Ceramming apparatus for metal oxides and method for ceramming alumina fibers

Abstract

The application discloses a metal oxide ceramicizing device and an alumina fiber ceramicizing method, and particularly relates to the technical field of oxide ceramicizing. The metal oxide ceramicizing device comprises a workbench, a cover body is fixedly arranged at the top end of the workbench, a plurality of laser heating parts, the output power of the plurality of laser heating parts is sequentially increased in steps, and the output power of the laser heating part at the last stage is kept constant, and each laser heating part is used for emitting a uniform and continuous rectangular heating spot to the top end of the workbench. The application directly heats the extremely fine alumina fiber by using the laser, so that the energy waste in the traditional volume heating mode is avoided. The stepwise power control of the plurality of laser heating parts is combined with the uniform heating of the rectangular spot, so that rapid and uniform heating is realized. Meanwhile, the closed-loop temperature control and the partition atmosphere protection effectively prevent the cracks of the fiber caused by thermal stress or the incomplete crystal type conversion.

Description

Technical Field

[0001] This invention relates to the field of oxide ceramization technology, specifically to an apparatus for ceramizing metal oxides and a method for ceramizing alumina fibers. Background Technology

[0002] Alumina fiber is a polycrystalline inorganic fiber whose main component is alumina. Its main crystal form can be γ-, δ-, θ-, or α-alumina. It typically also contains about 5% silicon dioxide to stabilize the crystal phase and inhibit grain growth at high temperatures. Alumina fiber is one of the newest ultra-lightweight high-temperature insulation materials available both domestically and internationally. It is produced using a high-tech sol-gel method, where soluble aluminum and silicon salts are made into a colloidal solution with a certain viscosity. The solution is then centrifuged at high speed to form fiber preforms, which are then transformed into Al-Si alumina polycrystalline fibers through dehydration, drying, and medium-to-high temperature heat treatment.

[0003] In existing ceramic processing, nascent alumina fibers are typically heated in box furnaces or pit furnaces, usually with 3-5 constant temperature zones, and some processes even have dozens of zones, each requiring insulation. This heating method is volumetric heating, with a large amount of energy used to heat the furnace air, refractory bricks, and kiln furniture, while the energy actually absorbed by the extremely fine alumina fibers with a diameter of only 10-20 μm is less than 5% of the total energy consumption. Due to reliance on air convection and thermal radiation for heat transfer, the inner and outer layers of the nascent fibers are heated unevenly, requiring extremely low heating rates to prevent fiber breakage. This results in production lines that are tens of meters long, with low production efficiency and large equipment footprint.

[0004] To address the aforementioned energy waste, one might consider using laser beams to heat nascent fibers. Laser heating offers advantages such as concentrated energy, a small heat-affected zone, and high energy efficiency, avoiding significant energy waste. However, the ceramization process of alumina nascent fibers typically requires a relatively enclosed environment because the processing demands specific atmospheric conditions, which laser emitting devices struggle to withstand. Furthermore, the rapid, instantaneous heating of lasers can generate substantial thermal stress within the nascent fibers, potentially leading to crack formation or incomplete crystal transformation. Therefore, achieving efficient and uniform ceramization of alumina nascent fibers while ensuring stable laser operation has become a pressing technical challenge. Summary of the Invention

[0005] The purpose of this invention is to provide an apparatus for ceramicizing metal oxides and a method for ceramicizing alumina fibers, so as to overcome the above-mentioned shortcomings in the prior art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a ceramicization apparatus for metal oxides, comprising: The workbench has a cover fixedly installed on its top. Multiple laser heating elements are evenly arranged at the top of the cover. Along the conveying direction of the fiber to be processed, the output power of the multiple laser heating elements increases in a stepwise manner, and the output power of the laser heating element in the last stage remains constant. Each laser heating element is used to emit a uniform and continuous rectangular heating spot towards the top of the worktable to perform stepwise heating and heat preservation on the nascent metal oxide fiber. Multiple protective components are respectively disposed at the laser emitting ends of the multiple laser heating parts. The protective components allow the laser to pass through and be directed toward the top of the worktable, while isolating the high-temperature environment inside the cover from the laser heating parts.

[0007] Preferably, the laser heating unit includes a laser emitter and an infrared temperature sensor. The laser emitter is fixedly mounted on the top of the cover, and the infrared temperature sensor is correspondingly mounted on the rectangular heating spot emitted by the laser emitter. The temperature data detected by the infrared temperature sensor is transmitted to the laser emitter in real time, and the laser emitter adjusts its output power in real time according to the temperature data. The laser emitter and the infrared temperature sensor communicate with each other through a controller for data reception and control.

[0008] Preferably, the top of the cover has multiple windows, the emitting ends of multiple laser emitters extend into the corresponding windows, and multiple protective components are fixedly installed in the corresponding windows.

[0009] Preferably, the protective element is made of fused silica material.

[0010] Preferably, two partitions are fixedly installed inside the cover, which divide the interior of the cover into a preheating zone, a sintering zone, and a heat preservation zone; the output power of the plurality of laser heating parts located at the top of the heat preservation zone remains constant.

[0011] Preferably, each of the protective components is provided with a vent at its bottom end, the vent being used to blow gas out from the bottom of the protective component to form an air curtain; The ventilation section includes two opposite and staggered hollow air blowing plates, a hollow rod and a first tube; the two hollow air blowing plates spray airflow from two directions to form an air curtain, the hollow rod connects the interior of the two hollow air blowing plates, one end of the first tube connects to the interior of the hollow rod, and the other end is used to connect to an external air blowing device. The airflow blown out by the ventilation section located at the top of the preheating zone is oxygen, which is used to form an air curtain and maintain the oxygen environment inside the preheating zone; the airflow blown out by the ventilation section located at the top of the sintering zone and the heat preservation zone is inert gas, which is used to form an air curtain and maintain the inert gas environment inside the sintering zone and the heat preservation zone.

[0012] Preferably, an arc-shaped plate is fixedly provided at the angle between the inner top and the two side walls of the cover, and the arc surface of the arc-shaped plate faces the air outlet direction of the hollow air blowing plate, so as to change the airflow direction ejected by the hollow air blowing plate.

[0013] Preferably, the workbench is provided with a conveying section for conveying nascent metal oxide fibers sequentially through the preheating zone, the sintering zone, and the heat preservation zone; The conveying unit includes a conveyor belt and a ceramic fiber paper layer disposed at the outer end of the conveyor belt. The conveyor belt is made of high-temperature resistant ceramic fiber material. Multiple folds are formed on the ceramic fiber paper layer. The flat portion between two adjacent folds is used to place metal oxide nascent fibers, and the width of the flat portion is the same as the width of the rectangular heating spot emitted by a single laser heating unit. Each of the folding components has a placement groove inside, and multiple three-way tubes are provided in the placement groove. The three-way tubes are used to support the folding component, and two ends of the three-way tubes pass through the two side walls of the folding component respectively. The conveyor belt has multiple through holes, and the through holes are connected to the third end of the corresponding three-way tubes, so that the water vapor and organic matter generated by heating are discharged sequentially through the three-way tubes and the through holes.

[0014] Preferably, the top of the workbench is provided with three frames, which are respectively located inside the preheating zone, the sintering zone, and the heat preservation zone; the opening of the frame is attached to the inner end face of the conveyor belt and communicates with multiple through holes; each frame is fixedly provided with a second pipe communicating with its interior, the second pipe being used to connect to an external air extraction device to extract the air inside the frame, so that the water vapor and organic matter generated by heating can quickly enter the interior of the frame through the three-way pipe and the through holes; Multiple columns are rotatably connected to the inner wall of the cover via bearings. The columns are located at the outer edge of the conveyor belt and are used to press the conveyor belt against the top opening of the frame.

[0015] This invention also discloses a method for ceramicizing alumina fibers, comprising the following steps: Step S1: The alumina nascent fibers prepared by the sol-gel process are aligned and guided; Step S2: Spread the arranged nascent fibers evenly onto the flat area of ​​the ceramic fiber paper layer; Step S3: During the operation of the conveyor belt and the ceramic fiber paper layer, multiple laser heating units located above the conveyor belt and the ceramic fiber paper layer are used to irradiate and heat the nascent fibers below, causing the nascent fibers to undergo a gradual phase change and complete the ceramicization process.

[0016] The technical effects and advantages provided by the present invention in the above technical solution are as follows: This invention employs laser direct heating of extremely fine alumina fibers, avoiding the energy waste caused by heating furnace air, refractory bricks, and kiln furniture in traditional volumetric heating methods. Through stepped power control of multiple laser heating sections, combined with uniform heating by rectangular laser spots, rapid and uniform temperature rise is achieved, avoiding the excessively long production lines caused by slow heating rates in traditional processes. Simultaneously, closed-loop temperature control and zoned atmosphere protection effectively prevent fiber cracking due to thermal stress or incomplete crystal transformation, thus improving product yield and mechanical properties.

[0017] By setting up fused silica protective components to isolate the laser from the high-temperature furnace environment, and combining this with the air curtain formed by the ventilation section, the laser can be allowed to pass through normally while preventing damage to the laser from high temperature and volatiles. This allows laser heating technology to be stably applied to closed ceramicization processes.

[0018] Oxygen is introduced into the preheating zone to promote the rapid decomposition of organic matter, while inert gas is introduced into the sintering and insulation zones to prevent oxidation. Combined with the three-way pipe, through holes, and exhaust frame, exhaust gas is discharged in a directional and rapid manner, avoiding surface contamination and internal pore defects in the fiber, thus ensuring the purity and density of the fiber. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For those skilled in the art, other drawings can be obtained based on these drawings.

[0020] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a schematic cross-sectional view of the overall structure of the present invention; Figure 3 This is a schematic diagram of the overall front view of the present invention; Figure 4 This is a schematic cross-sectional view of the cover structure of the present invention; Figure 5 This is a schematic diagram of the internal structure of the cover of the present invention; Figure 6 This is a three-dimensional structural diagram of the ventilation section of the present invention; Figure 7 This is a partial structural diagram of the conveying section of the present invention; Figure 8 This is a schematic diagram of the three-dimensional structure of the frame and the second tube of the present invention.

[0021] Explanation of reference numerals in the attached figures: 100. Workbench; 110. Cover; 111. Window; 112. Column; 120. Partition; 130. Preheating zone; 140. Sintering zone; 150. Insulation zone; 200. Laser heating unit; 300. Protective components; 400. Ventilation section; 410. Hollow air blowing plate; 420. Hollow rod; 430. First tube body; 500, curved plate; 600. Conveying section; 610. Conveyor belt; 611. Through hole; 620. Ceramic fiber paper layer; 621. Folding part; 622. Placement groove; 623. T-shaped pipe body; 700. Frame; 710. Second tube body. Detailed Implementation

[0022] To enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0023] In existing alumina fiber ceramicization processes, nascent fibers are typically placed in box furnaces or pit furnaces for zoned volumetric heating. A significant amount of energy is used to heat the furnace air, refractory bricks, and kiln furniture, with less than 5% of the total energy actually absorbed by the extremely fine fibers, which have a diameter of only 10-20 μm. Furthermore, relying on air convection and thermal radiation for heat transfer results in uneven heating between the inner and outer layers, necessitating extremely low heating rates. This leads to production lines that are tens of meters long, resulting in low production efficiency and large floor space requirements. To reduce energy consumption, laser heating might be considered. While laser heating offers advantages such as concentrated energy and high efficiency, laser emitting devices struggle to withstand the high-temperature, enclosed environment required for ceramicization, and instantaneous heating can easily generate thermal stress, leading to fiber cracking or incomplete crystal transformation.

[0024] To address the aforementioned problems, this invention provides an apparatus for the ceramization of metal oxides. For example... Figures 1 to 4 As shown, the device includes: a worktable 100, a cover 110, multiple laser heating elements 200, and multiple protective components 300.

[0025] A cover 110 is fixedly installed at the top of the worktable 100, forming a closed processing environment. Multiple laser heating elements 200 are evenly arranged at the top of the cover 110. Along the fiber conveying direction, the output power of the multiple laser heating elements 200 increases sequentially in a stepwise manner and remains constant in the final stage. Each laser heating element 200 emits a uniform and continuous rectangular heating spot towards the top of the worktable 100, performing stepwise heating and heat preservation on the nascent oxide fibers. Multiple protective components 300 are respectively installed at the laser emitting ends of the laser heating elements 200, allowing the laser to pass through while isolating the high-temperature environment inside the cover 110 from the laser heating elements 200. Through the above structure, this invention utilizes laser to directly heat the fiber, avoiding the energy waste of volumetric heating; through stepwise power control and uniform heating with rectangular spots, it solves the problems of thermal stress cracking and insufficient crystal transformation; and through the protective components, it achieves isolation between the laser and the high-temperature environment, enabling laser heating to be stably applied to closed ceramicization processes.

[0026] like Figures 2 to 4 As shown, in a specific embodiment: two partitions 120 are fixedly installed inside the cover 110, which divide the interior of the cover 110 into a preheating zone 130, a sintering zone 140, and a heat preservation zone 150 arranged sequentially along the fiber conveying direction. Multiple windows 111 are provided at the top of the cover 110, and the positions of the windows 111 correspond to the respective heating zones.

[0027] like Figure 2 and Figure 3 As shown, multiple laser heating elements 200 are uniformly arranged at the top of the cover 110. Each laser heating element 200 includes a laser emitter and an infrared temperature sensor. The emitting end of the laser emitter extends into the corresponding window 111. Along the conveying direction of the fiber to be processed (i.e., from the preheating zone to the heat preservation zone), the output power of the multiple laser heating elements 200 increases sequentially in a stepwise manner, while the output power of the laser heating element 200 located at the top of the heat preservation zone 150 remains constant. Each laser heating element 200 is used to emit a uniform and continuous rectangular heating spot towards the top of the worktable 100. The rectangular heating spot is formed by recutting and combining a circular Gaussian spot through diffractive optical elements or a microlens array to perform stepwise heating and heat preservation of the nascent metal oxide fiber. The infrared temperature sensor is correspondingly arranged at the rectangular heating spot emitted by the laser emitter to detect the temperature data of the fiber surface in real time and transmit the temperature data to the laser emitter in real time. The laser emitter adjusts its output power in real time based on the received temperature data. The laser emitter and the infrared temperature sensor communicate via a controller to receive and control data, thereby achieving closed-loop temperature control.

[0028] like Figure 4As shown, multiple protective components 300 are respectively fixedly installed in multiple windows 111, located below the emitting end of the laser emitter. The protective components 300 are made of fused silica material, which allows the laser to pass through and be directed to the top of the worktable 100, while isolating the high-temperature environment inside the cover 110 from the laser heating part 200 to prevent high temperature damage to the laser.

[0029] To enable the laser heating unit 200 to more stably and efficiently heat the nascent metal oxide fibers uniformly, the present invention has found the following areas for improvement in addressing the aforementioned problems: First, different heating stages require different atmospheric environments. The preheating zone requires oxygen to promote the full oxidation and decomposition of organic matter, while the sintering and heat preservation zones require inert gases (such as argon or nitrogen) to prevent high-temperature oxidation of the fibers. A single atmosphere cannot meet the requirements of the entire process. Second, the laser window (i.e., the protective component 300) is exposed to high-temperature volatiles for extended periods, and water vapor and organic matter easily adhere to and deposit on its surface, leading to a gradual decrease in light transmittance and affecting the stability and uniformity of laser heating.

[0030] To achieve precise control of the zoned atmosphere along the delivery direction, and to simultaneously form a gas barrier below the laser window to effectively prevent volatile substances from contaminating the window and ensure long-term stable laser transmission. Figures 4 to 6 As shown, a vent 400 is provided at the bottom of each protective component 300. The vent 400 includes two opposing and staggered hollow air-blowing plates 410, a hollow rod 420, and a first tube 430. The two hollow air-blowing plates 410 eject airflow from two directions to form a cross-air curtain. The hollow rod 420 connects the interiors of the two hollow air-blowing plates 410. One end of the first tube 430 connects to the interior of the hollow rod 420, and the other end is used to connect to an external air-blowing device. The airflow blown from the vent 400 located at the top of the preheating zone 130 is oxygen, used to form an air curtain and maintain an oxygen environment inside the preheating zone 130 to promote the full oxidation and decomposition of organic matter. The airflow blown from the vent 400 located at the top of the sintering zone 140 and the heat preservation zone 150 is an inert gas (such as argon or nitrogen), used to form an air curtain and maintain an inert gas environment inside the sintering zone 140 and the heat preservation zone 150 to prevent high-temperature oxidation. Through this single component, the present invention simultaneously achieves precise control of the zoned atmosphere and protection against contamination by the protective component 300; the cross air curtain forms a gas barrier below the laser window, which not only prevents high-temperature volatiles from contaminating the window, but also achieves precise control of the zoned atmosphere.

[0031] Meanwhile, an arc-shaped plate 500 is fixedly installed at the angle between the top of the inner part of the cover 110 and the two side walls. The arc surface of the arc plate 500 faces the air outlet direction of the hollow air blowing plate 410, which is used to change the airflow direction of the hollow air blowing plate 410, so that the airflow is more evenly distributed in each heating zone and avoids local turbulence from affecting the heating uniformity.

[0032] Based on the aforementioned improvements, this invention further discovers that even if the window contamination problem is alleviated, the large amount of water vapor and organic decomposition products released by the nascent fibers during heating remains a significant challenge. If these gases cannot be expelled from around the fibers in a timely manner, they will remain inside the fibers, forming pores, or cause contamination on the fiber surface, severely affecting the mechanical properties and quality of the ceramicized fibers. Furthermore, the fibers are prone to lateral displacement during transport, resulting in the laser spot not completely covering the fibers, causing uneven heating and insufficient phase transformation in some areas.

[0033] To achieve rapid and directional removal of water vapor and organic matter generated during heating, avoiding contamination of the fiber's internal pores and surface; and simultaneously ensuring that the nascent fibers are precisely positioned at the center of the rectangular heating spot, achieving stable and uniform heating. For example... Figure 7 and Figure 8 As shown, a conveying section 600 is provided on the workbench 100 for conveying nascent metal oxide fibers sequentially through the preheating zone 130, the sintering zone 140, and the heat preservation zone 150. The conveying section 600 includes a conveyor belt 610 and a ceramic fiber paper layer 620 disposed at the outer end of the conveyor belt 610. The conveyor belt 610 is made of high-temperature resistant ceramic fiber material. Multiple folds 621 are formed on the ceramic fiber paper layer 620. The flat portion between two adjacent folds 621 is used to place the nascent metal oxide fibers, and the width of the flat portion is the same as the width of the rectangular heating spot emitted by a single laser heating section 200, ensuring that the spot completely covers the fiber. Each fold 621 has a placement groove 622 inside, and multiple three-way tubes 623 are provided in the placement groove 622. The three-way tubes 623 are used to support the fold 621, and one end of each three-way tube 623 passes through the two side walls of the fold 621. The conveyor belt 610 has multiple through holes 611, which are connected to the third end of the corresponding three-way pipe 623. During the heating process, water vapor and volatile organic compounds generated enter through both ends of the three-way pipe 623 and are discharged through the third end and the through holes 611.

[0034] The top of the workbench 100 is equipped with three frames 700, which are located inside the preheating zone 130, sintering zone 140, and heat preservation zone 150, respectively. The openings of the frames 700 are abutted against the inner end face of the conveyor belt 610 and communicate with multiple through holes 611. Each frame 700 is fixedly equipped with a second pipe 710 communicating with its interior. The second pipe 710 is used to connect to an external air extraction device to extract the air inside the frame 700, allowing the water vapor and organic matter generated by heating to quickly enter the interior of the frame 700 through the three-way pipe 623 and the through holes 611, thus preventing volatile substances from contaminating the fiber surface. Multiple columns 112 are rotatably connected to the inner wall of the cover 110 via bearings. The columns 112 are located at the outer edge of the conveyor belt 610 and are used to press the conveyor belt 610 against the top opening of the frame 700 to ensure sealing. This directional waste discharge structure enables forced and rapid emission of waste gas, effectively avoiding internal pores and surface contamination of the fibers.

[0035] The present invention also discloses a method for ceramicizing alumina fibers using the above-described apparatus, comprising the following steps: Step S1: The alumina nascent fibers prepared by the sol-gel process are arranged and guided. Specifically, the fiber preforms formed by high-speed centrifugation of the sol containing aluminum and silicon salts are arranged neatly to ensure that the fibers do not entangle or overlap, and are arranged in parallel according to the set spacing.

[0036] Step S2: The arranged nascent fibers are laid flat on the flat area of ​​the ceramic fiber paper layer 620. The width of the flat area between two adjacent folds 621 is the same as the width of the rectangular heating spot emitted by a single laser heating unit 200. The fibers are evenly spread within this flat area. The folds 621 serve to separate and position the fibers, preventing them from shifting.

[0037] Step S3: Start the conveyor belt 610 and the ceramic fiber paper layer 620, allowing the nascent fibers to pass sequentially through the preheating zone 130, sintering zone 140, and heat preservation zone 150 at a set linear speed. Simultaneously, start all laser heating units 200, irradiating and heating the nascent fibers below according to a preset stepped power curve. In the preheating zone 130, the laser heating section 200 outputs power of 200~500W to slowly heat the fibers to 400~600℃, causing residual moisture and some organic matter in the fibers to evaporate. At the same time, the ventilation section 400 at the top of the preheating zone blows out oxygen, forming an air curtain and maintaining an oxygen environment to promote the full oxidation and decomposition of organic matter; the exhaust device discharges the exhaust gas in a timely manner through the frame 700. In sintering zone 140, the laser power is gradually increased from 500 to 1500 W, raising the fiber temperature to 800 to 1300°C, causing a crystal transformation. An inert gas (such as argon) is blown out from the ventilation section 400 at the top of the sintering zone, forming a protective gas curtain to prevent high-temperature oxidation of the fiber. In the insulation zone 150, the laser power is maintained at 1500~2000W (adjusted according to the specific fiber diameter) to stabilize the fiber temperature at 1300~1500℃. This temperature is maintained for 10~30 minutes to complete the full crystallization and densification of α-Al2O3. The ventilation section 400 at the top of the insulation zone continues to blow out inert gas to maintain the protective atmosphere.

[0038] Throughout the heating process, an infrared temperature sensor monitors the fiber surface temperature in real time and feeds it back to the controller. The controller adjusts the output power of the laser emitter in real time based on the deviation between the measured temperature and the set curve, achieving closed-loop precise temperature control. At the same time, the three-way tube 623 and the through hole 611, together with the negative pressure suction of the frame 700, quickly discharge the water vapor, organic decomposition products, and waste gas generated during heating, avoiding the formation of pores or surface contamination inside the fiber.

[0039] After the above steps, the nascent alumina fibers undergo ceramicization and are transformed into polycrystalline alumina fibers.

[0040] The foregoing has only described certain exemplary embodiments of the present invention by way of illustration. Undoubtedly, those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the foregoing drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A device for ceramicizing metal oxides, characterized in that, include: A workbench (100) has a cover (110) fixedly installed on its top. Multiple laser heating elements (200) are uniformly arranged at the top of the cover (110). Along the conveying direction of the fiber to be processed, the output power of the multiple laser heating elements (200) increases in a stepwise manner, and the output power of the laser heating element (200) in the last stage remains constant. Each laser heating element (200) is used to emit a uniform and continuous rectangular heating spot to the top of the worktable (100) to perform stepwise heating and heat preservation on the metal oxide nascent fiber. Multiple protective components (300) are respectively disposed on the laser emitting ends of the multiple laser heating parts (200). The protective components (300) allow the laser to pass through and be directed toward the top of the worktable (100), while isolating the high-temperature environment inside the cover (110) from the laser heating parts (200).

2. The ceramicization apparatus for metal oxides according to claim 1, characterized in that: The laser heating unit (200) includes a laser emitter and an infrared temperature sensor. The laser emitter is fixedly installed on the top of the cover (110), and the infrared temperature sensor is correspondingly installed at the rectangular heating spot emitted by the laser emitter. The temperature data detected by the infrared temperature sensor is transmitted to the laser emitter in real time. The laser emitter adjusts its output power in real time according to the temperature data. The laser emitter and the infrared temperature sensor receive and control data through a controller.

3. The ceramicization apparatus for metal oxides according to claim 2, characterized in that: The top of the cover (110) has multiple windows (111), the emitting ends of multiple laser emitters extend into the corresponding windows (111), and multiple protective components (300) are fixedly installed in the corresponding windows (111).

4. The ceramicization apparatus for metal oxides according to claim 1, characterized in that: The protective component (300) is made of fused silica material.

5. The ceramicization apparatus for metal oxides according to claim 1, characterized in that: The cover (110) is fixedly provided with two partitions (120), which divide the interior of the cover (110) into a preheating zone (130), a sintering zone (140) and a heat preservation zone (150); the output power of the plurality of laser heating parts (200) located at the top of the heat preservation zone (150) remains constant.

6. The ceramicization apparatus for metal oxides according to claim 5, characterized in that: Each of the protective components (300) is provided with a vent (400) at its bottom end, the vent (400) being used to blow gas out from the bottom of the protective component (300) to form an air curtain; The ventilation section (400) includes two opposite and staggered hollow air blowing plates (410), a hollow rod (420), and a first tube (430); the two hollow air blowing plates (410) spray airflow from two directions to form an air curtain, the hollow rod (420) connects the interior of the two hollow air blowing plates (410), one end of the first tube (430) connects to the interior of the hollow rod (420), and the other end is used to connect to an external air blowing device; The airflow blown out by the ventilation section (400) located at the top of the preheating zone (130) is oxygen, which is used to form an air curtain and maintain the oxygen environment inside the preheating zone (130); the airflow blown out by the ventilation section (400) located at the top of the sintering zone (140) and the heat preservation zone (150) is inert gas, which is used to form an air curtain and maintain the inert gas environment inside the sintering zone (140) and the heat preservation zone (150).

7. The ceramicization apparatus for metal oxides according to claim 6, characterized in that: An arc-shaped plate (500) is fixedly installed at the angle between the inner top of the cover (110) and the two side walls. The arc surface of the arc plate (500) faces the air outlet direction of the hollow air blowing plate (410) to change the airflow direction ejected by the hollow air blowing plate (410).

8. The ceramicization apparatus for metal oxides according to claim 1, characterized in that: The workbench (100) is provided with a conveying section (600) for conveying the metal oxide nascent fibers through the preheating zone (130), the sintering zone (140) and the heat preservation zone (150) in sequence. The conveying unit (600) includes a conveyor belt (610) and a ceramic fiber paper layer (620) disposed at the outer end of the conveyor belt (610). The conveyor belt (610) is made of high-temperature resistant ceramic fiber material. A plurality of folds (621) are formed on the ceramic fiber paper layer (620). The flat portion between two adjacent folds (621) is used to place metal oxide nascent fibers, and the width of the flat portion is the same as the width of the rectangular heating spot emitted by a single laser heating unit (200). Each of the folding components (621) has a placement groove (622) inside, and a plurality of three-way tubes (623) are provided in the placement groove (622). The three-way tubes (623) are used to support the folding component (621), and two ends of the three-way tubes (623) pass through the two side walls of the folding component (621) respectively. The conveyor belt (610) has a plurality of through holes (611), and the through holes (611) are connected to the third end of the corresponding three-way tubes (623), so that the water vapor and organic matter generated by heating are discharged sequentially through the three-way tubes (623) and the through holes (611).

9. The ceramicization apparatus for metal oxides according to claim 8, characterized in that: The top of the workbench (100) is provided with three frames (700), which are located inside the preheating zone (130), the sintering zone (140) and the heat preservation zone (150), respectively. The opening of the frame (700) is attached to the inner end face of the conveyor belt (610) and communicates with multiple through holes (611). Each frame (700) is fixedly provided with a second pipe (710) communicating with its interior. The second pipe (710) is used to connect to an external air extraction device to extract the air inside the frame (700) so that the water vapor and organic matter generated by heating can quickly enter the interior of the frame (700) through the three-way pipe (623) and the through holes (611). Multiple columns (112) are rotatably connected to the inner wall of the cover (110) via bearings. The columns (112) are located at the outer edge of the conveyor belt (610) and are used to press the conveyor belt (610) against the top opening of the frame (700).

10. A method for ceramicizing alumina fibers using a ceramicizing apparatus for metal oxides according to any one of claims 1-9, characterized in that, Includes the following steps: Step S1: The alumina nascent fibers prepared by the sol-gel process are aligned and guided; Step S2: Spread the arranged nascent fibers evenly onto the flat area of ​​the ceramic fiber paper layer (620); Step S3: During the operation of the conveyor belt (610) and the ceramic fiber paper layer (620), multiple laser heating units (200) located above the conveyor belt (610) and the ceramic fiber paper layer (620) are used to irradiate and heat the nascent fibers below, causing the nascent fibers to undergo a gradual phase change and complete the ceramicization process.

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