203 results about "Transparent ceramics" patented technology

The invention discloses a color-permeable colorful ceramic and a preparation process thereof, and belongs to the technical field of ceramic preparation processes, a transparent AlON ceramic body is formed by low-temperature diffusion bonding sintering, an adjustable structural color of 480-630 nm is realized through TiO2 / ZrO2 nanocrystalline spacing (180-220 nm), a Sm2O3 chemical color is superposed, delta E is less than or equal to 0.5, and the color is changed along with the angle and does not fade; after decoration firing of a finished product, embossment line patterns can be engraved inside and outside the ceramic body through femtosecond laser, due to the fact that the main body of the ceramic body is high in light transmittance, when light directly irradiates or enters the interior from the top as a bottle, halo of the embossment line patterns engraved inside and outside can be scattered on the surface, and the overall optical effect is improved; the ceramic is suitable for high-grade decorative ceramics such as bottles and ornaments.

It is described a process for producing transparent ceramic bodies with at least two zones having different garnet composition, in particular in which one of said zones has composition Y3AI5O12. The invention is especially useful for the production of transparent ceramic bodies having preset complex shapes and / or a controlled complex distribution of doping ions.

The invention discloses a Joule heat heating-based YAG transparent ceramic rapid welding method, and belongs to the technical field of welding. According to the method, a Joule heat ultra-fast high-temperature heating method is utilized, and a glass solder is adopted for connecting YAG transparent ceramics, so that a joint with high strength and high light transmittance is obtained. The method specifically comprises the following steps: carrying out grinding and polishing treatment on the YAG ceramic surface; the preparation method comprises the following steps: weighing oxide raw materials according to the composition of the glass material, uniformly mixing, and preparing glass powder by adopting a melting-water quenching method; preparing the glass powder into slurry, and uniformly coating the surface of the transparent YAG ceramic with the slurry; and placing in an ultra-fast high-temperature sintering furnace for connection. According to the Joule heat ultra-fast high-temperature connection YAG transparent ceramic, connection is completed within one minute through the fast heating and cooling process, a connector with high strength and high light transmittance is obtained, and the production efficiency is greatly improved.

The invention discloses a near-net-shape preparation process of high-light-transmittance large-size magnesium aluminate spinel ceramic, and belongs to the technical field of preparation of high-performance transparent ceramic. The process comprises the following steps: firstly, mixing magnesium aluminate spinel raw material powder with a lithium-free composite sintering aid according to a mass ratio, wherein the composite sintering aid consists of magnesium fluoride, ytterbium fluoride and ytterbium oxide according to a molar ratio; performing cold isostatic pressing on the mixed powder to prepare a preformed blank, crushing, and performing high-low pressure circulation pressurization near-net forming. The obtained green body is firstly subjected to hot pressing and presintering, then placed in a fluorine-containing atmosphere to be treated and finally subjected to hot isostatic pressing sintering, and a finished product is obtained through aftertreatment. According to the technology, the bottleneck of large-size component preparation is successfully overcome, net forming of the magnesium aluminate spinel ceramic with the diagonal size larger than 400 mm is achieved, the light transmittance of a finished product in the wavelength range of 400 nm to 800 nm exceeds 93%, the breaking strength reaches 194 MPa or above, and meanwhile the raw material cost and equipment dependence are remarkably reduced.

The invention belongs to the technical field of transparent ceramics and electronic packaging materials, and particularly relates to a low-thermal-expansion-coefficient transparent glass ceramic and a preparation method thereof. The base glass is prepared from the following components in percentage by mass: 60 to 65 percent of SiO2, 20 to 25 percent of Al2O3 and 4 to 10 percent of Li2O, the mass ratio of Li2O to Al2O3 is 0.22 to 0.3, the mass ratio of Li2O to SiO2 is 0.08 to 0.1, and the mass ratio of Al2O3 to SiO2 is 0.33 to 0.5; 2%-5% of a sintering aid B2O3; the nucleating agent at least comprises ZrO2, and the proportion of the components in the total raw materials is as follows: 1%-5% of ZrO2, 0%-3% of ZnO, 0%-3% of TiO2, 0%-1% of P2O5, 0%-4% of Al2TiO5 and 0%-3% of (BaO + CaO + SrO); the Al2TiO5 and the TiO2 are not used at the same time; the doping substance is a mixture of La2O3 and CeO2 and accounts for 0.5%-1% in total; and the clarifying agent is a mixture of SnO2 and CaF2 and accounts for 0.5%-1% in total. The preparation method comprises the steps of raw material melting and water quenching, grinding and sieving, granulation forming, sintering by a three-step sintering method, ion exchange treatment and the like, and finally the transparent glass ceramic with low thermal expansion coefficient, high light transmittance and high bending strength can be obtained.

The invention belongs to the technical field of transparent ceramics, and discloses a high-entropy transparent ceramic and a preparation method and application thereof. The molecular formula of the high-entropy transparent ceramic is (LuxYySczYbmErn) 2O3, x is more than or equal to 0.05 and less than or equal to 0.6, y is more than or equal to 0.05 and less than or equal to 0.6, z is more than or equal to 0.05 and less than or equal to 0.6, m is more than or equal to 0.05 and less than or equal to 0.6, n is more than or equal to 0.05 and less than or equal to 0.6, and x + y + z + m + n is equal to 1, Lu2O3 powder, Y2O3 powder, Sc2O3 powder, Yb2O3 powder, Er2O3 powder and ZrO2 powder are subjected to ball milling and mixing, calcined and molded at 800-1200 DEG C to prepare a biscuit, and the biscuit is subjected to pressureless sintering at 1600-1800 DEG C in vacuum, annealed and polished to prepare the high The relative density of the ceramic is 99.5% or above, the transmittance at 1000 nm is 76% or above, and the ceramic has good optical, mechanical, corrosion-resistant and radiation-resistant performance and can be applied to the field of nuclear energy window material preparation.

The invention is suitable for the technical field of ceramic materials, and relates to lanthanum calcium sulfide transparent ceramic powder and a preparation method thereof. Comprising the following steps: weighing nitrate containing La and Ca according to a certain molar ratio, respectively dissolving into deionized water, and uniformly mixing to obtain a solution A; adding a citric acid solution into the solution A, adjusting the pH value with ammonia water, and stirring to obtain a mixed solution; the mixed solution is heated and stirred for a period of time, white transparent sol is formed through hydrolysis and polymerization reaction, and then the sol is placed in a drying box to be dehydrated into dry gel; heating the dried gel at high temperature to obtain lanthanum calcium sulfide precursor powder; and putting the lanthanum-calcium sulfide precursor powder into a tubular furnace, and vulcanizing in a sulfur-containing atmosphere to obtain the lanthanum-calcium sulfide powder. The method has the beneficial effects that the operation steps are simple, and the production cost and the production difficulty are effectively reduced. And gel organic components are removed by means of spontaneous combustion treatment, and the raw material proportion and reaction conditions are accurately controlled, so that the powder purity is greatly improved. In the hydrolysis and polymerization reaction, citric acid complexation is utilized and reaction conditions are strictly controlled, so that the particle size of the powder is uniform, the dispersity is good, and the transparency, the mechanical property and the optical property of the transparent ceramic are improved. Besides, by adjusting parameters such as raw material proportion, solution pH value, reaction temperature and time and the like, the performance of the powder is flexibly regulated and controlled, and diversified requirements on the performance of the lanthanum calcium sulfide ceramic powder in different application scenes are met.

The invention discloses preparation and application of YAG transparent ceramic suspension for plasma spraying, Y2O3 powder with high purity of 99.99% is selected to be prepared into slurry, the slurry is ball-milled, centrifuged, dried and sieved to obtain Y2O3 powder, the obtained Y2O3 powder and Al2O3 powder with high purity of 99.99% are weighed according to a stoichiometric ratio of Y3Al5O12 to prepare mixed slurry, spray granulation, calcination, dry grinding and sieving are carried out, and the YAG transparent ceramic suspension for plasma spraying is obtained. And the obtained powder is prepared into suspension liquid for plasma spraying. The YAG transparent ceramic serves as a plasma spraying coating, is high in hardness and can effectively resist scraping and abrasion of external objects, the abrasion resistance of the surfaces of the coated objects is enhanced, and the service life is prolonged. The supersonic plasma spraying technology is adopted, preparation of the YAG transparent ceramic coating which is high in density, low in porosity, uniform in structure and high in hardness is achieved, and physical and chemical reactions occurring in the long-term service process of the Y2O3 coating material are avoided.

The invention discloses a method for preparing high-transparency yttrium iron garnet ceramic by combining a chemical synthesis way with pressureless sintering. The method comprises the following steps: synthesizing submicron alpha-iron oxide powder; forming the powder; and carrying out pressureless sintering in an oxygen atmosphere. The YIG transparent ceramic prepared in the invention has very high transmittance (the highest transmittance is 40% at 1.5 m) in an infrared band, and the YIG transparent ceramic with high optical quality (the transmittance is as high as 75% at 1.5 m) can be obtained by combining oxygen hot isostatic pressing sintering. And the preparation process is simple, the synthesis conditions are easy to control, the material synthesis period is short, energy and cost are saved, and the requirements of industrial production are met.

The invention discloses an infrared transparent ceramic material with a wide transmission wave band and a preparation method of the infrared transparent ceramic material, and belongs to the field of inorganic ceramic materials. The chemical formula of the infrared transparent ceramic material is (Y < 1-x >, Re < x >) 2O3-(Mg < 1-y > Re < y >) O, and x is more than 0 and less than 4%; 0 < y < 30%; re is one of Zn < 2 + >, Mn < 2 + > and Ni < 2 + >; the preparation method of the infrared transparent ceramic material comprises the following steps: firstly, preparing primary Y2O3-(Mg1-yRey) O powder; placing the powder and a binder in a ball milling tank, adding a solution of a compound of Re < 2 + > with the molar percentage of x, and carrying out ball milling to obtain slurry; drying, crushing, sieving and calcining the slurry to obtain (Y < 1-x >, Re < x >) 2O3-(Mg < 1-y > Re < y >) O powder; the preparation method comprises the following steps: performing equiaxial bidirectional pressure forming on Y2O3 nano powder, then adding (Y < 1-x >, Re < x >) 2O3-(Mg < 1-y > Re < y >) O powder for forming, and then adding Y2O3 nano powder for forming to obtain a ceramic biscuit with a composite structure; and performing double-sided laser sintering on the ceramic biscuit, removing Y2O3 on the upper surface layer and the lower surface layer, and performing double-sided polishing treatment to obtain the infrared transparent ceramic material. The biscuit composite structure design and the laser sintering technology are adopted, the oxygen vacancy defect generated by traditional sintering can be effectively avoided, therefore, an air annealing technology is not needed, and meanwhile the problems that the valence state of Re < 2 + > is unstable and oxidation is prone to occurring are effectively avoided. The densification of the multiphase ceramic is realized in an extremely short time by laser sintering, the grain size is effectively inhibited, the grain scattering is avoided, and the near-infrared transmittance of the ceramic is improved.

The invention belongs to the technical field of new materials, and discloses a composite material, a preparation method thereof and automobile glass, the composite material is a curved surface, and comprises a composite matrix, a glass plate and an organic back plate from bottom to top in sequence; wherein the composite matrix comprises a plurality of transparent ceramics and a glass matrix, and the plurality of transparent ceramics are spliced and laid in the glass matrix to form a structure that the glass is filled with the transparent ceramics. According to the invention, glass is taken as a matrix, a plurality of transparent ceramics are taken as filling bodies to form a composite matrix structure of partitioned transparent ceramic filled glass, and the composite matrix structure is compounded with a glass plate and an organic back plate, so that the composite material of the curved transparent ceramic filled glass with high safety, light weight, large size (1000mm * 1800mm) is obtained, the light transmittance is 64.2-81.2%, and the bending strength reaches 168.4-213.7 MPa.

The invention is suitable for the technical field of ceramic materials, and relates to lanthanum calcium sulfide transparent ceramic powder with wide spectrum transmittance and a preparation method of the lanthanum calcium sulfide transparent ceramic powder. The preparation method specifically comprises the following steps: weighing nitrate containing La and Ca according to a specific molar ratio, respectively dissolving the nitrate containing La and Ca into deionized water, and fully mixing to obtain a solution A; adding a thiourea solution into the solution A, and stirring to obtain a mixed solution; heating and continuously stirring the mixed solution, and carrying out hydrolysis and polymerization reaction to form white sol; then, the sol is placed in a drying oven to be subjected to dehydration treatment until the sol is converted into dry gel; and heating the dried gel at high temperature to obtain lanthanum calcium sulfide precursor powder. And putting the lanthanum-calcium sulfide precursor powder into an atmosphere furnace, and carrying out vulcanization reaction in a sulfur-containing atmosphere to prepare the lanthanum-calcium sulfide powder. The preparation method has the advantages that the operation process is simple, the prepared powder is uniform in particle size, high in purity and excellent in dispersity, and the optical performance of the transparent ceramic can be improved.

The invention discloses a method for preparing YAG transparent ceramic by two-step sintering, which comprises the following steps: 1) weighing yttrium oxide powder and aluminum oxide powder according to a stoichiometric ratio, mixing, and carrying out solid-phase reaction to synthesize YAG powder; 2) performing dry grinding and wet grinding on the obtained YAG powder to obtain mixed slurry; 3) drying the obtained mixed slurry to obtain powder, and performing compression molding and cold isostatic pressing to obtain a ceramic biscuit; and 4) pre-sintering the obtained ceramic biscuit in an oxygen-containing atmosphere, embedding the pre-sintered ceramic with oxide particles, and carrying out hot isostatic pressing sintering to prepare the YAG transparent ceramic. On the basis of obtaining the YAG transparent ceramic with high optical quality, a microstructure with a fine grain size can be obtained, and good mechanical properties are considered; the preparation method is simple, the equipment cost and energy consumption are low, the traditional annealing step can be omitted, and a new thought can be provided for preparation of the high-performance YAG transparent ceramic.

The invention discloses a low infrared absorption coefficient Y2O3 transparent ceramic and a preparation method thereof, and the preparation method comprises the following steps: carrying out dry pressing molding on Y2O3 powder, and carrying out cold isostatic pressing treatment to obtain a ceramic biscuit; the ceramic biscuit is subjected to glue discharging at the temperature of 600-1250 DEG C; carrying out vacuum heat treatment on the biscuit subjected to glue removal under the conditions that the vacuum degree is less than or equal to 10 Pa and the temperature is 400-1550 DEG C so as to remove residual hydroxyl; pre-burning the sample subjected to vacuum heat treatment in air or oxygen; and carrying out hot isostatic pressing sintering on the pre-sintered sample to realize ceramic densification so as to obtain the Y2O3 transparent ceramic. By adopting the preparation method disclosed by the invention, an expensive high-vacuum sintering furnace does not need to be arranged, and pre-sintering of the Y2O3 transparent ceramic can be completed by using a simple atmosphere sintering furnace, so that the Y2O3 transparent ceramic with high optical quality is obtained.

The invention discloses a manganese-doped aluminum-rich magnesium aluminate spinel transparent ceramic phosphor which is of a single-phase magnesium aluminate spinel structure, and the stoichiometric formula is Mg (1-x-y) Al (2 + 2x) / 3O4: yMn, x is greater than or equal to 0.004 and less than or equal to 0.1; the preparation method comprises the following steps: firstly, preparing Mg1-x-yAl2 + 2x / 3O4: yMn single-phase ceramic powder by adopting a high-temperature solid-phase reaction, and then carrying out dry-pressing molding, pressureless pre-sintering and hot isostatic pressing treatment to obtain the high-temperature-resistant magnesium alloy. The transparent ceramic phosphor is of a block structure and has the advantages of being high in optical quality, narrow in half-peak width emission, high in thermal stability, high in thermal conductivity and the like. The high-power white-light LED packaging material can effectively replace a traditional mode of packaging powder through organic glue, is beneficial to solving the problems of heat dissipation and light efficiency conversion, is expected to improve the stability of an LED device, solves the problems of fluorescence performance reduction and the like caused by aging of plastic packaging glue in the using process of a high-power white-light LED, and is suitable for popularization and application.

This invention discloses a YAG-based composite laser ceramic and its preparation method. The composite laser ceramic has a five-layer structure from top to bottom: a microstructured concave YAG transparent ceramic, an Nd:YAG transparent ceramic, a YAG transparent ceramic I, a Ce,Nd:YAG transparent ceramic, and a YAG transparent ceramic II. The microstructured concave YAG transparent ceramic is used to reduce the temperature gradient and compensate for the thermal lensing effect; the Nd:YAG transparent ceramic is used to collect the energy emitted by the microstructured concave YAG transparent ceramic and to transfer the energy; the Ce,Nd:YAG transparent ceramic is used for laser energy transfer; and the YAG transparent ceramic I and YAG transparent ceramic II are used to reduce the ceramic thermal lensing effect. It is prepared using thermal bonding technology. The composite laser ceramic of this invention emits bright yellow light near 1064 nm when excited by a laser with a pump source of 808 nm. Furthermore, the composite laser ceramic has a light-to-light conversion efficiency of 19.85% and a laser threshold of 410 mW.

The invention discloses a lutetium-calcium-magnesium-aluminum-silicon garnet transparent ceramic material and application thereof in a white-light LED (light-emitting diode). The method comprises the following steps: (1) fusing SiO2, Al2O3, Lu2O3, CaO, MgO and raw materials doped with luminous ions to obtain glass liquid; (2) molding, cooling and annealing the molten glass to obtain a glass precursor; 3) performing heat treatment on the glass precursor to obtain the lutetium calcium magnesium aluminum silicon garnet ceramic; and luminous ions are more than one of Ce, Er, Nd and Cr. The method is simple, the prepared ceramic is good in luminescent property, high in heat conductivity and high in hardness, and the preparation method is simple and low in cost. The method can be used for preparing transparent ceramics with large sizes and various shapes, and is low in cost and easy for industrial production. The ceramic emits bright yellow light under the excitation of 450nm blue light, and the yellow light and the blue light are combined to generate strong white light, so that the ceramic can be used for preparing a white light LED (light-emitting diode).

The present invention relates to a method for manufacturing a transparent ceramic three-dimensional structure using 3D printing and, specifically, to a method for manufacturing a transparent ceramic three-dimensional structure using 3D printing, the method comprising the steps of: preparing transparent ceramic particles; supplying a 3D printing slurry containing the transparent ceramic particles and a photocurable resin onto a 3D device plate and then irradiating same with light to form a printing layer, and forming a three-dimensional printing structure by repeating the process of forming the printing layer; sintering the three-dimensional printing structure; and polishing the surface of the sintered structure, wherein the maximum diameter of the transparent ceramic particles is less than or equal to the thickness of the printing layer, and the surface polishing step is a chemical-mechanical composite polishing step.

The invention provides a preparation method of low-scattering magnesium aluminate spinel transparent ceramic, which comprises the following steps: powder purification and dispersion: carrying out acid pickling and impurity removal on magnesium aluminate spinel raw powder, and carrying out centrifugal separation to obtain wet powder; the wet powder, grinding balls and deionized water are mixed and subjected to ball milling, and ceramic slurry containing the grinding balls is obtained; freeze drying and morphology modification: performing freeze drying on the ceramic slurry to obtain fluffy powder; the fluffy powder and the grinding balls are subjected to vibration screening, the powder morphology is modified, the grinding balls are separated, and modified powder with improved fluidity is obtained; dynamic pressure forming: filling a sheath with the modified powder, and applying fluctuation type dynamic pressure under a cold isostatic pressing condition to obtain a biscuit; the dynamic pressure promotes particle rearrangement until the density of the biscuit is saturated by alternately switching high pressure and low pressure and circularly applying pressure; and densification treatment: sequentially carrying out vacuum sintering and hot isostatic pressing treatment on the biscuit to obtain the low-scattering transparent ceramic.

The invention relates to a preparation method of NaLnS2 transparent ceramic powder with high infrared light transmittance, which comprises the following steps: by taking rare earth polysulfide LnS2 powder as a raw material and sodium fluoride or sodium sulfide as an additive, mixing the raw material and the additive to prepare a precursor of the NaLnS2 ceramic powder, putting the prepared precursor powder into an improved ball milling tank, and carrying out ball milling to obtain the NaLnS2 transparent ceramic powder with high infrared light transmittance. And carrying out mechanochemical reaction in a protective gas environment, and after ball milling is finished, separating out powder to obtain the NaLnS2 transparent ceramic powder. The problem that the NaLnS2 transparent ceramic powder is easy to oxidize due to high-temperature vulcanization is solved, and the prepared NaLnS2 transparent ceramic powder is low in oxygen content and small in particle size.

The invention belongs to the technical field of multi-component garnet-based transparent ceramics, and discloses a novel multi-component garnet-based transparent ceramic for near-infrared laser. The chemical formula of the multi-component garnet-based transparent ceramic material is RE: LuxY (3-x) Al5O12. Commercial powder is adopted as a reaction raw material, an additional complex powder synthesis procedure is not needed, the difficulty and cost of raw material pretreatment are reduced, key steps such as ball milling, forming and sintering are integrated into a coherent integrated process through a high-temperature solid-phase reaction sintering method, conversion and intervention of intermediate links are reduced, and the preparation method is suitable for industrial production. Compared with the prior art, the method has the advantages that the whole technological process is simpler and clearer, standardized operation and parameter regulation and control are easy, the preparation period is greatly shortened, the production efficiency is improved, meanwhile, in the forming stage, through the mode of combining dry pressing and cold isostatic pressing, different mold designs can be flexibly adapted, preparation of large-size samples is achieved, and the regulation and control performance on the shapes of the samples is higher.

The application discloses a preparation method of high-transmittance Ce:YAG transparent ceramic, and the method comprises the following steps: taking tetraethyl orthosilicate and Al2O3 as raw materials, adding them into an ethanol solution, stirring uniformly at room temperature, heating to obtain a core-shell structure precursor, and washing and drying to obtain a core-shell structure oxide Al2O3@Si; taking Al2O3, Y2O3 and CeO2 as raw material powders, taking each raw material according to the stoichiometric ratio of corresponding elements in a chemical formula (Y 1‑x Ce x )3Al5O 12 Sintering aids, anhydrous ethanol, a dispersant, the core-shell structure oxide and the raw material powders are put into a ball mill tank to obtain a mixed slurry; the mixed slurry is sequentially subjected to drying, sieving, calcining, dry pressing, plastic packaging, sintering, annealing and polishing to obtain the transparent ceramic. The method can fill the grain boundary pores and accelerate the particle rearrangement, improve the sintering activity of the ceramic powder, thereby improving the density of the ceramic, and further improving the transmittance of the ceramic.

The invention discloses a preparation method of thermal shock resistant Nd: LuAG laser transparent ceramic. The preparation method comprises the following specific steps: weighing lutetium nitrate, aluminum nitrate and neodymium nitrate according to Lu3-xNdxAl5O12, and obtaining nano precursor powder by adopting a solvothermal method; carrying out two-step pre-sintering to form oxide powder with a sub-grain structure; and adding a thermal shock slow-release agent for main sintering, carrying out hot isostatic pressing treatment on the ceramic body after main sintering, and finally annealing in air to obtain the Nd: LuAG transparent ceramic with the density being greater than or equal to 99.9% and the thermal shock resistance temperature difference delta T being greater than or equal to 400 DEG C. The ceramics are particularly suitable for high repetition frequency laser systems.

To provide transparent ceramics that are truly transparent, have few scattering sources from visible to the near-infrared range, and are resistant to laser damage, and to provide a magnetic optical device using the same.SOLUTION: Transparent ceramics are cylindrical in shape having a surface roughness Ra of 1 nm or less on both optical surfaces, with a sample length of 20 mm. When the optical surface of the sample is placed on a black background and an image of the optical surface is acquired using 256-level grayscale, assuming that a grayscale value of the background portion is defined as GB, a highest grayscale value is defined as GH, and a grayscale average value of the central region covering 20*80% of the diameter of the optical surface is defined as GT, the following equation (1) is satisfied: (GT-GB) / (GH-GB)×100≤30%. A magneto-optical device is a light isolator that includes the above transparent ceramic as a Faraday rotator 110.SELECTED DRAWING: Figure 1

The application provides a preparation method of LiAl5O8 powder and LiAlON transparent ceramic and belongs to the technical field of transparent ceramic materials. After slurry is prepared, the preparation method is freezing drying first to obtain loose mixed material without large-particle hard agglomeration, then low-temperature solid-phase reaction is carried out, and the material is rotated and mixed every 30 minutes during the heat preservation process to realize uniform heat treatment of the material. In the application, the preparation method of the LiAl5O8 powder is a low-temperature solid-phase reaction method, and the reaction condition is simple, the cost is low, and the efficiency is high. The prepared LiAl5O8 powder is single-phase, the particle is small, the distribution is uniform, there is no large-particle agglomeration, the reaction activity is high, the dispersibility is good, and the subsequent high-energy ball milling is not needed for refinement, so the prepared LiAl5O8 powder can be directly applied to the preparation of the LiAlON transparent ceramic, and the optical transmittance of the transparent ceramic is improved.

The invention provides a preparation method of a Cr < 3 + > ion doped transparent gamma-Al2O3 luminous nano ceramic, and provides the Cr < 3 + > ion doped transparent gamma-Al2O3 luminous nano ceramic prepared by the method, and when the incident wavelength exceeds 700nm, the light transmittance is greater than 66%. The preparation method comprises the following steps: firstly, adding 1g of AlCl3 and 0-0.01 g of CrCl3. 6H2O into 40mL of absolute ethyl alcohol, and uniformly mixing; pouring the mixed solution into a reaction kettle, and carrying out sealed heat preservation at 180 DEG C for 36 hours; after the reaction is finished, collecting a product, dispersing the product in absolute ethyl alcohol and centrifuging; spreading a colloidal product obtained by centrifugation in a culture dish, and drying at 60 DEG C for 12 hours; and putting the dried small blocks into a crucible, and calcining at 800 DEG C for 1 hour to obtain the Cr < 3 + > ion doped transparent gamma-Al2O3 luminous nano ceramic. The Cr < 3 + > ion doped transparent gamma-Al2O3 ceramic prepared by the invention is a block formed by interweaving nanoribbons, and the ceramic emits red fluorescence under the irradiation of 530nm green light.

The application belongs to the field of ceramics and relates to a preparation method of transparent ceramic profiles based on laser sintering 3D printing MgAl2O4 powder, which comprises the following steps: synthesizing MgAl2O4 powder; pickling the MgAl2O4 powder; repeatedly centrifuging and washing the MgAl2O4 powder; drying, calcining, grinding and sieving the obtained precipitate to obtain pretreated MgAl2O4 powder; heating polyurethane hot melt adhesive and soluble starch to fully dissolve them, then adding ammonium citrate and deionized water to mix them, and then adding the pretreated MgAl2O4 powder to mix them, and stirring and reacting at 50-70 DEG C; spray drying to obtain granulated MgAl2O4 powder; mixing the granulated MgAl2O4 powder, ethylenediamine, zinc stearate and ABS resin and placing them in a particle grinder to grind; adding N,N-dimethylformamide to continue grinding; spray drying to obtain modified granulated MgAl2O4 powder; and using the modified granulated MgAl2O4 powder as raw material to obtain transparent ceramic profiles through laser sintering 3D printing. The method improves the machining precision and yield of transparent ceramic profiles with high precision, special shapes and complex structures, and improves the comprehensive performance of the transparent ceramic profiles.

The present invention relates to a method for rapidly pressureless sintering to prepare high-transparency AlON ceramics by adding nano-Y2O3, belonging to the field of preparation of transparent ceramic materials. A method for rapidly pressureless sintering to prepare high-transparency AlON ceramics by adding nano-Y2O3. The nano-Y2O3 powder with a high specific surface area is added as a sintering aid to the pure-phase AlON powder, and the raw materials are mixed by ball milling. The mixed powder is prepared into AlON transparent ceramics with high transparency in a wide wavelength band by pressureless sintering. Among them, the nano-Y2O3 powder with a high specific surface area is obtained by calcining yttrium acetate powder after nodular graphite in air. This method only uses a general ball milling method to achieve uniform mixing of raw materials. The sintering uses pressureless sintering technology, with easy availability of equipment and easy implementation of technology. The heat preservation time in the sintering process is short, with good energy-saving effect, high efficiency, low preparation cost, and easy industrialization.

This invention discloses an infrared optical frequency conversion element and a converter and laser using the same. It employs a nonlinear optical polycrystalline transparent ceramic. The nonlinear optical polycrystalline transparent ceramic has periodically distributed processed and unprocessed regions along the light transmission direction. The processed and unprocessed regions have different refractive indices, forming a phase grating with a periodically distributed refractive index. The processed regions provide the phase difference between the fundamental frequency light, signal light, and difference frequency light, and these processed regions do not exhibit nonlinear optical effects. This invention enables difference frequency laser output in the infrared band by adding a periodic phase method to the nonlinear optical polycrystalline ceramic to achieve optical frequency conversion.

The application discloses a kind of curved surface transparent protective ceramic composite protective material and its preparation method, comprising: using dry pressing process preforming, then using cold isostatic pressing process compaction preparation curved surface transparent ceramic body, CNC precision machining after high-temperature sintering, surface polishing, obtain curved surface transparent ceramic;With curved surface ceramic opening upwards fixed, cut good at least two layers of plane glass is placed in sequence on the curved surface transparent ceramic, between each layer of glass and ceramic surface spray silicon dioxide, in oven heating softening closely adhered to the surface of the curved surface transparent ceramic;From top to bottom in order according to organic plate, the multilayer plane glass and the curved surface transparent ceramic each layer between film is glued, the glued vacuum rubber ring is covered and is carried out cold air extraction, is transferred to autoclave after pressurizing and heating, exhaust decompression, remove transparent ceramic composite FH material, cut off surrounding excess film and obtain the vehicle curved surface transparent protective ceramic composite protective material.