A zirconium diboride-based ultrahigh-temperature ceramic material and a preparation method and device thereof

Abstract

The application discloses a zirconium diboride-based ultrahigh-temperature ceramic material and a preparation method and a preparation device thereof, and comprises the following steps: S1, preparing a zirconium diboride ceramic blank; S2, placing the zirconium diboride ceramic blank into a heating element to perform sintering by electrifying, the blank is wrapped by the heating element, the heating element is made of conductive material, and the sintering condition is that a direct-current power supply outputs constant power, the output power is 1300-2300 W, the holding time is 10-90 s, and then the power supply is disconnected to naturally cool. The heating element can be rapidly heated by high-power electrification, a high-temperature temperature field is formed between the upper and lower surfaces of the heating element, heat is conducted into the blank through heat radiation, the blank is sintered, and thus densification is completed, a very fast heating rate is realized, the dense ultrahigh-temperature ceramic is prepared in a short sintering period, the traditional sintering mode that is high in energy consumption and long in time consumption is broken, and large-batch production can be performed in a very short period.

Description

Technical Field

[0001] This invention belongs to the field of ultra-high temperature ceramics, and relates to a zirconium diboride-based ultra-high temperature ceramic material and its preparation method and apparatus. Background Technology

[0002] Hypersonic vehicles, when flying within the atmosphere, experience surface temperatures reaching 1800℃ due to aerodynamic heating. This "thermal barrier" problem has become a major challenge restricting the development and application of hypersonic vehicles, requiring components with excellent thermal protection capabilities. Ultra-high temperature ceramics are materials that maintain good performance under high temperature and high pressure environments, primarily comprising diborides, carbides, and other high-melting-point compounds of transition metals. Among these, boride ultra-high temperature ceramics mainly include transition metal boride ceramics such as zirconium diboride, hafnium diboride, tantalum diboride, and niobium diboride, possessing characteristics such as high melting point, high hardness, low density, good mechanical properties, and high-temperature stability. Zirconium diboride, with its extremely high melting point (>2800℃) and relatively low density, is currently the most promising ultra-high temperature thermal protection material.

[0003] However, existing methods for preparing zirconium diboride ultra-high temperature ceramics mainly include hot pressing sintering, spark plasma sintering, reactive hot pressing sintering, pressureless sintering, and lightning sintering. Most of these methods require very high sintering temperatures (≥1800℃) and long holding times (≥1h), resulting in extremely high energy consumption. Furthermore, prolonged high-temperature operation poses significant safety hazards to the equipment. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide a zirconium diboride-based ultra-high temperature ceramic material, its preparation method and preparation device, which can rapidly raise the temperature to the sintering temperature. It has the characteristics of simple equipment, convenient operation and extremely short sintering cycle, and can realize the large-scale rapid preparation of ultra-high temperature ceramics.

[0005] To achieve the above objectives, the present invention employs the following technical solution:

[0006] A method for preparing zirconium diboride-based ultra-high temperature ceramic materials includes the following steps:

[0007] S1, preparing zirconium diboride ceramic blanks;

[0008] S2, a zirconium diboride ceramic blank is placed in a heating element and sintered by applying electricity. The heating element is made of conductive material and encloses the blank. The sintering conditions are: constant power output of DC power supply, output power of 1300-2300W, holding time of 10-90s, and then the power supply is disconnected and the blank is cooled naturally to obtain zirconium diboride-based ultra-high temperature ceramic material.

[0009] Preferably, the process for preparing the zirconium diboride ceramic preform is as follows:

[0010] S11, Zirconium diboride powder and sintering aid powder are mixed at a sintering aid volume ratio of 5 to 30 vol% to obtain the initial powder;

[0011] S12, the initial powder is subjected to wet ball milling at a speed of 240-580 r / min for 6-12 h.

[0012] S13, dry the slurry after wet ball milling at a temperature of 50-80℃ for about 2-4 hours;

[0013] S14, the dried powder is cold isostatically pressed into shape, with a pressure of 15-25KN and a holding time of 3-10min; to obtain a zirconium diboride ceramic blank.

[0014] Furthermore, the initial particle size of the zirconium diboride powder is 0.5–10 μm, and the initial particle size of the sintering aid powder is 1–10 μm.

[0015] Furthermore, the sintering aid is boron carbide, molybdenum disilicide, or silicon carbide.

[0016] Furthermore, the dried powder is ground and sieved through a sieve with a mesh size of 80 to 150.

[0017] Preferably, the heating element is made of carbon fiber felt, carbon paper or graphite plate.

[0018] Preferably, when powered on, the heating element is wrapped with an alumina fiber ceramic insulation block.

[0019] A zirconium diboride-based ultra-high temperature ceramic material prepared by the aforementioned method.

[0020] A device for preparing zirconium diboride-based ultra-high temperature ceramic materials includes a sintering platform and a glove box, wherein the sintering platform is placed inside the glove box;

[0021] The sintering platform includes a base plate and two clamping ends; the clamping ends include an upper clamping end, a lower clamping end, an electrical connection end, and an insulating base;

[0022] The power receiving end is a vertical flat plate with sliding grooves on both sides of the upper half. The upper clamping end has an L-shaped structure with a through groove in the vertical section and protrusions on both sides of the through groove that mate with the sliding groove. The lower clamping end has an inverted L-shaped structure with through holes in both the vertical section and the lower half of the power receiving end. The lower clamping end is connected to the power receiving end by bolts passing through the two through holes. After the upper and lower clamping ends are connected to the power receiving end, the horizontal sections of the upper and lower clamping ends face the same side. The top of the insulating base has a square hole, and the bottom of the vertical section of the lower clamping end and the bottom of the power receiving end are inserted into the square hole for fixation. The base plate has two clamping ends, with the upper and lower clamping ends facing each other. The power receiving end is connected to a DC power supply via a wire.

[0023] Preferably, the top of the base plate is provided with guide rails running through both sides, the bottom of the insulating base is provided with guide blocks, the insulating base is inserted into the base plate, and the guide blocks slide together.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] The heating element of this invention can rapidly heat up upon high-power energization, creating a high-temperature field between its upper and lower surfaces. Heat is then conducted to the zirconium diboride ceramic blank via thermal radiation, causing sintering and densification. This achieves an extremely rapid heating rate (~500℃ / s), producing dense ultra-high temperature ceramics within a short sintering cycle (<1 min). This breaks away from the traditional energy-intensive and time-consuming sintering methods for ultra-high temperature ceramics, enabling mass production in a very short period. Simultaneously, the extremely rapid heating rate and short sintering cycle are beneficial for producing ultra-high temperature ceramics with fine grains, which improves their mechanical properties. This invention eliminates the need for molds during ceramic sintering, and the blank shape is not limited by molds. It can prepare ultra-high temperature ceramics with complex structures and high density, and is particularly suitable for preparing complex structures of ZrB2-based ultra-high temperature ceramics. Attached Figure Description

[0026] Figure 1 This is a flowchart illustrating the preparation process of the zirconium diboride-based ultra-high temperature ceramic material of the present invention.

[0027] Figure 2 The diagram shows the microstructure and composition of the zirconium diboride-based ultra-high temperature ceramic material in Example 1 of this invention.

[0028] Figure 3 The diagram shows the microstructure and composition of the zirconium diboride-based ultra-high temperature ceramic material in Example 2 of this invention.

[0029] Figure 4 A schematic diagram of the heating element of the present invention supported by a zirconium diboride ceramic blank;

[0030] Figure 5 This is a schematic diagram of the apparatus for preparing zirconium diboride-based ultra-high temperature ceramic materials according to the present invention.

[0031] Figure 6 This is a schematic diagram of the sintering platform structure of the present invention;

[0032] Figure 7 This is a side view of the sintering platform of the present invention;

[0033] Figure 8 This is a front view of the upper clamping end of the present invention;

[0034] Figure 9 This is a side view of the upper clamping end of the present invention;

[0035] Figure 10 This is a top view of the upper clamping end of the present invention;

[0036] Figure 11 This is a perspective view of the upper clamping end of the present invention;

[0037] Figure 12 This is a front view of the power connection terminal of the present invention;

[0038] Figure 13 This is a side view of the power connection terminal of the present invention;

[0039] Figure 14 This is a top view of the power connection terminal of the present invention;

[0040] Figure 15 This is a perspective view of the power connection terminal of the present invention;

[0041] Figure 16 This is a front view of the lower clamping end of the present invention;

[0042] Figure 17 This is a side view of the lower clamping end of the present invention;

[0043] Figure 18 This is a top view of the lower clamping end of the present invention;

[0044] Figure 19 This is a perspective view of the lower clamping end of the present invention;

[0045] Figure 20 This is a front view of the insulating base of the present invention;

[0046] Figure 21 This is a side view of the insulating base of the present invention;

[0047] Figure 22 This is a top view of the insulating base of the present invention;

[0048] Figure 23 This is a perspective view of the insulating base of the present invention;

[0049] Figure 24 This is a front view of the base plate of the present invention;

[0050] Figure 25 This is a side view of the base plate of the present invention;

[0051] Figure 26 This is a top view of the base plate of the present invention;

[0052] Figure 27 This is a perspective view of the base plate of the present invention.

[0053] Wherein: 1-zirconium diboride ceramic blank; 2-heating element; 3-alumina fiber ceramic insulation block; 4-upper clamping end; 5-lower clamping end; 6-electrical connection end; 7-insulating base; 8-base plate. Detailed Implementation

[0054] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0055] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of the stated features. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0056] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terms “installation,” “connection,” and “linkage” should be interpreted broadly, for example, as a fixed connection, a detachable connection, or an integral connection; a mechanical connection, an electrical connection, or a connection that allows communication; a direct connection or an indirect connection via an intermediate medium; or a connection within two elements or an interaction between two elements. The term “and / or” as used herein includes any and all combinations of one or more of the associated listed items. Those skilled in the art will understand the specific meaning of the above terms in this invention according to the specific circumstances. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention.

[0057] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0058] The following disclosure provides many different embodiments or examples for implementing various structures of the invention. To simplify the disclosure, specific examples of components and arrangements are described below. These are merely examples and are not intended to limit the invention. Furthermore, reference numerals and / or letters may be repeated in different examples; such repetition is for simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or arrangements discussed. In addition, examples of various specific processes and materials are provided in this invention, but those skilled in the art will recognize the application of other processes and / or the use of other materials.

[0059] like Figure 1 As shown, the zirconium diboride-based ultra-high temperature ceramic material of the present invention has a chemical composition of ZrB2–xvol% sintering aid.

[0060] The specific steps for the ultra-rapid preparation of the zirconium diboride-based ultra-high temperature ceramic material are as follows:

[0061] 1) After weighing zirconium diboride powder and sintering aid powder according to the designed volume ratio, ultrasonically mix them to obtain the initial powder, which is then poured into a ball mill jar. Both the ball mill jar and the grinding balls are made of zirconium oxide, and anhydrous ethanol is added as the grinding medium. The mass ratio of zirconium oxide grinding balls to initial powder is 3-6:1, and the mass ratio of anhydrous ethanol to initial powder is 3.5-7:10.

[0062] The zirconium diboride powder particles are spherical, square, or irregular in shape.

[0063] The initial particle size of the zirconium diboride powder is 0.5–10 μm.

[0064] The sintering aid is boron carbide, molybdenum disilicide, or silicon carbide, etc.

[0065] The initial diameter of the sintering aid powder is 1–10 μm.

[0066] The volume ratio of the sintering aid is 5-30 vol%.

[0067] 2) The ball mill jar containing the initial powder and anhydrous ethanol medium is fixed on a planetary ball mill for wet ball milling. The ball milling speed is 240-580 r / min and the ball milling time is 6-12 h.

[0068] 3) Pour the wet ball-milled powder slurry into a petri dish. Add an appropriate amount of anhydrous ethanol to the ball mill jar again, shake, and pour it back into the petri dish. Repeat this operation three times. Place the petri dish containing the slurry in a constant temperature oven to dry at 50–80°C for approximately 2–4 hours. Then grind the powder and sieve it through a sieve with a mesh size of 80–150.

[0069] 4) The obtained powder is introduced into a stainless steel mold for cold isostatic pressing. The diameter of the stainless steel mold is 6-10 mm, the applied pressure is 15-25 KN, and the holding time is 3-10 min. After pressing, a zirconium diboride ceramic blank 1 is obtained.

[0070] 5) such as Figure 4 As shown, a zirconium diboride ceramic blank 1 is placed in a heating element 2, which encloses the blank. The blank has a diameter of 6-10 mm and a thickness of 1-2 mm. The heating element 2 has dimensions of length × width × height = 90-100 mm × 20-30 mm × 3-5 mm.

[0071] Heating element 2 is made of conductive materials, specifically conductive devices such as carbon fiber felt, carbon paper, and graphite plate.

[0072] 6) The heating element 2 containing the zirconium diboride ceramic blank 1 is clamped on the designed preparation device and sintered by power supply. The heating element 2 is wrapped with an alumina fiber ceramic insulation block 3. The sintering conditions are: constant power output of DC power supply, output power of 1300-2300W, holding time of 10-90s, and then disconnecting the power supply for natural cooling.

[0073] In this invention, heating elements 2, such as carbon fiber felt, carbon paper, and graphite plates, can be rapidly heated by high-power electricity, forming a high-temperature field between the upper and lower surfaces of the heating elements 2. Heat is then conducted into the green body through thermal radiation, causing sintering and densification. This achieves an extremely rapid heating rate (~500℃ / s), producing dense ultra-high temperature ceramics within a short sintering cycle (<1 min). This breaks away from the traditional sintering mode of ultra-high temperature ceramics, which is energy-intensive and time-consuming, enabling mass production in a very short period. Simultaneously, the extremely rapid heating rate and short sintering cycle are beneficial for producing ultra-high temperature ceramics with fine grains, which improves the mechanical properties of the ceramics. This invention eliminates the need for molds during ceramic sintering, and the shape of the green body is not limited by molds. It can prepare ultra-high temperature ceramics with complex structures and high density, and is particularly suitable for preparing complex structures of ZrB2-based ultra-high temperature ceramics.

[0074] Example 1

[0075] The preparation steps of zirconium diboride-based ultra-high temperature ceramic materials are as follows:

[0076] Preparation of S1, zirconium diboride-based ultra-high temperature ceramic preforms

[0077] Spherical zirconium diboride powder with an initial particle size of 0.5 μm and boron carbide sintering aid powder with an initial particle size of 1 μm were weighed at a sintering aid volume ratio of 15 vol% and poured into a zirconium oxide ball mill jar for ultrasonic mixing. Zirconia grinding beads and anhydrous ethanol were added to the ball mill jar, with a mass ratio of zirconium oxide grinding beads to mixed powder of 5:1 and anhydrous ethanol to mixed powder of 3.5:10. The ball mill jar containing the initial powder and anhydrous ethanol was fixed on a planetary ball mill for wet ball milling at 240 rpm for 12 hours. The wet-milled powder slurry was poured into a petri dish. An appropriate amount of anhydrous ethanol was added again to the ball mill jar, shaken, and poured back into the petri dish; this operation was repeated three times. The petri dish containing the slurry was placed in a constant temperature oven to dry at 50°C for 4 hours. The powder was then ground and sieved through a 120-mesh sieve. An appropriate amount (~0.2g) of the obtained powder is introduced into a stainless steel mold for cold isostatic pressing. The stainless steel mold has a diameter of 10mm, the applied pressure is 20KN, and the holding time is 5min to obtain a zirconium diboride-based ultra-high temperature ceramic green body.

[0078] Preparation of S2, zirconium diboride-based ultra-high temperature ceramic materials

[0079] The pressed preform is placed in a carbon fiber felt. The carbon fiber felt containing the preform is then clamped in the designed preparation apparatus for sintering. The sintering conditions are: constant power output from a DC power supply of 1500W for 30 seconds, followed by disconnection and natural cooling. This process yields a dense zirconium diboride-based ultra-high temperature ceramic material, the microstructure and composition of which are as follows. Figure 2 As shown.

[0080] Example 2

[0081] The preparation steps of zirconium diboride-based ultra-high temperature ceramic materials are as follows:

[0082] Preparation of S1, zirconium diboride-based ultra-high temperature ceramic preforms

[0083] Spherical zirconium diboride powder with an initial particle size of 0.5 μm and molybdenum disilicide sintering aid powder with an initial particle size of 1 μm were weighed at a sintering aid volume ratio of 20 vol% and poured into a zirconium oxide ball mill jar for ultrasonic mixing. Zirconia grinding beads and anhydrous ethanol were added to the ball mill jar, with a mass ratio of zirconium oxide grinding beads to mixed powder of 5:1 and anhydrous ethanol to mixed powder of 3.5:10. The ball mill jar containing the initial powder and anhydrous ethanol was fixed on a planetary ball mill for wet ball milling at 240 rpm for 12 hours. The wet-milled powder slurry was poured into a petri dish. An appropriate amount of anhydrous ethanol was added again to the ball mill jar, shaken, and poured back into the petri dish; this operation was repeated three times. The petri dish containing the slurry was placed in a constant temperature oven to dry at 50°C for approximately 4 hours. The powder was then ground and sieved through a 100-mesh sieve. An appropriate amount (~0.3g) of the obtained powder is introduced into a stainless steel mold for cold isostatic pressing. The stainless steel mold has a diameter of 10mm, the applied pressure is 25KN, and the holding time is 3min to obtain a zirconium diboride-based ultra-high temperature ceramic green body.

[0084] Preparation of S2, zirconium diboride-based ultra-high temperature ceramic materials

[0085] The pressed preform is placed in a carbon fiber felt. The carbon fiber felt containing the preform is then clamped in the designed preparation apparatus for sintering. The sintering conditions are: constant power output from a DC power supply of 1550W for 30 seconds, followed by disconnection and natural cooling. This process yields a dense zirconium diboride-based ultra-high temperature ceramic material, the microstructure and composition of which are as follows. Figure 3 As shown.

[0086] Example 3

[0087] The preparation steps of zirconium diboride-based ultra-high temperature ceramic materials are as follows:

[0088] Preparation of S1, zirconium diboride-based ultra-high temperature ceramic preforms

[0089] Spherical zirconium diboride powder with an initial particle size of 1 μm and silicon carbide sintering aid powder with an initial particle size of 10 μm were weighed at a sintering aid volume ratio of 30 vol% and poured into a zirconium oxide ball mill jar for ultrasonic mixing. Zirconia grinding beads and anhydrous ethanol were added to the ball mill jar, with a mass ratio of zirconium oxide grinding beads to mixed powder of 6:1 and anhydrous ethanol to mixed powder of 5:10. The ball mill jar containing the initial powder and anhydrous ethanol was fixed on a planetary ball mill for wet ball milling at a speed of 580 r / min for 10 h. The wet-milled powder slurry was poured into a petri dish. An appropriate amount of anhydrous ethanol was added again to the ball mill jar, shaken, and then poured back into the petri dish; this operation was repeated three times. The petri dish containing the slurry was placed in a constant temperature oven to dry at 60℃ for 3 h. The powder was then ground and sieved through an 80-mesh sieve. The obtained powder (~0.2g) is introduced into a stainless steel mold for cold isostatic pressing. The stainless steel mold has a diameter of 10mm, the applied pressure is 15KN, and the holding time is 5min to obtain a zirconium diboride-based ultra-high temperature ceramic green body.

[0090] Preparation of S2, zirconium diboride-based ultra-high temperature ceramic materials

[0091] The pressed blank is placed in a carbon fiber felt. The carbon fiber felt containing the blank is then clamped in the designed preparation device for sintering. The sintering conditions are: constant power output of DC power supply, output power of 1300W, holding time of 90s, and then disconnecting the power supply and allowing it to cool naturally to obtain a dense zirconium diboride-based ultra-high temperature ceramic material.

[0092] Example 4

[0093] The preparation steps of zirconium diboride-based ultra-high temperature ceramic materials are as follows:

[0094] Preparation of S1, zirconium diboride-based ultra-high temperature ceramic preforms

[0095] Spherical zirconium diboride powder with an initial particle size of 0.8 μm and boron carbide sintering aid powder with an initial particle size of 5 μm were weighed at a sintering aid volume ratio of 5 vol% and poured into a zirconium oxide ball mill jar for ultrasonic mixing. Zirconia grinding beads and anhydrous ethanol were added to the ball mill jar, with a mass ratio of zirconium oxide grinding beads to mixed powder of 3:1 and anhydrous ethanol to mixed powder of 7:10. The ball mill jar containing the initial powder and anhydrous ethanol was fixed on a planetary ball mill for wet ball milling at a speed of 400 rpm for 6 hours. The wet-milled powder slurry was poured into a petri dish. An appropriate amount of anhydrous ethanol was added again to the ball mill jar, shaken, and poured back into the petri dish; this operation was repeated three times. The petri dish containing the slurry was placed in a constant temperature oven to dry at 80℃ for 2 hours. The powder was then ground and sieved through a 150-mesh sieve. The obtained powder (~0.2g) is introduced into a stainless steel mold for cold isostatic pressing. The stainless steel mold has a diameter of 10mm, the applied pressure is 15KN, and the holding time is 5min to obtain a zirconium diboride-based ultra-high temperature ceramic green body.

[0096] Preparation of S2, zirconium diboride-based ultra-high temperature ceramic materials

[0097] The pressed blank is placed in a carbon fiber felt. The carbon fiber felt containing the blank is then clamped in the designed preparation device for sintering. The sintering conditions are: constant power output of DC power at 2300W, holding time of 100s, followed by disconnection of the power supply and natural cooling to obtain a dense zirconium diboride-based ultra-high temperature ceramic material.

[0098] In another embodiment, the present invention provides an apparatus for preparing the zirconium diboride-based ultra-high temperature ceramic material, such as... Figure 5 As shown, the fabrication assembly includes a programmable DC power supply, wires, a sintering platform, and a glove box.

[0099] The sintering platform is placed inside a glove box and connected to a DC power supply via wires. The glove box is filled with an inert gas environment, specifically argon. The wires are connected to the power terminals of the sintering platform, and the heating element 2 is fixed inside the sintering platform via upper and lower clamping ends. The billet is placed within the heating element 2.

[0100] The programmable DC power supply has a constant current output / constant power output mode and can be connected to a computer to control the power supply output current / power through programming.

[0101] like Figure 6 and Figure 7 As shown, the sintering platform includes a base plate 8 and two clamping ends.

[0102] The clamping end includes an upper clamping end 4, a lower clamping end 5, a power connection end 6, and an insulating base 7.

[0103] like Figures 12-15 As shown, the power connection terminal 6 is connected to a DC power supply via a wire. The power connection terminal 6 is a vertical flat plate, and the upper half of the power connection terminal 6 has sliding grooves on both sides.

[0104] like Figures 9-11 As shown, the upper clamping end 4 has an L-shaped structure. The vertical section of the upper clamping end 4 is provided with a through groove. The inner walls on both sides of the through groove are provided with protrusions that cooperate with the sliding groove. After the through groove of the upper clamping end 4 is inserted into the upper half of the power connection end 6, the protrusions and the sliding groove cooperate to form a sliding connection.

[0105] like Figures 16-19 As shown, the lower clamping end 5 has an inverted L-shaped structure. Both the vertical section of the lower clamping end 5 and the lower half of the power connection end 6 are provided with through holes. The lower clamping end 5 is connected to the power connection end 6 by bolts passing through the two through holes.

[0106] After the upper clamping end 4 and the lower clamping end 5 are connected to the power connection end 6, the horizontal sections of the upper clamping end 4 and the lower clamping end 5 face the same side.

[0107] The bottom of the horizontal section 4 at the upper clamping end and the top of the horizontal section 5 at the lower clamping end are both provided with concave and convex stripes to increase the clamping friction.

[0108] like Figures 20-23 As shown, the top of the insulating base 7 is provided with a square hole, and the bottom of the vertical section of the lower clamping end 5 and the bottom of the power connection end 6 are inserted into the square hole to be fixed.

[0109] like Figures 6-7 As shown, the base plate 8 is provided with two clamping ends, with the upper clamping end 4 and the lower clamping end 5 arranged opposite to each other.

[0110] like Figures 24-27 As shown, the top of the base plate 8 is provided with guide rails that run through both sides, and the bottom of the insulating base 7 is provided with guide blocks. The insulating base 7 is inserted into the base plate 8, and the guide blocks slide together.

[0111] The upper clamping end 4 of the sintering platform is connected to the power receiving end 6 via a sliding groove, and the lower clamping end 5 is connected to the power receiving end 6 via bolts. After the upper clamping end 4 and the lower clamping end 5 are connected to the power receiving end 6, the sintering platform is placed on the insulating base 7. The insulating base 7 and the base plate 8 form a guide rail-guide block structure, and the distance between the left and right ends can be adjusted to accommodate heating elements 2 of different sizes. The programmable DC power supply output mode is constant current output / constant power output, which can be linked to a computer to control the power output current / power through programming, thereby changing the sintering temperature by changing the current / power.

[0112] The upper clamping end 4, lower clamping end 5, and power connection end 6 of the sintering platform are all made of No. 45 steel, the insulating base 7 is made of alumina ceramic, and the base plate 8 is made of aluminum alloy.

[0113] The specific steps for preparing zirconium diboride-based ultra-high temperature ceramic materials using the aforementioned preparation apparatus are as follows:

[0114] The pressed zirconium diboride-based ultra-high temperature ceramic blank is placed into heating element 2. Heating element 2, containing the blank, is clamped in the clamping end of the sintering platform, and then sintering is performed. The power output is set via computer programming (selecting the power output mode: constant current output / constant power output, setting the output power / power-time curve), and after the power supply executes the operation, it is disconnected and allowed to cool naturally to obtain dense zirconium diboride-based ultra-high temperature ceramic material. A schematic diagram of the preparation apparatus is shown below. Figure 5 As shown, the carbon fiber felt containing the zirconium diboride ceramic preform 1 is as follows Figure 4 As shown, the sintering platform is as follows Figure 6 As shown.

[0115] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0116] It should be understood that the above description is for illustrative purposes and not for limitation. Many embodiments and applications beyond the provided examples will be apparent to those skilled in the art upon reading the above description. Therefore, the scope of this teaching should not be determined by reference to the above description, but rather by reference to the foregoing claims and the full scope of their equivalents. For purposes of completeness, all articles and references, including patent applications and publications, are incorporated herein by reference. The omission of any aspect of the subject matter disclosed herein in the foregoing claims is not intended as a waiver of that subject matter, nor should it be construed as an indication that the applicant has not considered that subject matter as part of the disclosed inventive subject matter.

Claims

1. A device for preparing zirconium diboride-based ultra-high temperature ceramic materials, characterized in that, Includes a sintering platform and a glove box, with the sintering platform placed inside the glove box; The sintering platform includes a base plate (8) and two clamping ends; the clamping ends include an upper clamping end (4), a lower clamping end (5), an electrical connection end (6), and an insulating base (7); The power receiving end (6) is a vertical flat plate. Slide grooves are provided on both sides of the upper half of the power receiving end (6). The upper clamping end (4) has an L-shaped structure. A through groove is provided on the vertical section of the upper clamping end (4). Protrusions that mate with the slide groove are provided on the inner walls of both sides of the through groove. The lower clamping end (5) has an inverted L-shaped structure. Through holes are provided on both the vertical section of the lower clamping end (5) and the lower half of the power receiving end (6). The lower clamping end (5) is connected to the power receiving end (6) by bolts passing through the two through holes. The upper clamping end ( 4) After the lower clamping end (5) is connected to the power receiving end (6), the horizontal section of the upper clamping end (4) and the horizontal section of the lower clamping end (5) face the same side; the top of the insulating base (7) is provided with a square hole, and the bottom of the vertical section of the lower clamping end (5) and the bottom of the power receiving end (6) are inserted into the square hole to be fixed; two clamping ends are provided on the base plate (8), and the upper clamping end (4) and the lower clamping end (5) of the two clamping ends are arranged opposite to each other; the power receiving end (6) is connected to the DC power supply through a wire; The zirconium diboride-based ultra-high temperature ceramic material is prepared by a method comprising the following steps: S1, prepare zirconium diboride ceramic blank (1). S2, the zirconium diboride ceramic blank (1) is placed in the heating element (2) and sintered by power supply. The heating element (2) wraps the blank and is made of conductive material. The sintering conditions are: constant power output of DC power supply, output power of 1300~2300 W, holding time of 10~90s, and then the power supply is disconnected and the blank is cooled naturally to obtain zirconium diboride-based ultra-high temperature ceramic material.

2. The apparatus for preparing zirconium diboride-based ultra-high temperature ceramic materials according to claim 1, characterized in that, The heating element (2) is made of carbon fiber felt, carbon paper or graphite plate.

3. The apparatus for preparing zirconium diboride-based ultra-high temperature ceramic materials according to claim 1, characterized in that, When powered on, the heating element (2) is wrapped with an alumina fiber ceramic insulation block (3).

4. The apparatus for preparing zirconium diboride-based ultra-high temperature ceramic materials according to claim 1, characterized in that, The bottom plate (8) is provided with guide rails running through both sides, and the bottom of the insulating base (7) is provided with guide blocks. The insulating base (7) is inserted into the bottom plate (8), and the guide blocks slide together.

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