Beta silicon carbide synthesis process
Through pulsed laser-induced plasma technology and precise raw material pretreatment and ball mill mixing process, the problems of high energy consumption and poor product quality in traditional β-silicon carbide synthesis methods are solved, and efficient and high-speed β-silicon carbide synthesis is achieved, which meets the high-performance requirements in the high-end field and reduces environmental pollution.
Patent Information
- Application Number
- CN202510159052.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-13
- Publication Date
- 2025-06-06
AI Technical Summary
The traditional β-silicon carbide synthesis method has problems such as high energy consumption, long production cycle, and difficult to control product purity and particle size distribution, which limits its large-scale application and industrial development.
Pulse laser induced plasma technology is used to ensure uniform mixing of silicon powder and carbon powder at the molecular level by precisely controlling the raw material pretreatment and high-energy ball milling mixing process, and plasma reaction is carried out using high-purity argon in the closed reaction chamber.
It greatly accelerates the reaction process, shortens the synthesis time, improves the purity and crystallinity of the product, solves the problems of low synthesis efficiency and poor product quality in traditional methods, meets the high-performance requirements of β-silicon carbide materials in high-end fields, and reduces environmental pollution.
Smart Images
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Abstract
Description
Technical Field
[0001] The invention relates to the technical field of silicon carbide synthesis technology, in particular to a beta silicon carbide synthesis technology. Background Art
[0002] Silicon carbide (SiC), as a wide bandgap semiconductor material with excellent performance, has shown great application potential in many high-tech fields, such as power electronics, optoelectronics, new energy vehicles, and aerospace. Among them, β-silicon carbide has attracted much attention due to its unique crystal structure and electrical properties.
[0003] Traditional methods for synthesizing β-silicon carbide have many limitations. For example, although the Acheson method is a commonly used industrial method, it has high energy consumption, a long production cycle, and it is difficult to accurately control the purity and particle size distribution of the product. Although the chemical vapor deposition (CVD) method can produce high-purity β-silicon carbide, the equipment is complex and expensive, the output is low, and the cost is high, which is not suitable for large-scale industrial production. The solid-phase reaction method makes it difficult to ensure that the raw materials are fully and evenly mixed, which can easily lead to unstable product quality and high impurity content. These problems have seriously restricted the large-scale application and industrial development of β-silicon carbide. Summary of the invention
[0004] In view of the technical problems mentioned in the background technology, the present invention provides a β-silicon carbide synthesis process.
[0005] The technical solution adopted by the present invention is: a β-silicon carbide synthesis process, which specifically includes the following steps:
[0006] Step 1: Use silicon powder as the silicon source, with an average particle size of d Si (Unit: μm), and its particle size distribution was measured by laser particle size analyzer;
[0007] Step 2: Place the silicon powder in a vacuum environment and heat it at 500° C. for 2 hours to remove impurities and moisture adsorbed on the surface;
[0008] Step 3: Calculate and control the amount of residual gas according to the ideal gas state equation PV=nRT (where P is the vacuum degree, V is the volume of the heating chamber, n is the amount of gas substance, R is the ideal gas constant, and T is the temperature) to ensure the pretreatment effect.
[0009] Step 4: Use high-purity nano-carbon powder as a carbon source, with an average particle size of d C (Unit: nm) measured by transmission electron microscopy;
[0010] Step 5, calcining the carbon powder at 1000° C. for 1 h in an argon atmosphere;
[0011] Step 6: Construct a pulsed laser induced plasma reaction chamber: Made of quartz material, the inner wall is ultra-precision polished, and the roughness Ra is less than 0.05μm. The reaction chamber is equipped with a high-energy pulse laser with a laser wavelength of 1064nm, a pulse width of 10ns, and a pulse energy of E p Adjustable within the range of 100-500mJ;
[0012] Step 7: The laser beam is focused on the reaction area through a lens with a focal length f of 200 mm. The spot size and energy distribution of the beam in the reaction area are calculated and optimized to allow the laser energy to be efficiently coupled to the raw material powder to induce a plasma reaction.
[0013] Step 8: Weigh the pre-treated silicon powder and carbon powder according to the stoichiometric ratio of Si:C = 1:1, place them in a planetary ball mill, use high-hardness tungsten carbide balls as the ball-to-material ratio of 20:1, and rotate the ball mill at 500 rpm for a ball milling time of t m 6h,
[0014] Step 9: Press the mixed powder into a sheet with a diameter of 30 mm and a thickness of 5 mm on a four-column hydraulic press at a pressure of 30 MPa. (where ρ is the density after compaction, ρ 0 is the initial powder density, P is the pressing pressure, K and n are material constants to calculate the compaction degree of the sheet;
[0015] Step 10: Place the pressed slice on the sample stage of the reaction chamber and evacuate to 10 -3 Pa, and then high-purity argon is introduced as the protective gas and plasma working gas, the gas flow rate Q is 50sccm, and the flow velocity distribution and residence time of the gas in the reaction chamber are calculated according to the gas kinetics theory to ensure the stability of the reaction environment;
[0016] Step 11: Turn on the pulse laser and emit laser pulses at a frequency of 10 Hz. Silicon powder and carbon powder react rapidly in the plasma environment to generate β-silicon carbide. The reaction time is t r For 30 minutes, according to the chemical reaction kinetics formula (where C is the reactant concentration, k is the reaction rate constant, and n is the reaction order) to estimate the reaction progress and product formation rate;
[0017] Step 12: After the reaction is completed, turn off the laser and gas valve, and take out the sample after the reaction chamber cools to room temperature.
[0018] In one embodiment, in step 1, according to the formula (where ρ Siis the density of silicon, which is 2.33 g / cm 3 ) Calculate its specific surface area S Si (Unit: m 2 / g);
[0019] According to the formula Calculate the volume of a single toner particle, and then calculate the volume of the toner particle according to the toner mass and density (ρ C , value 2.25g / cm 3 ) Calculate its particle number concentration N C ;
[0020] In step 5, according to the Arrhenius equation (where k is the reaction rate constant, A is the pre-exponential factor, E a The effect of calcination on the reaction activity was estimated by using the activation energy, R the ideal gas constant, and T the calcination temperature.
[0021] In one embodiment, in step 7, according to Gaussian beam propagation theory, (W(z) is the beam radius, w 0 is the beam waist radius, z is the propagation distance, is the Rayleigh length), so as to calculate and optimize the spot size and energy distribution of the light beam in the reaction area.
[0022] In one embodiment, in step eight, according to the ball motion trajectory formula v=ωr (where v is the ball linear velocity, ω is the angular velocity, and r is the ball radius) and the collision energy formula (where m is the mill mass) Calculate the energy input during the ball milling process to ensure that the raw materials are fully and evenly mixed to achieve molecular level uniformity.
[0023] In one embodiment, in step 11, the laser pulse energy E p Set to 300mJ, the laser irradiates the surface of the thin film to generate high-temperature and high-pressure plasma. According to the laser energy absorption formula Q abs =αI 0 (1-e -αd )(where Q abs is the laser energy absorbed per unit area, α is the absorption coefficient of the material, I 0 is the laser intensity, d is the material thickness) and the plasma temperature formula (where T e is the electron temperature, k B is the Boltzmann constant, N e is the electron number density) to calculate the energy absorption and temperature of the plasma
[0024] In one of the embodiments, the method further comprises using a high-speed camera and an emission spectrometer to monitor the morphology and spectrum of the plasma plume in real time during the reaction process;
[0025] Among them, by analyzing the changes in the intensity of the characteristic spectral lines of elements such as Si and C in the spectrum, according to the relationship between the spectral line intensity and the element concentration formula (where I is the spectral line intensity, h is Planck's constant, ν is the spectral line frequency, g is the upper energy level statistical weight, A ij is the transition probability, N i is the number of particles in the upper energy level, E ij is the transition energy, μ is the atomic or molecular mass) to calculate the concentration change of each element.
[0026] In one embodiment, step twelve further includes placing the sample in an ultrasonic cleaning machine, using anhydrous silicon ethanol as a cleaning medium, and the ultrasonic power P u is 500W, ultrasonic time t u 15min;
[0027] According to ultrasonic cavitation theory and cleaning effect formula Silicon (where R is the cleaning rate, ρ is the medium density, c is the speed of sound, P a is the sound pressure amplitude, P 0 The cleaning effect was calculated by removing impurities and unreacted raw materials from the sample surface. The cleaned sample was dried in a vacuum drying oven at 80 °C for 4 h. Silicon (where M is the water content of the sample, k d is the drying rate constant, M e To balance the moisture content) the drying process is controlled to obtain a clean β-silicon carbide product.
[0028] The beneficial effects of the present invention are as follows: compared with the prior art, the present invention utilizes pulsed laser induced plasma technology to enable the reaction to reach a high temperature and high pressure state in an instant, greatly accelerating the reaction process, shortening the synthesis time, and improving the purity and crystallinity of the product, solving the problems of low synthesis efficiency and poor product quality in the traditional method, and meeting the high performance requirements of the high-end field for β-silicon carbide materials. Through precise raw material pretreatment and high-energy ball milling mixing process, the uniform mixing of silicon powder and carbon powder at the molecular level is ensured, the contact area and reaction activity of the raw materials are improved, and the use of a closed reaction chamber and high-purity argon as the working gas reduces the emission of harmful gases and environmental pollution, solving the problems of high production cost and large environmental pollution in the traditional method. DETAILED DESCRIPTION
[0029] In the description of the present invention, it should be noted that the terms "front", "up", "down", "left", "right", "vertical", "horizontal" and the like to indicate directions or positional relationships are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present invention.
[0030] In order to solve the problems existing in the background technology, the present application proposes the following technical solution: a β-silicon carbide synthesis process, specifically comprising the following steps:
[0031] Step 1: Use silicon powder as the silicon source, with an average particle size of d Si (Unit: μm), and its particle size distribution was measured by laser particle size analyzer;
[0032] In step 1, according to the formula (where ρ Si is the density of silicon, which is 2.33 g / cm 3 ) Calculate its specific surface area S Si (Unit: m 2 / g);
[0033] The above technical solution is explained as follows: by measuring the particle size distribution of silicon powder with a laser particle size analyzer, the particle situation of silicon powder can be accurately grasped. Secondly, by calculating the specific surface area of silicon powder according to a given formula, the surface characteristics of silicon powder can be further understood. The specific surface area is a key parameter in catalysis, adsorption and other processes. Understanding the specific surface area of silicon powder helps to optimize the relevant chemical reactions and physical processes involving silicon powder, improve reaction efficiency and reduce resource waste.
[0034] Step 2: Place the silicon powder in a vacuum environment and heat it at 500° C. for 2 hours to remove impurities and moisture adsorbed on the surface;
[0035] Step 3: Calculate and control the amount of residual gas according to the ideal gas state equation PV=nRT (where P is the vacuum degree, V is the volume of the heating chamber, n is the amount of gas substance, R is the ideal gas constant, and T is the temperature) to ensure the pretreatment effect.
[0036] Step 4: Use high-purity nano-carbon powder as a carbon source, with an average particle size of d C (Unit: nm) measured by transmission electron microscopy;
[0037] Step 5, calcining the carbon powder at 1000° C. for 1 h in an argon atmosphere;
[0038] In step 5, according to the Arrhenius equation (where k is the reaction rate constant, A is the pre-exponential factor, E aThe effect of calcination on the reaction activity was estimated by using the activation energy, R the ideal gas constant, and T the calcination temperature.
[0039] The above technical solution is explained as follows: vacuum heating treatment of silicon powder can effectively remove impurities and moisture adsorbed on its surface, which helps to improve the purity of subsequent reactions and ensure product quality. Secondly, in step three, the ideal gas state equation is used to calculate and control the amount of residual gas. This precise control method can ensure the consistency of the pretreatment effect, which is crucial for production processes that require high-precision raw material processing. Step four uses high-purity nano-carbon powder as a carbon source and accurately measures its particle size, which is conducive to accurately controlling the proportion of raw materials in subsequent reactions, thereby ensuring the stability of product performance. In step five, the Arrhenius equation is used to estimate the effect of calcination on the reaction activity, which can scientifically optimize the calcination process parameters, improve reaction efficiency, reduce energy waste and production costs, and ultimately achieve better product performance and economic benefits in fields such as material synthesis.
[0040] Step 6: Construct a pulsed laser induced plasma reaction chamber: Made of quartz material, the inner wall is ultra-precision polished, and the roughness Ra is less than 0.05μm. The reaction chamber is equipped with a high-energy pulse laser with a laser wavelength of 1064nm, a pulse width of 10ns, and a pulse energy of E p Adjustable within the range of 100-500mJ;
[0041] Step 7: The laser beam is focused on the reaction area through a lens with a focal length f of 200 mm. The spot size and energy distribution of the beam in the reaction area are calculated and optimized to allow the laser energy to be efficiently coupled to the raw material powder to induce a plasma reaction.
[0042] Among them, in step 7, according to Gaussian beam propagation theory (W(z) is the beam radius, w 0 is the beam waist radius, z is the propagation distance, is the Rayleigh length), so as to calculate and optimize the spot size and energy distribution of the light beam in the reaction area.
[0043] The above technical solution is explained as follows: The reaction chamber is made of quartz material and is ultra-precision polished, with a roughness as low as 0.05μm or less, which can reduce impurity contamination during the reaction and ensure the purity of the reaction. Secondly, the high-energy pulse laser is equipped with adjustable pulse energy (100-500mJ), specific pulse width (10ns) and wavelength (1064nm). This precise parameter control can be flexibly adjusted according to different reaction requirements to improve the controllability and efficiency of the reaction. Furthermore, by focusing the laser beam with a lens with a focal length of 200mm, the spot size and energy distribution can be accurately calculated and optimized to ensure that the laser energy is efficiently coupled to the raw material powder to induce a plasma reaction, which helps to improve the consistency of the reaction and the quality of the product.
[0044] Step 8: Weigh the pre-treated silicon powder and carbon powder according to the stoichiometric ratio of Si:C = 1:1, place them in a planetary ball mill, use high-hardness tungsten carbide balls as the ball-to-material ratio of 20:1, and rotate the ball mill at 500 rpm for a ball milling time of t m 6h;
[0045] Among them, in step eight, according to the ball motion trajectory formula v = ωr (where v is the ball linear velocity, ω is the angular velocity, and r is the ball radius) and the collision energy formula (where m is the mill mass) Calculate the energy input during the ball milling process to ensure that the raw materials are fully and evenly mixed to achieve molecular level uniformity.
[0046] Step 9: Press the mixed powder into a sheet with a diameter of 30 mm and a thickness of 5 mm on a four-column hydraulic press at a pressure of 30 MPa. (where ρ is the density after compaction, ρ 0 is the initial powder density, P is the pressing pressure, K and n are material constants to calculate the compaction degree of the sheet;
[0047] The above technical solution is explained as follows: In step eight, the raw materials are weighed according to the precise stoichiometric ratio and mixed in a planetary ball mill. The energy input is calculated using the ball motion trajectory formula and the collision energy formula to ensure that the raw materials can reach molecular uniformity. This can reduce problems such as local reaction anomalies caused by uneven mixing. In step nine, the mixed powder is pressed into thin sheets, and the compaction degree is calculated using the relationship formula between pressure and compaction degree. This precise control can make the thin sheets have good mechanical strength and suitable density, which is convenient for subsequent reaction operations and ensures the stability of the reaction process. It is also beneficial to improve the reaction efficiency and the quality of the final product.
[0048] Step 10: Place the pressed slice on the sample stage of the reaction chamber and evacuate to 10 -3Pa, and then high-purity argon is introduced as the protective gas and plasma working gas, the gas flow rate Q is 50sccm, and the flow velocity distribution and residence time of the gas in the reaction chamber are calculated according to the gas kinetics theory to ensure the stability of the reaction environment;
[0049] Step 11: Turn on the pulse laser and emit laser pulses at a frequency of 10 Hz. Silicon powder and carbon powder react rapidly in the plasma environment to generate β-silicon carbide. The reaction time is t r For 30 minutes, according to the chemical reaction kinetics formula (where C is the reactant concentration, k is the reaction rate constant, and n is the reaction order) to estimate the reaction progress and product formation rate;
[0050] Among them, in step 11, the laser pulse energy E p Set to 300mJ, the laser irradiates the surface of the thin film to generate high-temperature and high-pressure plasma. According to the laser energy absorption formula Q abs =αI 0 (1-e -αd )(where Q abs is the laser energy absorbed per unit area, α is the absorption coefficient of the material, I 0 is the laser intensity, d is the material thickness) and the plasma temperature formula (where T e is the electron temperature, k B is the Boltzmann constant, N e is the electron number density) to calculate the energy absorption and temperature of the plasma.
[0051] The above technical solution is explained as follows: Step 10 uses gas kinetics theory to ensure the stability of the reaction environment by precisely controlling the vacuum degree of the reaction chamber, introducing high-purity argon gas and reasonably setting the gas flow rate, which helps reduce impurity interference and ensure the smooth progress of the reaction. In step 11, laser pulses are emitted at a specific frequency to cause silicon powder and carbon powder to undergo a chemical reaction to generate β-silicon carbide. The chemical reaction kinetics formula can be used to estimate the reaction process and product generation rate, which helps to accurately control the production process. In addition, by setting the laser pulse energy and combining the laser energy absorption formula and the plasma temperature formula to calculate the energy absorption and temperature of the plasma, the reaction conditions can be optimized, the reaction efficiency can be improved, and the synthesis quality of β-silicon carbide can be ensured.
[0052] Step 12: After the reaction is completed, turn off the laser and gas valve, and take out the sample after the reaction chamber cools to room temperature.
[0053] According to the formula Calculate the volume of a single toner particle, and then calculate the volume of the toner particle according to the toner mass and density (ρ C, value 2.25g / cm 3 ) Calculate its particle number concentration N C ;
[0054] Among them, step 12 also includes placing the sample in an ultrasonic cleaning machine, using silicon anhydrous ethanol as a cleaning medium, and the ultrasonic power P u is 500W, ultrasonic time t u 15min;
[0055] According to ultrasonic cavitation theory and cleaning effect formula Silicon (where R is the cleaning rate, ρ is the medium density, c is the speed of sound, P a is the sound pressure amplitude, P 0 The cleaning effect was calculated by removing impurities and unreacted raw materials from the sample surface. The cleaned sample was dried in a vacuum drying oven at 80 °C for 4 h. Silicon (where M is the water content of the sample, k d is the drying rate constant, M e To balance the moisture content) the drying process is controlled to obtain a clean β-silicon carbide product.
[0056] The above technical solution is explained as follows: by accurately calculating the volume and particle number concentration of carbon powder particles through formulas, the raw material characteristics can be accurately grasped, which is helpful to optimize reaction conditions and improve product quality. Secondly, placing the sample in an ultrasonic cleaning machine, using silicon anhydrous ethanol as the cleaning medium, and operating according to ultrasonic cavitation theory and cleaning effect formulas, impurities and unreacted raw materials on the sample surface can be effectively removed to ensure the purity of the product. Furthermore, drying in a vacuum drying oven and controlling the drying process according to the drying kinetics formula can avoid product defects caused by improper drying and ensure the stability of product quality.
[0057] Other embodiments may include using a high-speed camera and an emission spectrometer to monitor the morphology and spectrum of the plasma plume in real time during the reaction process;
[0058] Among them, by analyzing the changes in the intensity of the characteristic spectral lines of elements such as Si and C in the spectrum, according to the relationship between the spectral line intensity and the element concentration formula (where I is the spectral line intensity, h is Planck's constant, ν is the spectral line frequency, is the statistical weight of the upper energy level, A ij is the transition probability, N i is the number of particles in the upper energy level, E ij is the transition energy, μ is the atomic or molecular mass) to calculate the concentration change of each element.
[0059] The above technical solution is explained as follows: The method of calculating the concentration change of each element by analyzing the change in the intensity of the characteristic spectral lines of elements such as Si and C in the spectrum has many beneficial effects. It can accurately monitor the dynamic changes of the concentration of elements during the reaction, which helps to gain a deeper understanding of the reaction mechanism and process, and provide data support for optimizing the reaction conditions. Secondly, the calculation is based on the relationship formula between the spectral line intensity and the element concentration, which makes the analysis process have a scientific basis and quantitative standards, avoids the errors caused by subjective judgment, and improves the accuracy and reliability of the analysis results.
[0060] In summary, the present invention uses pulsed laser induced plasma technology to make the reaction reach a high temperature and high pressure state in an instant, greatly accelerating the reaction process, shortening the synthesis time, and improving the purity and crystallinity of the product, solving the problems of low synthesis efficiency and poor product quality in traditional methods, and meeting the high performance requirements of high-end fields for β-silicon carbide materials. Through precise raw material pretreatment and high-energy ball milling mixing process, the uniform mixing of silicon powder and carbon powder at the molecular level is ensured, the contact area and reaction activity of the raw materials are improved, and the use of a closed reaction chamber and high-purity argon as the working gas reduces the emission of harmful gases and environmental pollution, solving the problems of high production cost and large environmental pollution in traditional methods.
[0061] While the embodiments of the present invention have been shown and described, it will be apparent to those skilled in the art that the scope of the present invention is defined by the appended claims and their equivalents.
Claims
1. A β-silicon carbide synthesis process, characterized in that: The specific steps include: Step 1: Use silicon powder as the silicon source, with an average particle size of d Si (Unit: μm), and its particle size distribution was measured by laser particle size analyzer; Step 2: Place the silicon powder in a vacuum environment and heat it at 500° C. for 2 hours to remove impurities and moisture adsorbed on the surface; Step 3: Calculate and control the amount of residual gas according to the ideal gas state equation PV=nRT (where P is the vacuum degree, V is the volume of the heating chamber, n is the amount of gas substance, R is the ideal gas constant, and T is the temperature) to ensure the pretreatment effect. Step 4: Use high-purity nano-carbon powder as a carbon source, with an average particle size of d C (Unit: nm) measured by transmission electron microscopy; Step 5, calcining the carbon powder at 1000° C. for 1 h in an argon atmosphere; Step 6: Construct a pulsed laser induced plasma reaction chamber: Made of quartz material, the inner wall is ultra-precision polished, and the roughness Ra is less than 0.05μm. The reaction chamber is equipped with a high-energy pulse laser with a laser wavelength of 1064nm, a pulse width of 10ns, and a pulse energy of E p Adjustable within the range of 100-500mJ; Step 7: The laser beam is focused on the reaction area through a lens with a focal length f of 200 mm. The spot size and energy distribution of the beam in the reaction area are calculated and optimized to allow the laser energy to be efficiently coupled to the raw material powder to induce a plasma reaction. Step 8: Weigh the pre-treated silicon powder and carbon powder according to the stoichiometric ratio of Si:C = 1:1, place them in a planetary ball mill, use high-hardness tungsten carbide balls as the ball-to-material ratio of 20:1, and rotate the ball mill at 500 rpm for a ball milling time of t m 6h, Step 9: Press the mixed powder into a sheet with a diameter of 30 mm and a thickness of 5 mm on a four-column hydraulic press at a pressure of 30 MPa. (where ρ is the density after compaction, ρ0 is the initial powder density, P is the pressing pressure, and K and n are material constants for calculating the compaction degree of the sheet; Step 10: Place the pressed slice on the sample stage of the reaction chamber and evacuate to 10 -3 Pa, and then high-purity argon is introduced as the protective gas and plasma working gas, the gas flow rate Q is 50sccm, and the flow velocity distribution and residence time of the gas in the reaction chamber are calculated according to the gas kinetics theory to ensure the stability of the reaction environment; Step 11: Turn on the pulse laser and emit laser pulses at a frequency of 10 Hz. Silicon powder and carbon powder react rapidly in the plasma environment to generate β-silicon carbide. The reaction time is t r For 30 minutes, according to the chemical reaction kinetics formula (where C is the reactant concentration, k is the reaction rate constant, and n is the reaction order) to estimate the reaction progress and product formation rate; Step 12: After the reaction is completed, turn off the laser and gas valve, and take out the sample after the reaction chamber cools to room temperature.
2. A β-silicon carbide synthesis process according to claim 1, characterized in that: in, In step 1, according to the formula (where ρ Si is the density of silicon, which is 2.33 g / cm 3 ) Calculate its specific surface area S Si (Unit: m 2 / g); According to the formula Calculate the volume of a single toner particle, and then calculate the volume of the toner particle according to the toner mass and density (ρ C , value 2.25g / cm 3 ) Calculate its particle number concentration N C ; In step 5, according to the Arrhenius equation (where k is the reaction rate constant, A is the pre-exponential factor, E a The effect of calcination on the reaction activity was estimated by using the activation energy, R the ideal gas constant, and T the calcination temperature.
3. A β-silicon carbide synthesis process according to claim 1, characterized in that: In step 7, according to Gaussian beam propagation theory (W(z) is the beam radius, w0 is the beam waist radius, z is the propagation distance, is the Rayleigh length), thereby calculating the spot size and energy distribution of the light beam in the reaction area.
4. A β-silicon carbide synthesis process according to claim 1, characterized in that: In step 8, according to the ball motion trajectory formula v = ωr (where v is the ball linear velocity, ω is the angular velocity, and r is the ball radius) and the collision energy formula (where m is the mill mass) Calculate the energy input during the ball milling process to ensure that the raw materials are fully and evenly mixed to achieve molecular level uniformity.
5. A β-silicon carbide synthesis process according to claim 1, characterized in that: In step 11, the laser pulse energy E p Set to 300mJ, the laser irradiates the surface of the thin film to generate high-temperature and high-pressure plasma. According to the laser energy absorption formula Q abs =αI0(1-e -αd )(where Q abs is the laser energy absorbed per unit area, α is the absorption coefficient of the material, I0 is the laser intensity, d is the material thickness) and the plasma temperature formula (where T e is the electron temperature, k B is the Boltzmann constant, N e is the electron number density) to calculate the energy absorption and temperature of the plasma.
6. A β-silicon carbide synthesis process according to claim 1, characterized in that: It also includes real-time monitoring of the morphology and spectrum of the plasma plume using a high-speed camera and an emission spectrometer during the reaction; Among them, by analyzing the changes in the intensity of the characteristic spectral lines of elements such as Si and C in the spectrum, according to the relationship between the spectral line intensity and the element concentration formula (where I is the spectral line intensity, h is Planck's constant, ν is the spectral line frequency, is the statistical weight of the upper energy level, A ij is the transition probability, N i is the number of particles in the upper energy level, E ij is the transition energy, μ is the atomic or molecular mass) to calculate the concentration change of each element.
7. A β-silicon carbide synthesis process according to claim 6, characterized in that: Step 12 also includes placing the sample in an ultrasonic cleaning machine, using anhydrous ethanol as a cleaning medium, and the ultrasonic power P u is 500W, ultrasonic time t u 15min; According to the ultrasonic cavitation theory and cleaning effect formula Silicon (where R is the cleaning rate, ρ is the medium density, c is the speed of sound, P a The cleaning effect was calculated by removing impurities and unreacted raw materials from the sample surface. The cleaned sample was dried in a vacuum drying oven at 80 °C for 4 h. Silicon (where M is the water content of the sample, k d is the drying rate constant, M e To balance the moisture content) the drying process is controlled to obtain a clean β-silicon carbide product.