinding and polishing treatment sequentially by using sand paper from small to large meshes.
Further preferably, in step S4, the annealing process includes two times, the nano-composite sintered body is subjected to the first annealing process, then placed in a hot isostatic pressing sintering furnace, sintered through the hot isostatic pressing sintering process, applied pressure is 150-200 MPa, sintering temperature is 1500-1850 ℃, and heat preservation time is 2-10 hours, and then subjected to the second annealing process, so as to obtain the infrared transparent ceramic material. And the sintering is carried out twice, so that air holes can be further eliminated, the densification of the ceramic material is facilitated, and the optical light transmittance and the mechanical property are improved.
Further, in step S1, the nano-composite powder may be prepared by any one of a solid phase method, a co-precipitation method, a uniform co-precipitation method, a hydrothermal method, a sol-gel method, or a combustion method, specifically as follows:
firstly, synthesizing the nano composite powder by adopting a solid phase method, which comprises the following substeps:
a1, weighing the raw materials according to the dosage ranges of the Y, Mg and Gd elements defined above, and mixing the raw materials by wet ball milling to obtain a mixed material. Wherein the dispersion medium is absolute ethyl alcohol, the ball milling speed is 150-300 r/min, and the ball milling time is 10-50 h.
a2, drying, grinding, sieving and granulating the mixed material to obtain a powder mixture. Wherein the drying temperature is 60-120 ℃, and the powder is sieved by a 200-mesh sieve.
a3, calcining the powder mixture in air or oxygen calcining atmosphere at 400-1350 ℃, at a heating rate of 2-5 ℃/min and for 2-6 h to obtain the nano composite powder.
Secondly, synthesizing the nano composite powder by adopting a coprecipitation method, which comprises the following substeps:
b1, weighing the raw materials according to the dosage ranges of the Y, Mg and Gd elements defined above, dissolving all the raw materials in the nitric acid solution, and fully dissolving the raw materials to obtain the mixed clear solution of metal ions.
b2, slowly adding a precipitator into the mixed clear solution in the stirring process, wherein all substances in the solution generate chemical reaction and generate white precipitate, and continuously stirring for several hours (generally 1-4 hours) after the dropwise addition is finished, so that the reaction is complete, and the reaction solution of the precursor is obtained. Wherein the precipitator comprises at least one of ammonia water, ammonium bicarbonate and urea, and the molar ratio of the precipitator to nitrate contained in the mixed clarified solution is 3.5-5: 1.
b3, centrifugally separating the reaction liquid, reserving the precursor precipitate, cleaning, drying, sieving and granulating the precursor precipitate to obtain precursor powder. Wherein the cleaning comprises washing with water for 2-3 times, then washing with alcohol for 2-3 times, and drying at 60-120 ℃.
And b4, calcining the precursor powder in air or oxygen calcining atmosphere at the temperature of 400-1350 ℃, at the heating rate of 2-5 ℃/min and for 2-6 h to obtain the nano composite powder.
Thirdly, the nano composite powder is synthesized by adopting a homogeneous precipitation method, and the method specifically comprises the following substeps:
c1, weighing the raw materials according to the dosage ranges of the Y, Mg and Gd elements defined above, dissolving all the raw materials in the nitric acid solution, and fully dissolving to obtain the mixed clear solution of metal ions.
And c2, adding a homogeneous precipitant into the mixed clear solution, and uniformly stirring to obtain a precursor reaction solution. Wherein the homogeneous precipitant comprises at least one of ammonia water, ammonium bicarbonate and urea, and the molar ratio of the homogeneous precipitant to nitrate contained in the mixed clarified solution is 5-30: 1.
And c3, heating the precursor reaction liquid to 80-95 ℃, and keeping the temperature and stirring for 60-240 min after white precipitates appear in the solution to obtain a suspension. Wherein, under the heating temperature of 80-95 ℃, the uniform precipitate is more favorably formed.
And c4, cooling the suspension, centrifugally separating, retaining the precursor precipitate, cleaning, drying and sieving the precursor precipitate to obtain precursor powder. Wherein, the method comprises the steps of washing for 2-3 times, then washing for 2-3 times with alcohol, and drying at 60-120 ℃.
And c5, calcining the precursor powder in the air or oxygen calcining atmosphere at the calcining temperature of 400-1350 ℃, at the heating rate of 2-10 ℃/min and for 2-6 h to obtain the nano composite powder.
Fourthly, synthesizing the nano composite powder by adopting a coprecipitation-hydrothermal method, which comprises the following substeps:
d1, weighing the raw materials according to the dosage ranges of the Y, Mg and Gd elements defined above, dissolving all the raw materials in the nitric acid solution, and fully dissolving to obtain the mixed clear solution of metal ions.
d2, dropwise adding a precipitator into the raw material mixed clear solution to enable the pH of the solution to reach 7-13, and uniformly stirring to obtain a suspension. Wherein the precipitant comprises at least one of ammonia water, ammonium bicarbonate and urea.
d3, transferring the suspension into a hydrothermal kettle, sealing the hydrothermal kettle for hydrothermal reaction at 180-240 ℃ for 8-24 h to obtain a reaction solution with the precursor.
d4, naturally cooling the reaction liquid to room temperature, and performing centrifugal separation, keeping the precursor precipitate, cleaning and drying the precursor precipitate to obtain precursor powder. Wherein the drying temperature is 60-120 ℃.
d5, calcining the precursor powder in the air or oxygen calcining atmosphere at the calcining temperature of 400-1350 ℃, the heating rate of 2-5 ℃/min and the calcining time of 2-6 h to obtain the nano composite powder.
Fifthly, synthesizing the nano composite powder by adopting a sol-gel method, which specifically comprises the following substeps:
e1, preparing yttrium nitrate solution, gadolinium nitrate solution, magnesium nitrate solution and citric acid solution with the concentration of 0.5-1 mol/L.
Specifically, the preparation process of each solution is prepared in different ways according to different actually selected raw materials, which is not limited in the present invention. For example: when raw material is selected from Y2O3MgO and Gd2O3In the preparation of the solution, the oxide powders are mixed with the nitric acid solution, and the nitrate solutions are obtained after dissolution, volume fixing and filtration. When the raw material is Y (NO)3)3·6H2O、 Mg(NO3)2·6H2O and Gd: (NO3)3·6H2And O, directly mixing the nitrate powder with deionized water to obtain the nitrate solution with the corresponding concentration. When the citric acid solution is prepared, the citric acid is obtained by dissolving citric acid powder in deionized water and mixing.
e2, mixing yttrium nitrate solution and magnesium nitrate solution according to the limited dosage range of Y, Mg and Gd elements, then adding gadolinium nitrate solution, adding citric acid solution according to the molar ratio of metal ions in the solution to citric acid being 1:1, finally adding ethylene glycol as catalyst, placing the whole mixed solution in a water bath kettle, stirring and mixing uniformly at the reaction temperature of 60-90 ℃, and carrying out complex reaction in the mixed solution to finally obtain colorless transparent gel.
e3, placing the colorless transparent gel at a foaming temperature of 180-280 ℃ and blowing air for physical foaming for 2-5 h to obtain the xerogel. Specifically, the colorless transparent gel is generally placed in an oven, which is air-blown, to physically foam the colorless transparent gel.
e4, calcining the xerogel at the calcining temperature of 450-700 ℃ to obtain white oxide mixed nano powder;
e5, performing ball milling treatment, drying and sieving on the white oxide mixed nano powder to obtain the nano composite powder.
Wherein, during ball milling treatment, absolute ethyl alcohol is used as a dispersion medium, zirconia balls are used as a ball milling medium, the mass ratio of zirconia balls to white oxide mixed nano powder is 5:1, the ball milling speed is 150-300 r/min, the ball milling time is 10-50 h, and the drying temperature is 60-120 ℃.
For the five processes for synthesizing the nano composite powder, when the calcination is carried out, the calcination temperature is less than the minimum value of each range, the decomposition of organic matters is incomplete, and the mechanical properties of the organic matters are influenced; when the calcination temperature is higher than the maximum value of each range, the sintering property of the obtained nanocomposite powder may be deteriorated, thereby affecting the subsequent sintering (i.e., step S3). Therefore, the calcination temperature for the above five processes is preferably controlled within the above range to obtain the best mechanical properties of the material.
Sixthly, synthesizing the nano composite powder by adopting a combustion method, which comprises the following substeps:
f1, weighing the raw materials according to the limited dosage ranges of the Y, Mg and Gd elements, and dissolving all the raw materials in a nitric acid solution to fully dissolve the raw materials to obtain a mixed clarified solution of metal ions;
f2, mixing the combustion agent with the mixed clear solution, and heating to above 240 ℃ to carry out violent combustion reaction. Wherein the burning agent comprises citric acid or sucrose.
f3, after the combustion reaction is finished, cooling the reaction product to obtain the nano composite powder.
The characteristics and technical effects of the preparation method of the present invention are described below with reference to specific examples. The examples, in which specific conditions are not specified, were conducted under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products available commercially.
Examples 1 to 4
In examples 1 to 4, the solid phase method was used to synthesize the nanocomposite powder, and the specific steps were similar to the above steps and were mainly performed by adjusting the process parameters of the respective steps. Examples 1-4 the process conditions for synthesizing the nanocomposite powder using the solid phase method are specifically shown in table 1 below:
table 1: process parameter conditions of examples 1 to 4
Figure BDA0001903755670000131
Examples 5 to 8
In examples 5 to 8, the above-mentioned co-precipitation method was used to synthesize the above-mentioned nanocomposite powder, and the specific steps were similar to the above-mentioned steps, and were mainly achieved by adjusting the process parameters and conditions of the respective steps. Examples 5-8 the process conditions for synthesizing the nanocomposite powder using the coprecipitation method are specifically shown in table 2 below:
table 2: process parameter conditions of examples 5 to 8
Figure BDA0001903755670000141
Examples 9 to 12
Examples 9 to 12 were performed by using the homogeneous precipitation method to synthesize the nanocomposite powder, and the specific steps were similar to the above steps, and were mainly performed by adjusting the process parameters and conditions of the respective steps. Examples 9-12 the process conditions for synthesizing the nanocomposite powder using the homogeneous precipitation method are specifically shown in table 3 below:
table 3: process parameter conditions for examples 9 to 12
Figure BDA0001903755670000142
Figure BDA0001903755670000151
Examples 13 to 16
Examples 13 to 16 were performed by using the above co-precipitation-hydrothermal method to synthesize the above nanocomposite powder, and the specific steps were similar to the above steps, and were mainly performed by adjusting the process parameters and conditions of the respective steps. Examples 13-16 the process conditions for synthesizing the nanocomposite powder using the hydrothermal method are specifically shown in table 4 below:
table 4: process parameter conditions for examples 13 to 16
Figure BDA0001903755670000161
Examples 17 to 20
In examples 17 to 20, the above-mentioned sol-gel method was used to synthesize the above-mentioned nanocomposite powder, and the specific steps were similar to the above-mentioned steps, and were mainly achieved by adjusting the process parameters and conditions of the respective steps. Examples 17 to 20 the process conditions for synthesizing the nanocomposite powder by the sol-gel method are specifically shown in table 5 below:
table 5: process parameter conditions for examples 17 to 20
Figure BDA0001903755670000162
Figure BDA0001903755670000171
Examples 21 to 23
Examples 21 to 23 were carried out under the same conditions as in example 20 except that the gadolinium nitrate solutions of examples 21 to 23 were added in amounts corresponding to Gd in the general formula2O3The amounts of (A) and (B) are 5 mol%, 10 mol% and 15 mol%, respectively.
Examples 24 to 27
Examples 24 to 27 were carried out by synthesizing the nanocomposite powder by the combustion method, and the specific steps were similar to the above steps and were mainly carried out by adjusting the process parameters and conditions of the respective steps. Examples 24-27 the process conditions for synthesizing the nanocomposite powder using the combustion method are specifically shown in table 6 below:
table 6: process parameter conditions for examples 24 to 27
Figure BDA0001903755670000181
Examples 28 to 30
Examples 28 to 40 were carried out by using the above-mentioned method for preparing an infrared transparent ceramic material, and the specific steps were similar to the above-mentioned steps, and were mainly carried out by adjusting the process parameter conditions of the respective steps. Examples 28-40 the process conditions for preparing infrared transparent ceramic materials using the above method for preparing infrared transparent ceramic materials are specifically shown in table 7 below:
table 7: process parameter conditions for examples 28 to 40
Figure BDA0001903755670000182
Figure BDA0001903755670000191
Figure BDA0001903755670000201
EXAMPLE 41
Example 41 is identical to example 28 in other conditions except that step S4:
in example 41, after the vacuum sintering in step S3 and the annealing in step S4, the infrared transparent ceramic material was sintered by the hot isostatic pressing sintering process at 1550 ℃ for 2 hours under 150MPa, and then annealed in an air atmosphere at 1200 ℃ for 24 hours, thereby obtaining an infrared transparent ceramic material.
Example 42
Example 42 is identical to example 31 in other conditions except that step S4:
in example 42, after the SPS sintering in step S3 and the annealing in step S4, the infrared transparent ceramic material was sintered by the hot isostatic pressing sintering process at 1600 ℃ and 15 hours of holding time under 200MPa, and then subjected to the second annealing in an air atmosphere at 1200 ℃ and 15 hours of holding time, thereby obtaining the infrared transparent ceramic material.
Example 43
Example 43 is identical to example 36 in other conditions except that step S3:
in example 42, after hot press sintering in step S3, secondary sintering was performed by a hot isostatic pressing sintering process at 1600 ℃, for 12 hours, and under 200MPa applied pressure.
Example 44
Example 44 is identical to example 38 in other conditions except that step S3:
in example 44, after the vacuum hot press sintering in step S3, the secondary sintering was performed by the hot isostatic pressing sintering process at 1600 ℃.
It should be noted that the method for preparing the infrared transparent ceramic material of the present invention can be implemented by combining any one of the processes for preparing the nano composite powder and any one of the sintering processes listed in the above methods, and the parameters of each process can be reasonably selected from the condition parameters listed in the above methods. Of course, the nanocomposite powder described above can also be obtained directly from commercial sources. The above embodiments are merely examples, and the present invention is not limited thereto.
Wherein, the transmission picture of the nano-composite powder prepared in the above example 22 is shown in fig. 1, and it can be seen from fig. 1 that the prepared nano-composite powder has uniform particle size distribution and the particle size is about 10 nm.
The transmittance curve of the infrared transparent ceramic material obtained in example 31 is shown in FIG. 2. it can be seen from FIG. 2 that the material has a transmittance of 70 to 80% in the mid-infrared region. Meanwhile, the hardness of the infrared transparent ceramic sheet obtained by grinding and polishing the infrared transparent ceramic material obtained in example 31 was measured, and the hardness thereof was about 10.2 GPa.
The transmittance curve of the infrared transparent ceramic material prepared in the above example 32 is shown in fig. 3, and it can be seen from fig. 3 that the transmittance at 2-6.5 μm is about 81%, which substantially meets the use requirement. Meanwhile, the hardness of the infrared transparent ceramic sheet obtained by grinding and polishing the infrared transparent ceramic material obtained in example 32 was measured, and the hardness thereof was about 11.1 GPa.
The back scattering picture of the infrared transparent ceramic material prepared in the above example 34 is shown in fig. 4, and it can be seen from fig. 4 that the grain size is about 200nm, the two phases are uniformly distributed, and pores are observed.
A real figure of the infrared transparent ceramic sheet obtained by grinding and polishing the infrared transparent ceramic material obtained in example 35 is shown in fig. 5.
The hardness chart of the infrared transparent ceramic sheet obtained by grinding and polishing the infrared transparent ceramic material obtained in the above example 35 is shown in fig. 6, and it can be seen from fig. 6 that the maximum hardness can reach 11.15 GPa.
Comparative example 1
Comparative example 1 was identical to example 31 in other conditions except that only Y was used as the starting material2O3And MgO, not doped with Gd2O3. Through detection, the transmittance in the middle infrared region is 65%, which is slightly less than 70-80% of that in example 31. Meanwhile, the hardness of the ceramic sheet obtained by grinding and polishing the ceramic material obtained in comparative example 1 was measured to be about 6.5GPa, which is less than the hardness of the ceramic sheet obtained in example 31 by 10.2 GPa.
Comparative example 2
Comparative example 1 was identical to example 32 in all other conditions except that only Y was used as the starting material2O3And Mg (NO)3)2·6H2O, not doped with Gd2O3. The detection proves that the transmittance at 2-6.5 mu m is about 75 percent and is slightly less than 81 percent of that of the embodiment 32. Meanwhile, the hardness of the ceramic sheet obtained by grinding and polishing the ceramic material obtained in comparative example 2 was measured to be about 6.8GPa, which is less than the hardness of the ceramic sheet obtained in example 32 by 11.1 GPa.
It can also be seen from the above comparative examples that Gd was doped2O3The obtained ceramic material is not doped with Gd2O3Compared with the obtained ceramic material, the transparent ceramic material has high transmittance and can further improve the mechanical property of the transparent ceramic material.
In conclusion, the nano composite powder prepared by any one of the methods has low cost, the nano composite powder synthesized under the parameter conditions is extremely fine, the three phases are uniformly and stably distributed, the sintering activity is high, and the microstructure is very stable and no impurity phase is generated in each sintering process. And any method for preparing the nano composite powder is simple to operate, does not need a precise instrument and is easy to realize industrial production. This lower cost process can be easily used to synthesize other oxide/oxide composites.
Hair brushThe process for preparing the infrared transparent ceramic material is carried out under the conditions of the sintering parameters and Gd2O3Can provide enough sintering power. Due to Gd during sintering2O3The addition of the crystal grain size can inhibit the diffusion speed of a crystal boundary, reduce the growth speed of crystal grains, is more beneficial to densification, simultaneously reduces the crystal grain size, has no influence on the transmittance of the transparent ceramic material, has the crystal grain size of 60-600 nm, achieves more than 99.2 percent of theoretical sintering density, meets the optical properties of infrared transmission, low signal-to-noise ratio and the like, simultaneously considers the mechanical and mechanical properties of the transparent ceramic material, has the highest product hardness of 11.15GPa, and obtains the transparent ceramic material with the properties of high density, high transmittance and high hardness. The invention is successfully beneficial to the upgrade of domestic infrared window materials, and makes a solid step for meeting the requirements of future ultra-high Mach number missiles on the infrared window/fairing.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not intended to limit the present invention in any way, so that any person skilled in the art can make modifications or changes in the technical content disclosed above. However, any simple modification, equivalent change and modification of the above embodiments according to the technical essence of the present invention are within the protection scope of the technical solution of the present invention.

Claims (9)

1. An infrared transparent ceramic material is characterized in that the general formula of the infrared transparent ceramic material is as follows: y is2O3-MgO-Gd2O3；
The infrared transparent ceramic material is prepared by adopting a material containing Y2O3Nano-powder of (2), nano-powder of MgO and Gd2O3The nano composite powder body composed of the nano powder is fired;
wherein, in the nano-composite powder, Y2O3The volume ratio of the nano-powder of (A) to the nano-powder of MgO is 1:1, Gd2O3The nano powder accounts for 0.01 to 18 percent of the total molar weight of the nano composite powder;
the preparation method of the infrared transparent ceramic material comprises the following steps:
s1, preparing the nano-composite powder by adopting a raw material containing Y, a raw material containing Mg and a raw material containing Gd;
wherein the raw material containing Y is oxide, salt or crystalline hydrate of salt of Y, the raw material containing Mg is oxide, salt or crystalline hydrate of Mg, and the raw material containing Gd is oxide, salt or crystalline hydrate of salt of Gd;
s2, carrying out compression molding treatment on the nano composite powder obtained in the step S1 to obtain a molded biscuit;
s3, sintering the molded biscuit to obtain a nano composite sintered body;
s4, annealing the nano composite sintered body to obtain the infrared transparent ceramic material;
in the step S3, the sintering treatment adopts a vacuum sintering process, the sintering temperature is 1500-1850 ℃, and the heat preservation time is 0.1-15 h; or
In step S3, the sintering treatment adopts a hot-pressing sintering process, the sintering temperature is 1200-1400 ℃, and the heat preservation time is 0.5-5 h; or
In step S3, the sintering treatment adopts a spark plasma sintering process, the sintering temperature is 1100-1400 ℃, and the heat preservation time is 0.2-1 h; or
In step S3, the sintering process adopts a vacuum hot-pressing sintering process, the sintering temperature is 1300-1800 ℃, and the heat preservation time is 0.5-5 h;
in step S4, the annealing atmosphere of the annealing treatment includes air or oxygen, the annealing temperature is 1100 to 1500 ℃, and the heat preservation time is 4 to 48 hours.
2. The infrared transparent ceramic material of claim 1,
the Gd2O3The percentage of the nano powder in the total molar amount of the nano composite powder is 5-15%.
3. A process for the preparation of an infrared transparent ceramic material according to claim 1 or 2, comprising the steps of:
s1, preparing the nano-composite powder by adopting a raw material containing Y, a raw material containing Mg and a raw material containing Gd;
wherein the raw material containing Y is oxide, salt or crystalline hydrate of salt of Y, the raw material containing Mg is oxide, salt or crystalline hydrate of Mg, and the raw material containing Gd is oxide, salt or crystalline hydrate of salt of Gd;
s2, carrying out compression molding treatment on the nano composite powder obtained in the step S1 to obtain a molded biscuit;
s3, sintering the molded biscuit to obtain a nano composite sintered body;
s4, annealing the nano composite sintered body to obtain the infrared transparent ceramic material;
in the step S3, the sintering treatment adopts a vacuum sintering process, the sintering temperature is 1500-1850 ℃, and the heat preservation time is 0.1-15 h; or
In step S3, the sintering treatment adopts a hot-pressing sintering process, the sintering temperature is 1200-1400 ℃, and the heat preservation time is 0.5-5 h; or
In step S3, the sintering treatment adopts a spark plasma sintering process, the sintering temperature is 1100-1400 ℃, and the heat preservation time is 0.2-1 h; or
In step S3, the sintering process adopts a vacuum hot-pressing sintering process, the sintering temperature is 1300-1800 ℃, and the heat preservation time is 0.5-5 h;
in step S4, the annealing atmosphere of the annealing treatment includes air or oxygen, the annealing temperature is 1100 to 1500 ℃, and the heat preservation time is 4 to 48 hours.
4. The process for preparing an infrared transparent ceramic material according to claim 3,
in the step S3, after the nano composite sintered body is obtained, sintering the nano composite sintered body by a hot isostatic pressing sintering process, wherein the sintering temperature is 1500-1850 ℃, the heat preservation time is 2-10 hours, and then entering the step S4; and/or
In the step S4, the annealing process includes two times, the nano composite sintered body is subjected to the first annealing process, then is sintered by the hot isostatic pressing sintering process at the sintering temperature of 1500-1850 ℃ for 2-10 hours, and then is subjected to the second annealing process to obtain the infrared transparent ceramic material.
5. The method for preparing an infrared transparent ceramic material according to any one of claims 3 to 4, wherein in step S1, the method for synthesizing the nano composite powder by a solid phase method comprises the following steps:
a1, weighing the raw materials according to the dosage range of Y, Mg and Gd elements defined in claim 1, and mixing the raw materials by wet ball milling to obtain a mixed material;
a2, drying, grinding, sieving and granulating the mixed material to obtain a powder mixture;
a3, calcining the powder mixture at the temperature of 400-1350 ℃ for 2-6 h to obtain the nano composite powder.
6. The process for the preparation of an infrared transparent ceramic material according to any one of claims 3 to 4,
in step S1, a mixed clarified solution of metal ions is obtained from a Y salt, a Mg salt, and a Gd salt, and then a precursor powder of precipitates containing these metal elements is prepared from the mixed clarified solution of metal ions, and the precursor powder is calcined to obtain the nanocomposite powder.
7. The method for preparing an infrared transparent ceramic material according to claim 6,
the precursor of the precipitate is prepared by adopting a coprecipitation method or a coprecipitation-hydrothermal method, wherein the calcining temperature is 400-1350 ℃, and the calcining time is 2-6 h.
8. The process for the preparation of an infrared transparent ceramic material according to any one of claims 3 to 4,
in step S1, synthesizing the nanocomposite powder by a sol-gel method, specifically including the steps of:
e1, preparing yttrium nitrate solution, gadolinium nitrate solution, magnesium nitrate solution and citric acid solution with the concentration of 0.5-1 mol/L;
e2, mixing yttrium nitrate solution and magnesium nitrate solution according to the dosage range of Y, Mg and Gd elements defined in claim 1, then adding gadolinium nitrate solution, adding citric acid solution according to the molar ratio of metal ions in the solution to citric acid being 1:1, finally adding catalyst ethylene glycol, placing the whole mixed solution at 60-90 ℃ and uniformly mixing to obtain colorless transparent gel;
e3, placing the colorless transparent gel at 180-280 ℃ and blowing air for physical foaming to obtain dry gel;
e4, calcining the xerogel at the calcining temperature of 450-700 ℃ to obtain white oxide mixed nano powder;
e5, performing ball milling treatment, drying and sieving on the white oxide mixed nano powder to obtain the nano composite powder.
9. The process for the preparation of an infrared transparent ceramic material according to any one of claims 3 to 4,
in step S1, the synthesis of the nanocomposite powder by a combustion method specifically includes the following steps:
f1, weighing the raw materials according to the dosage range of the Y, Mg and Gd elements defined in the claim 1, and dissolving all the raw materials in nitric acid solution to obtain mixed clarified solution of metal ions;
f2, mixing a combustion agent with the mixed clear solution, and heating to above 240 ℃ for combustion reaction;
f3, after the combustion reaction is finished, cooling the reaction product to obtain the nano composite powder.
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CN110342907B (en) * 2019-07-22 2023-02-14 中国科学院上海光学精密机械研究所 Preparation method of Y2O3-MgO nano complex phase infrared ceramic
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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4571312A (en) * 1982-06-18 1986-02-18 General Electric Company Preparation of yttria-gadolinia ceramic scintillators by sintering and gas hot isostatic pressing
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US5116559A (en) * 1991-02-26 1992-05-26 General Electric Company Method of forming yttria-gadolinia ceramic scintillator using hydroxide coprecipitation step
CN101555128A (en) * 2003-01-20 2009-10-14 宇部兴产株式会社 Ceramic composite material for optical conversion and use thereof
CN102190499A (en) * 2010-03-18 2011-09-21 中国科学院福建物质结构研究所 Preparation method of transparent yttria ceramic
CN103922742B (en) * 2014-04-02 2016-02-10 中国科学院上海硅酸盐研究所 A kind of Y 2o 3-MgO nano heterogeneous ceramic and preparation method thereof
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