531 results about "Alumina ceramic" patented technology

The invention discloses a preparation process of an aluminum oxide ceramic material, which comprises the following steps: S1, pretreatment of aluminum oxide powder: taking alpha-Al2O3 powder as a raw material, adding a dispersion medium, carrying out ball milling, transferring into an ultrasonic dispersion machine, dispersing, and further carrying out vacuum drying to obtain pretreated aluminum oxide powder; s2, chemical activation treatment: weighing pretreated aluminum oxide, magnesium oxide, nano silicon dioxide, calcium oxide, zirconium dioxide, titanium dioxide and modified nano silicon carbide in parts by weight, mixing, sequentially adding a dispersing agent absolute ethyl alcohol and a KH550 silane coupling agent, stirring at a high speed, adding a polyvinyl alcohol binder, and continuously stirring to obtain ceramic slurry; s3, sieving the ceramic slurry, filling the ceramic slurry into a mold, and performing isostatic pressing to obtain a ceramic green body; and S4, putting the ceramic green body into a box-type sintering furnace, sintering step by step, and cooling to room temperature along with the furnace to obtain the aluminum oxide ceramic material. The prepared aluminum oxide ceramic material has high compactness, excellent dielectric strength and mechanical property, low energy consumption and great application potential.

The invention provides modified zirconium silicate whisker reinforced aluminum oxide ceramic as well as a preparation method and application thereof, and belongs to the technical field of new materials. The preparation method comprises the following steps: modifying the surface of alumina powder with a silane coupling agent with sulfydryl to generate zirconium silicate in situ, uniformly mixing the zirconium silicate with zirconium silicate whiskers which are treated by hydrogen peroxide and modified by phytic acid and tannic acid and a CeO2-Y2O3-MgO-SiO2 compound, and performing spark plasma sintering to obtain the modified zirconium silicate whisker reinforced alumina ceramic. The modified zirconium silicate whisker reinforced aluminum oxide ceramic prepared by the invention has better interface bonding force, excellent mechanical properties and good wear resistance, realizes ceramic densification, and has wide application prospects.

The application belongs to the field of ceramic fibers, and particularly relates to a preparation method of fine-crystal dense alumina ceramic fibers. The application first configures an aluminum sol, an iron sol, a PVP solution and an acidified silica sol, then mixes them according to a set proportion to obtain a mixed sol, concentrates the mixed sol to obtain a spinnable gel, heats the spinnable gel to 500-600 DEG C at a heating rate of 2-10 DEG C / min for pre-sintering after spinning, finally performs microwave sintering at 1000-1400 DEG C at a power of 3000-5000 W and a heating rate of 50-100 DEG C / min to obtain the fine-crystal dense alumina ceramic fibers. The application has simple and controllable process, and the obtained product has excellent performance and is convenient for large-scale industrial application.

The invention discloses an aluminum oxide ceramic tube shell production device and a preparation method, and belongs to the technical field of aluminum oxide ceramic tube shell preparation, the technical scheme is that the aluminum oxide ceramic tube shell production device comprises a forming mechanism, a transferring mechanism, a sintering mechanism and a surface treatment mechanism, the transferring mechanism is used for transferring the formed aluminum oxide ceramic tube shell to the sintering mechanism, the sintering mechanism is used for sintering the formed aluminum oxide ceramic tube shell, and the surface treatment is used for carrying out surface treatment on the sintered aluminum oxide ceramic tube shell. According to the scheme, the adjacent aluminum oxide ceramic tube shells can be uniformly heated, the product quality is ensured, the uniform heating time of the single aluminum oxide ceramic tube shell can be prolonged, repeated sintering is not needed, and the preparation efficiency is improved.

The invention belongs to the technical field of ceramic materials, and particularly discloses whisker toughened zirconium oxide-aluminum oxide composite ceramic and an additive manufacturing method thereof, the composite ceramic comprises the following components by mass: 94 parts of zirconium oxide toughened aluminum oxide ceramic and 5 parts of silicon carbide whisker; the zirconium oxide toughened aluminum oxide ceramic is prepared from the following components in parts by mass: 76 parts of aluminum oxide and 24 parts of zirconium oxide, and 3mol% of yttrium oxide is added into the zirconium oxide. According to the whisker toughened zirconium oxide-aluminum oxide composite ceramic and the additive manufacturing method thereof, the preparation method has unique design of components and process, and the preparation of a high-density and high-performance ceramic-based composite material part based on a fused deposition modeling technology is successfully realized. Further, the prepared silicon carbide whisker toughened zirconium oxide-aluminum oxide-based composite ceramic has relatively high density and excellent obdurability.

The invention discloses a composite material with a shielding function, a preparation method thereof and an interphone shell. The composite material comprises a polycarbonate-acrylonitrile-butadiene-styrene copolymer, a modified conductive filler, maleic anhydride grafted polyethylene, polyaryletherketone, a flame retardant, an antioxidant, glass microfibers and a compatilizer, wherein the modified conductive filler is aluminum oxide ceramic particles subjected to chemical copper plating and graft polymerization treatment. The preparation method comprises the steps of modified conductive filler preparation, step-by-step raw material mixing, twin-screw extrusion granulation and drying. The interphone shell is prepared from the composite material through injection molding, and the injection molding process comprises the steps of raw material drying, injection molding machine preheating, charging and injection molding, and demolding and finishing. The composite material is stable in electromagnetic shielding performance and has good mechanical strength and heat resistance; the preparation method can improve the dispersity of the components and is adaptive to conventional equipment; the interphone shell can block electromagnetic wave interference, is suitable for being used in multiple environments, and meets the requirements of an electronic equipment shell for shielding and structural performance.

The invention relates to the technical field of ceramic manufacturing processes, and particularly discloses a preparation method of a 96 aluminum oxide ceramic substrate, which comprises the following steps: slurry preparation: carrying out ball milling treatment on high-purity aluminum oxide powder, a sintering aid, a binder, a plasticizer, an organic solvent and a dispersing agent, and fully mixing to obtain tape casting slurry; forming a green body, coating a carrier film with the tape casting slurry through a tape casting machine with a wet film which is uniform in thickness and flat in surface, and drying the carrier film through a drying box in a partitioned manner to obtain a cured green body; and sintering densification treatment: carrying out glue removal treatment on the green body, and carrying out stepped heating sintering to obtain the 96 aluminum oxide ceramic substrate. According to the 96 aluminum oxide ceramic substrate prepared by the scheme, a large number of uniform crystal cores can be formed, small crystal grains can be dissolved, large crystal grains grow at a constant speed, and the uniformity of the crystal grain size is ensured, so that scattering of phonons on a crystal boundary can be reduced, and a structural foundation is laid for improvement of heat conductivity.

The application relates to the technical field of ceramic materials, and provides a SiC-whisker-reinforced alumina ceramic material with whisker directional arrangement and a preparation method thereof. SiC whiskers are magnetically modified by being coated with cobalt, then the magnetically modified SiC whisker powder is mixed with Al2O3 ceramic slurry which has been ball milled, and sodium polystyrene sulfonate is added to the mixture for sufficient mixing in a dispersing machine. Then, an electric field and a magnetic field are simultaneously applied to the mixed solution, so that the SiC whiskers are turned under the action of the electric field and the magnetic field, and directional arrangement of the SiC whiskers in a certain direction is realized. The solution is immediately transferred into a freeze-drying machine to freeze and fix the directional arrangement, and then vacuum sublimation drying is carried out at low temperature, so that the Al2O3-Y2O3-SiC ceramic material with SiC whisker directional arrangement is prepared. w The mixed powder is subjected to hot-pressing sintering to prepare the SiC-whisker-reinforced alumina ceramic material with obvious whisker directional arrangement. The ceramic material can be used for preparing a ceramic cutting tool, and is used for high-efficiency cutting of a nickel-based high-temperature alloy.

The invention discloses a preparation method of high-density aluminum oxide ceramic and the high-density aluminum oxide ceramic, and the preparation method comprises the following steps: adding a silane coupling agent ethanol solution into alpha-Al2O3 powder for modification treatment to obtain modified powder; the modified powder is subjected to doping treatment, doped powder is obtained, and the mass percent of the modified powder in the doped powder is larger than 97.5%; the method comprises the following steps: filling doped powder in a preset range of a key area of a graphite mold, filling pure modified powder on the outer layer of the doped powder, and wrapping carbon felt after pre-pressing and compacting to obtain a pre-pressed sample; the pre-pressed sample is put into a rapid hot-pressing sintering furnace, O2 / Ar mixed atmosphere is introduced, the temperature is gradually increased to a first sintering temperature, and meanwhile, the pressure applied to the mold is gradually increased to the sintering pressure according to the temperature increasing progress; keeping the temperature for a period of time at the first sintering temperature and the sintering pressure; after heat preservation is finished, the sintering pressure is kept, the temperature is reduced to a second sintering temperature, natural cooling is conducted to the room temperature, and the target high-density aluminum oxide ceramic is obtained.

The invention discloses a preparation method of a high-strength aluminum oxide ceramic substrate, which comprises the following steps: firstly, modifying aluminum oxide powder by a liquid phase method, and coating a layer of nano magnesium oxide on the surface of the aluminum oxide powder; then carrying out ball milling treatment on the modified powder, rare earth metal oxide, metal oxide, an organic solvent, a binder, a plasticizer and a dispersing agent together, then carrying out defoaming, tape casting, drying and laminated hot pressing to obtain a ceramic green body, and finally carrying out sintering molding in an air atmosphere to obtain the ceramic. The nano magnesium oxide active coating layer constructed in situ and the added exogenous sintering aid act together, so that uniform growth of isometric crystals is promoted, development of a small amount of dominant oriented grains is directionally induced, a composite enhanced microstructure is formed, atomic scale super-uniform distribution and optimal interface combination of the nano magnesium oxide and the exogenous sintering aid are realized, and the nano magnesium oxide / exogenous sintering aid composite material is prepared. The bending strength of the obtained alumina ceramic can reach up to 881 MPa.

The invention relates to the technical field of preparation of alumina ceramic materials, in particular to an alumina-based porcelain insulator porcelain body and a preparation method thereof. The alumina-based porcelain insulator porcelain body is prepared from interface repair type alumina and a sintering aid, the mass ratio of the interface repair type aluminum oxide to the sintering aid is 100: (5-10); the sintering aid is at least one of zirconium oxide, rare earth oxide, calcium oxide, magnesium oxide, silicon dioxide and manganese dioxide; the interface repair type aluminum oxide is interface metal atom repair type aluminum oxide, the interface metal atom repair type aluminum oxide comprises carrier aluminum oxide and metal atoms anchored at defect points of the carrier aluminum oxide in a monatomic form, and the metal atoms at least comprise Al. The alumina-based porcelain insulator porcelain body has the advantages of small dielectric constant and low dielectric loss, and meets the electrical performance requirements of extra-high voltage power transmission on insulators.

The invention provides porous alumina ceramic and a preparation method thereof, and relates to the technical field of ceramic materials. The invention relates to a preparation method of porous alumina ceramic. The preparation method comprises the following steps: dispersing alpha-cellulose powder in deionized water to form a cellulose suspension; stirring to fully swell the cellulose and form uniform gel, and freeze-drying to obtain a template; dissolving aluminum nitrate hexahydrate, magnesium nitrate hexahydrate and yttrium nitrate hexahydrate in absolute ethyl alcohol to obtain a precursor solution; putting gamma-Al2O3 micro powder and ammonium fluoride into a ball milling tank, adding the precursor solution and a dispersing agent, adding zirconium oxide balls and absolute ethyl alcohol into the ball milling tank, and performing ball milling to obtain ceramic slurry; dipping a template into the ceramic slurry, and performing dipping treatment under a vacuum condition to form a composite green body; and sintering to obtain the porous alumina ceramic. According to the porous aluminum oxide ceramic, the process stability is improved, and the problem that the strength is sharply reduced when the porosity is too high is solved.

The invention relates to the field of advanced ceramic materials, in particular to a ceramic matrix composite (CMC) and a preparation method thereof. The technical problems that a traditional CMC preparation technology is long in period, poor in structural uniformity and insufficient in toughness are solved. According to the method, surface-modified aluminum oxide ceramic microspheres are used as reinforcements, the surfaces of the microspheres are sequentially modified with hexagonal boron nitride nanosheets and a metal nickel catalyst, the microspheres, silicon carbide nanoparticles and a polycarbosilane precursor are mixed to form slurry, and a complex component is formed through multi-material additive manufacturing. A green body is prepared by using a 3D printing technology combining photocuring and material extrusion; carrying out ultraviolet curing on the green body, and carrying out staged heat treatment in an inert atmosphere, so that the precursor polymer is subjected to cross-linking curing, and meanwhile, carbon nanowires grow through in-situ catalysis; and finally, sintering under a pressurizing condition to realize matrix densification. The preparation period is greatly shortened, and the obtained composite material is uniform in structure, compact in matrix and excellent in mechanical property.

The invention relates to the technical field of material sealing, in particular to a high-performance insulating ceramic sealing method for a neutron tube, which comprises the following steps: sequentially carrying out organic solvent ultrasonic cleaning and argon plasma etching activation treatment on a sealing surface of a cylindrical high-purity aluminum oxide ceramic piece, and depositing a titanium transition layer through magnetron sputtering, the ceramic piece with the titanium transition layer is obtained; the sealing face of the kovar alloy cylindrical flange plate is subjected to acid pickling, an oxide layer is removed, cleaning and drying are conducted, and a metal sealing part is obtained; preparing an active brazing filler metal sheet; the components are assembled in sequence to form a pre-assembled component; the pre-assembled component is placed in a vacuum brazing furnace, axial pre-tightening force is applied to the pre-assembled component, sealing is completed, then cooling is controlled, and a sealing piece with an airtight brazing joint is formed; and carrying out annealing treatment to obtain a finished product sealing assembly. Therefore, the problems of low dielectric strength, large thermal expansion coefficient difference, difficulty in interface quality control and the like in the prior art are solved.

The invention discloses a one-dimensional heat flux density measuring device based on the Fourier law, and relates to the technical field of object heat flux density measurement. Comprising a heating unit, a sealing heat insulation unit, a cooling unit, a temperature acquisition unit and a data processing unit. The sealing heat insulation unit comprises a heat insulation material, an aluminum oxide ceramic tube, a sealing air layer, an outer layer supporting plate and a rubber or silica gel sealing ring. The heating unit comprises a high-temperature copper plate heating platform; the cooling unit comprises a water cooling head, a cooling water jacket and a cooling water tank, and is nested at the top of the sealed heat insulation unit; according to the temperature acquisition unit, a thermocouple is attached to the surface of a measured object and is connected with an external thermodetector; the data processing unit comprises an acquisition terminal and a computer, the acquisition terminal is connected with a USB interface of the computer and a USB interface of the thermodetector, and data acquired by the thermodetector is transmitted to the computer. The invention provides the heat flux density measuring device which is simple and convenient to assemble, low in construction cost and simple and convenient to calculate, and the measuring efficiency is improved.

The invention relates to the technical field of structural ceramics, and discloses an aluminum oxide ceramic, the aluminum oxide ceramic comprises a doping element, the doping element comprises at least one of magnesium, calcium, yttrium, lanthanum, zirconium and cerium, and the doping amount of the doping element is 600ppm-1000ppm. According to the aluminum oxide ceramic provided by the invention, through uniform doping of trace doping elements in aluminum oxide, modification of a grain boundary structure, grain morphology and size of the aluminum oxide ceramic is realized, so that the aluminum oxide ceramic provided by the invention is high-purity aluminum oxide ceramic with excellent mechanical strength, electrical properties and thermal conductivity.

The invention discloses a high-temperature-resistant passive strain gauge for gas turbine blade monitoring and a preparation method and application thereof, and belongs to the technical field of gas turbine health monitoring. The high-temperature-resistant passive strain gauge comprises a strain gauge substrate, an insulating layer, a snakelike sensitive grid, a fiber bragg grating (FBG) and a yttria-stabilized zirconia (YSZ) protective layer. The strain gauge has the beneficial effects that aiming at the limitation of a traditional sensor in a high-temperature (greater than or equal to 1200 DEG C), high-frequency vibration and corrosion environment, the strain gauge adopts the high-temperature-resistant platinum-tungsten alloy snakelike sensitive grid, the single crystal aluminum oxide ceramic substrate and the sapphire fiber bragg grating to transmit a strain signal through wavelength shift, and an external power supply is not needed; and the Ir-Re alloy is brazed and fixed to the microgroove in the surface of the blade, the shearing strength is high, and the service life is long. The method overcomes the technical bottleneck of strain measurement in a high-temperature environment, is suitable for scenes of aero-engines, gas turbine blades and the like, and remarkably reduces the maintenance cost and improves the monitoring reliability.

The invention provides an aluminum oxide ceramic-based wave-absorbing material and a preparation method thereof, and belongs to the field of ceramic-based composite materials. The method comprises the following steps: mixing a resin monomer, a light curing agent, aluminum oxide powder, a dispersing agent, a rheological additive and a sintering additive to obtain aluminum oxide ceramic slurry; according to preset ceramic structure model data, the aluminum oxide ceramic slurry is subjected to photocuring 3D printing, and an aluminum oxide ceramic biscuit is obtained; degreasing and sintering the alumina ceramic biscuit to obtain an alumina ceramic matrix; and loading the wave-absorbing agent on an aluminum oxide ceramic matrix to obtain the aluminum oxide ceramic-based wave-absorbing material. The alumina ceramic-based wave-absorbing material has the characteristics of complex and adjustable structure, light weight, high precision, high mechanical strength, high melting point, broadband absorption and the like. The working temperature of a part made of the composite material can reach 900 DEG C or above, and the composite material can resist severe environments such as high-speed airflow scouring, oxidation and gas corrosion and can be used as a light-weight bearing part to be applied to invisible equipment.

The invention discloses a preparation method of a zirconium oxide toughened aluminum oxide ceramic substrate, which comprises the following steps: respectively carrying out surface modification on aluminum oxide powder and zirconium oxide powder by adopting a coupling agent, a catalyst and a cross-linking agent, then mixing the two modified powder with a rare earth sintering aid, a dispersing agent, a binder and a plasticizer, and carrying out ball milling treatment, thereby obtaining the zirconium oxide toughened aluminum oxide ceramic substrate. Carrying out tape casting and sintering processes to obtain a target ceramic substrate; the preparation method is simple, the process is easy to control, the bending strength of the prepared zirconium oxide toughened aluminum oxide ceramic substrate can reach 847 MPa at most, and the fracture toughness can reach 7.6 MPa.m < 1 / 2 > at most.

The invention relates to a brazing method for an aluminum oxide ceramic / niobium metal high-temperature-resistant structural member, which is characterized by comprising the following steps of: 1, plating nickel on a tungsten metallization layer of aluminum oxide ceramic; and secondly, vacuum brazing is conducted on the aluminum oxide ceramic and niobium metal through the AuNi 17.5 / tungsten net / AuNi 17.5 composite brazing filler metal. According to the method, a layer of nickel metal is electroplated on the tungsten metallization layer, spreading of the brazing filler metal is facilitated, the tungsten metallization density can be increased, and the wettability of the brazing filler metal on an interface can be improved. And by adopting the gold-nickel brazing filler metal, the welding seam forming quality and the temperature resistance of the joint can be improved.

The invention relates to the field of light-emitting devices, and discloses an LED light-emitting device and a manufacturing method thereof, and the LED light-emitting device comprises a composite substrate which comprises an aluminum oxide ceramic substrate and an aluminum nitride ceramic block body; the aluminum oxide ceramic substrate is provided with a hollow area, and the aluminum nitride ceramic block is located in the hollow area; the LED chip is fixed on the upper surface of the aluminum nitride ceramic block body; the box dam is fixed on the upper surface of the composite substrate, the inner surface, facing the LED chip, of the box dam is an inclined surface, and the inclined surface inclines towards the center far away from the composite substrate; all the LED chips are located in the range of the box dam; a first reflective layer on the inclined surface; and the packaging colloid is used for packaging the LED chip. By designing the composite substrate and the box dam with the inner surface being the inclined surface, the lighting effect and the light spot quality of the LED light-emitting device can be improved, and meanwhile the edge yellowing phenomenon is eliminated.

The invention provides an MAX phase / alumina layered composite ceramic and an in-situ synthesis preparation method thereof, and the method comprises the following steps: respectively preparing an alumina matrix layer and an MAX phase interface layer through a tape casting method, then alternately laminating the alumina matrix layer and the MAX phase interface layer, and finally carrying out hot pressed sintering to obtain a layered composite ceramic product. According to the invention, the layered composite ceramic which takes aluminum oxide as a matrix and MAX-phase ceramic as an interlayer is prepared through an in-situ synthesis technology, so that the effects of great toughening, strength increase without reduction and high damage tolerance are realized, and the fracture mode is converted from brittle fracture of aluminum oxide ceramic to safe stepped fracture. The strength and toughness of the aluminum oxide ceramic are successfully balanced and synergistically improved, and the industrial problem that strength and toughness cannot be both considered in a traditional aluminum oxide ceramic toughening technology is solved.

The invention discloses aluminum oxide foamed ceramic for casting and filtering molten aluminum and a preparation method of the aluminum oxide foamed ceramic, and belongs to the technical field of aluminum oxide ceramics. The method comprises the following steps: firstly, carrying out plasma activation on polyurethane foam, then immersing the polyurethane foam into a composite modifier system consisting of a main modifier, an auxiliary modifier and a catalyst, and sequentially carrying out first-stage grafting and second-stage cross-linking reaction to introduce carboxyl-hydroxyl composite functional groups and a heterocyclic cross-linking structure to the surface of the foam, so as to obtain a modified precursor; uniformly coating the precursor with aluminum oxide ceramic slurry by adopting a vacuum-pressure alternate impregnation method, and finally drying and sintering at high temperature to obtain a finished product. By constructing a strong interface bonding layer, the adhesion uniformity and firmness of ceramic slurry on an organic precursor are remarkably improved, the aluminum oxide foamed ceramic which is compact in framework, few in defect, high in mechanical strength, excellent in filtering performance and resistant to molten aluminum erosion is obtained, and the aluminum oxide foamed ceramic is suitable for molten liquid purification of high-end aluminum castings.

The invention belongs to the technical field of ceramic material preparation, and particularly relates to a high-wear-resistance high-strength large-specification aluminum oxide ceramic ball preparation method which comprises the steps of main raw material treatment, spray granulation, servo press preforming, automatic bagging and vacuumizing, ultrahigh-pressure cold isostatic pressing, high-temperature sintering, comprehensive performance detection and the like. The high-performance ceramic ball with the diameter of 20-100mm, the compressive strength of more than 250MPa and the apparent porosity of less than 0.1% is prepared through the processes of multi-stage refining and homogenizing, sectional spray granulation, secondary densification, temperature programming sintering and the like. The wear resistance, the strength and the microstructure uniformity of the large-specification aluminum oxide ceramic ball can be remarkably improved, and the high-end industrial application requirement can be met.

The invention relates to black aluminum oxide ceramic with adjustable resistivity and a preparation method thereof. The preparation method of the black aluminum oxide ceramic with the adjustable resistivity comprises the following steps: (1) mixing MnO2 powder, Fe2O3 powder, NiO powder, CoO powder and Cr2O3 powder, and calcining to obtain a black pigment; and (2) mixing Al2O3 powder with the black pigment and the resistivity regulator to obtain black aluminum oxide raw material powder, and then carrying out molding, glue discharging and sintering to obtain the black aluminum oxide ceramic with the adjustable resistivity.

The application discloses an ultrahigh-temperature radar material level meter probe, which comprises a top end part, a radar probe and a signal transmission part, one end of the radar probe is connected with the top end part, and the other end is connected with the signal transmission part; the signal transmission part comprises a radar tube, one end of the radar tube is connected with the radar probe, and the other end is connected with a fixing flange, the signal transmission part is fixed to an external structure through the fixing flange; a protective cover is in a conical structure, is fixed to one end of the radar tube away from the radar probe, and is in contact with the outside; the protective cover is made of alumina ceramic, the content of alumina is not less than 99%, the thickness of the protective cover is 3mm-15mm, and the angle is 100 degrees-150 degrees. The application solves the problem that the existing radar material level meter probe is difficult to effectively monitor the material level in a high-temperature environment due to the limitation of the radar material level meter probe itself.

The utility model provides a ball-milling device for aluminum oxide ceramic processing, which relates to the field of ball-milling devices and comprises a support, a ball-milling mechanism arranged on the support, a feeding frame arranged above the ball-milling mechanism, a crushing frame arranged on the feeding frame in a sliding manner, a crushing device arranged in the crushing frame and a ball-milling mechanism arranged above the ball-milling mechanism, a flow guide frame is arranged at the position, located above the crushing device, of the crushing frame, the flow guide frame vibrates through vibration devices on the two sides of the crushing frame, and a driving device is further installed on the support and can drive the crushing frame to reciprocate. According to the ball milling device for aluminum oxide ceramic machining, the rotating wheel and the inserting rod are driven to rotate through the second motor, so that the movable frame drives the crushing frame to reciprocate, materials are poured into the flow guide frame and fall between the two crushing rollers under the action of the flow guide frame, and due to the reciprocating motion of the crushing rollers, the materials can be crushed more uniformly. And therefore, the materials fall onto the two crushing rollers more uniformly.

The preparation method comprises the following steps: dispersing CeO2 nanoparticles in absolute ethyl alcohol containing diluted hydrochloric acid, activating, adding a certain amount of a silane coupling agent and diluted hydrochloric acid, carrying out a water bath reaction for a certain time, separating after the reaction is finished to obtain a surface-modified CeO2 nanoparticle crude product, and purifying to obtain the organic silicon separation membrane. The CeO2 nanoparticles with the modified surfaces are obtained; dissolving an organic silicon precursor 1, 2-bis (triethoxysilyl) ethylene in absolute ethyl alcohol, adding deionized water and diluted hydrochloric acid, heating and stirring to form a Si-OH intermediate, stirring and adding the surface modified CeO2 to obtain CeO2 modified organic silicon sol; coating a porous aluminum oxide ceramic tube with the CeO2 modified organic silicon sol, and calcining to obtain a CeO2 modified separation membrane; compared with an organic silicon separation membrane modified by noble metal, the separation membrane prepared by the method is relatively low in cost, good in stability in a complex gas environment and relatively good in hydrogen selectivity.

This invention discloses a method for combining CNC high-precision high-temperature resistant insulating substrate engraving with tin-copper alloy printed circuit 3D printing, belonging to the field of high-power circuit carrier manufacturing technology. The invention uses 99.7% alumina ceramic or silicon nitride ceramic as the insulating substrate, achieving high-precision structural forming of ±0.005-0.025mm through CNC layer engraving. Sandblasting, roughening, sensitization, activation, and pre-plating surface modification enhance interfacial adhesion. CuSn10 tin bronze is used as the printing material, and the circuit is formed by SLM or FDM 3D printing at a sintering temperature of 850-900℃, achieving a forming density ≥98.71%. Through stepped heating sintering and high-temperature resistant inorganic adhesive curing, the ceramic substrate and tin-copper alloy circuit are integrated. The circuit carrier obtained by this invention has a long-term temperature resistance of ≥1600℃, a volume resistivity of ≥10¹⁴Ω·cm, a current carrying capacity of 15.6A for 3mm lines, and an adhesion strength retention rate of ≥95% after 1000 thermal cycles. The temperature rise is 15~20℃ lower than that of traditional PCBs. It is suitable for high-load, high-current scenarios such as industrial power supplies and new energy power control. It is compatible with processes and has complete industrial support, and has significant technical and economic feasibility.

The present application relates to a kind of transition layer powder, transition layer and its preparation method and application, the preparation raw material of the transition layer powder is composed of tungsten, manganese oxide, silicon dioxide and aluminium oxide;With mass percentage, the mass percentage of tungsten in the preparation raw material of the transition layer powder is 75wt% or more;The mass ratio of tungsten and manganese oxide is 8:1 to 20:1 The preparation raw material of the transition layer powder provided by the present application uses tungsten, manganese oxide, silicon dioxide and aluminium oxide, and controls the ratio of tungsten and manganese oxide, so that it can form the transition layer with the tungsten skeleton structure of small pore when being applied on high-purity alumina ceramic substrate, it is convenient for copper-based brazing filler metal to melt into the tungsten skeleton pore of transition layer and form tungsten copper infiltration effect, and has the effect of wetting tungsten material, so as to improve the connection strength between high-purity alumina ceramic substrate with purity of 99wt% or more and tungsten material.