321 results about "Cooling rates" patented technology

The invention belongs to the technical field of cell cryopreservation, and relates to a cryopreservation method based on ultrasonic ice planting. In the method, the nucleation temperature of ice planting is less than-9 DEG C, and the cooling rate from nucleation to icing is less than 5 DEG C / min. Compared with the prior art, the method has the advantages that the time required for cryopreservation of the cells is remarkably shortened, meanwhile, damage to the cells caused by ice crystals generated in the cooling process is reduced, and the problem that an existing cell cryopreservation cooling method cannot meet the nucleation and freezing uniformity of a cell solution in the cooling process is solved.

The invention belongs to the field of production control, and particularly discloses a control method of a thick-wall optical product precision injection molding hot runner system, which comprises the following steps of: acquiring mold geometric data of local thickness distribution in a mold-containing cavity along a melt flowing direction, calculating theoretical cooling time constants of each region by combining material thermophysical parameters, and calculating the cooling time constant of each region; establishing a thickness-cooling rate mapping relation model; predicting the time when the melt reaches each area and the effective cooling time according to an injection time sequence; solving a temperature compensation value of a heating area corresponding to the hot runner by taking the minimum final temperature variance when the key area is ejected as a target; and finally, dynamically applying a compensation value according to a time sequence before the melt arrives, and withdrawing / adjusting after region filling is completed or a pressure maintaining stage is entered. The invention can balance the temperature field of the mold cavity, reduce the refractive index gradient and shrinkage defect, improve the optical performance and yield of the product, and is suitable for precise injection molding of the thick-wall optical product.

The invention discloses a reconfigurable casting process module hierarchical control method, which comprises the following steps of: firstly, acquiring a multi-source sensor data stream generated in a casting task execution process, the data comprising key process parameters such as temperature, pressure, flow velocity and the like; based on this data stream, an initial condition feature set for characterizing the dynamic condition is determined. And then, carrying out segmented working condition optimization processing on the feature set by utilizing a hierarchical decoupling regulation model, and obtaining an optimized working condition feature set through system coupling dissociation and random disturbance stripping. And finally, performing feature reconstruction processing on the optimization feature set, and generating an optimization control instruction accurately matched with the current casting process to adjust the pouring speed, the cooling rate or the pressure parameter in real time, thereby realizing closed-loop optimization control of the casting process. According to the method, the control precision and the process stability under complex working conditions are effectively improved.

The invention relates to the technical field of fault detection, in particular to an electrical equipment fault diagnosis method and system, and the method comprises the following steps: constructing a ratio group of a trigger incremental sequence quantity and a frequency spectrum cluster set based on a partial discharge pulse interval, deducing impedance frequency boundary migration, analyzing a conductor heating and cooling rate difference, and forming thermal response lag information. According to the method, frequency spectrum energy evolution characteristics are extracted through partial discharge pulse interval dynamic behaviors, a frequency migration path is constructed to reflect an impedance boundary fluctuation process, hysteresis effect characteristics are extracted in combination with thermal inertia response differences in a temperature rise stage, and the impedance boundary fluctuation is determined. And analyzing a voltage and current phase fluctuation rule and deducing a change trend of a combined feature, establishing a layer-by-layer progressive judgment logic between multi-stage dynamic coupling features, realizing evolutionary process tracking from local disturbance to a global abnormal state, and improving a fine-grained identification level of an abnormal mechanism in an electrical equipment operation behavior.

The invention provides a hafnium oxide-based ferroelectric film annealing process with a low thermal budget and a hafnium oxide-based ferroelectric film, and relates to the field of ferroelectric films, the hafnium oxide-based ferroelectric film is subjected to multiple low-temperature rapid annealing cycles, and the hafnium oxide-based ferroelectric film annealing process comprises the following steps: heating to an annealing temperature of 400 DEG C at a heating rate of 10-80K / s, keeping the temperature for 15-120s, and cooling at a cooling rate of not less than 10K / s, and after cooling to room temperature, carrying out next annealing cycle. The internal defect distribution of the thin film is changed through repeated rapid annealing circulation; and multiple times of rapid cooling are introduced, so that multiple times of enhanced stress is generated in the thin film, the hafnium oxide phase change potential barrier is cooperatively regulated and controlled, conversion from a non-ferroelectric high-temperature tetragonal phase to a ferroelectric orthogonal phase is promoted, and the requirement for the high annealing temperature is avoided.

The invention provides a cooling rate optimization control method and system for continuous cooling crystallization, and the method comprises the steps: collecting crystal slurry concentration data and temperature data of each stage of crystallization tank in real time; the crystal slurry concentration data, the temperature data and the feeding flow data are input into a deep learning model, and a prediction result is obtained; based on the prediction result and crystal mush concentration data, dynamically adjusting the cooling rate of each stage of crystallizing tank and the addition amount of a co-crystallizing solvent; and feeding back an outlet crystal mush concentration signal of the last-stage crystallizing tank to the solid-liquid separation unit, and adjusting the running rotating speed of the solid-liquid separation unit in a linkage manner. According to the cooling rate optimization control method and system for continuous cooling crystallization, prospective correction of the cooling rate is carried out by using the predicted supersaturation degree, and adjustment of the additive amount of the auxiliary crystallization solvent is carried out by using the predicted crystal particle size distribution; and finally, an outlet concentration signal of the last-stage crystallizing tank is fed back to the solid-liquid separation unit in real time to adjust the separation rotating speed in a linkage manner, so that the crystal particle size deviation is reduced, and the triazole crystallization recovery rate is improved.

The invention discloses a mass concrete temperature control construction method and system based on phase change energy storage, and the method comprises the steps: S100, building a BIM model for a concrete member pouring region according to a design size, setting a temperature sensor in a concrete member to monitor data in real time, and predicting a temperature field in combination with the BIM model; s200, the space between the conventional cooling water pipe and the concrete protection layer is filled with phase change microcapsules in a gradient density mode, a phase change energy storage buffer layer is formed, and transfer of heat to the interior of the concrete member is delayed; s300, according to the predicted temperature field, the water inlet flow and the water temperature are dynamically adjusted, the temperature peak is controlled, and the cooling rate is controlled; s400, fiber grating sensors are arranged at the four corners and the midspan of the concrete member, and the strain change rate is detected; and S500, establishing a digital twin temperature control platform, integrating temperature, humidity and strain data, constructing a three-dimensional thermodynamic model, predicting the temperature rise trend of the concrete member, and performing adaptive regulation and control on the temperature. Temperature difference inside and outside the concrete is controlled through phase change temperature control.

The invention provides a pipeline welding real-time feedback control method and system based on machine vision. According to the method, multi-modal data such as a three-dimensional point cloud, a temperature field and a welding seam image are synchronously collected, and key characteristics such as a pose deviation gradient, a cooling rate curve and a welding seam size sequence are extracted after time sequence alignment, filtering and correction fusion. And a CNN and LSTM mixed adaptive deep learning model is utilized to analyze the welding quality state in real time, and sub-optimal parameters are dynamically optimized based on a reinforcement learning strategy, or a three-level response mechanism including heat reduction input, expert knowledge base matching and precise repair is triggered to process defect early warning. The system has an incremental learning capability and can be self-optimized along with a control period. The full-flow intelligent monitoring, real-time feedback and self-adaptive accurate control of the welding process are achieved, and the welding quality and the automation level are remarkably improved.

The invention discloses a refrigeration control method based on inverter compressor control, which relates to the technical field of refrigeration equipment control, and comprises the following steps: acquiring operation data of a refrigeration system according to a preset period, and extracting a thermal response characteristic representing a cooling rate attenuation acceleration by performing differential processing on an indoor temperature; and calculating a thermal rebound sensitivity characteristic by combining the frequency change gradient. A thermal inertia potential energy index representing the heat storage load of the enclosure structure is generated through time domain accumulation processing, a nonlinear drift modulation model is constructed accordingly, and a virtual set temperature and a dynamic frequency lower limit value are generated. And finally calculating a basic adjusting frequency based on the virtual set temperature, and selecting the maximum value of the basic adjusting frequency and the lower limit value of the dynamic frequency as a target driving frequency. Through cooperation of algorithm soft traction and physical hard lifting, the problem of overshoot oscillation in a complex thermal environment is solved, and temperature control stability and energy saving performance are improved.

The invention discloses a T ferromagnetic annealing performance consistency optimization method based on reinforcement learning, and the method comprises the steps: collecting the annealing temperature, heat preservation time, magnetic field intensity, cooling rate and other key process parameters in real time through an industrial Internet of Things, and improving the data quality through normalization and multi-stage data cleaning processing; intelligent evaluation and label classification of the process state are realized by using a multi-layer neural network; a dynamic reward function weight is introduced in combination with a process state label, and a deep Q network reinforcement learning model is driven to perform strategy optimization; the method supports self-adaptive model updating of periodic data acquisition and strategy rapid switching under significant change of a process state, realizes intelligent cooperative closed-loop control of multiple parameters in the annealing process, and improves the operation stability of the annealing process and the consistency of material performance.

The application relates to a high-temperature nitriding preparation method of a cobalt-based high-temperature alloy by using nitride dispersion reinforcement, and belongs to the technical field of dispersion reinforcement materials. The cobalt-based high-temperature alloy profile is placed in a high-temperature nitriding furnace, the inner cavity of the nitriding furnace is vacuumized, the cobalt-based high-temperature alloy profile is in a vacuum environment, then argon is filled into the inner cavity of the nitriding furnace, and the temperature is raised to a set temperature of 1100-1200 DEG C; then a mixed gas atmosphere of nitrogen and argon is introduced into the inner cavity of the nitriding furnace, the flow speed is 80-120 mL / min, the cobalt-based high-temperature alloy profile is subjected to nitriding treatment in the furnace for a certain time, and after the high-temperature nitriding process is completed, the temperature is cooled to room temperature at a cooling rate of 20-40 DEG C / min. The method is aimed at cobalt-based high-temperature alloy wire or plate, high-temperature nitriding treatment is carried out in a mixed gas atmosphere of nitrogen and argon, stable nitrides are formed in the alloy organization to play a dispersion reinforcement role, and the problem that the strength of the cobalt-based high-temperature alloy is relatively low can be effectively solved.

This invention discloses a method for preparing a uniform microstructure on the surface of a containerless solidified niobium alloy for a space station, relating to the field of containerless materials science experimental technology. The method first screens for highly supercooled samples suitable for preparing a uniform microstructure using this method in containerless space station experiments; calculates or experimentally determines the primary phase dendrite growth rate, the cooling rate coefficient of radiative heat dissipation during the cooling stage, and the primary phase nucleation rate; and conducts containerless space station experiments to allow the niobium alloy to undergo deep supercooling and rapid solidification within a determined suitable supercooling range, thus obtaining a solidified alloy sample with a uniform surface microstructure. This invention actively controls the distribution of dendrites and eutectic phases, resulting in a surface microstructure with uniformly distributed dendrites and interdendritic eutectic phases.

This application relates to apparatus and methods for roll forming of high-refractive-index glass sheets. The method of forming a glass sheet includes: (a) forming a glass ribbon from molten glass using a pair of forming rollers; (b) reducing the horizontal temperature variation of the glass ribbon over 80% of its entire width before cooling to the glass transition temperature to 10°C or less; (c) controlling the cooling rate of the glass ribbon as it moves longitudinally downward in the solidification zone such that the glass ribbon has a first average cooling rate before cooling to the glass transition temperature and a second average cooling rate after cooling to the glass transition temperature, the first average cooling rate being less than the second average cooling rate; and (d) separating the glass sheet from the glass ribbon.

The invention relates to the technical field of rock mechanics experiments, and discloses a high-temperature rock strength testing method for eliminating thermal stress interference through active temperature control, and the method comprises the following steps: determining a temperature control cooling rate threshold value for eliminating thermal stress accumulation based on a temperature field-stress field coupling model; the rock sample is controlled to be heated to a target temperature value, heat preservation is conducted for a preset time length, the constant-temperature box containing the rock sample subjected to heat preservation is subjected to temperature-controlled cooling to the room temperature at the target temperature-controlled cooling rate not higher than the temperature-controlled cooling rate threshold value, and therefore the internal temperature field of the rock sample is made to change evenly; and carrying out mechanical strength test on the rock sample subjected to temperature-controlled cooling to obtain a test rock strength parameter without thermal stress interference. According to the invention, thermal stress accumulation caused by natural cooling can be effectively avoided, the precision and reliability of high-temperature rock strength testing are remarkably improved, measurement errors caused by thermal stress interference are reduced, and the engineering requirements of deep ultrahigh-temperature stratum rock mechanical property research are met.

This invention belongs to the field of semiconductor optoelectronic device manufacturing technology and discloses a multi-stage annealing process for ITO thin films, including the following steps: Step 1: Under high vacuum protection, the furnace temperature is raised from room temperature to a first temperature T1 and held for a first time; Step 2: The furnace temperature is raised to a higher second temperature T2 and held for a second time, without the need for oxygen introduction during the second holding stage; Step 3: While maintaining the second temperature T2, a third holding stage is performed, and oxygen is introduced during the third holding stage; Step 4: A controllable cooling process is performed, which includes at least a slow cooling stage under the oxygen atmosphere and a rapid cooling stage under an inert gas or extremely low oxygen concentration atmosphere. This invention achieves precise staged control of the ITO thin film crystallization process, oxygen vacancy filling, and interfacial reactions by precisely controlling the oxygen partial pressure and cooling rate at different temperature stages.

The invention discloses a melt separation titanium slag modification treatment method and system. The method comprises the steps that in the direct reduction-melt separation process, melt separation titanium slag components are regulated and controlled to enable the melt separation titanium slag to contain 40 wt%-60 wt% of TiO2 and 1.1 wt%-9 wt% of C, deslagging is conducted, after heat preservation melting is conducted on the melt separation titanium slag at the temperature of 1550-1600 DEG C for 30-60 minutes, slow cooling is conducted to 1200 DEG C at the cooling rate of 5-10 DEG C / min, then rapid cooling is conducted to 900 DEG C at the cooling rate of 20 DEG C / min or above, finally natural cooling is conducted to the room temperature, and modified slag is obtained. According to the method, regulation and control of components of the melt-separated titanium slag are combined with heat preservation, slow cooling, quenching and natural cooling, anosovite is directionally induced to serve as a main phase of the titanium slag, micronized spinel and an amorphous glass phase, titanium resources are enriched in the anosovite phase, and the modified titanium slag high in grade and good in activity is obtained; and the problems of low additional value, small utilization scale, poor economic benefit and the like of molten titanium slag products are solved.

A cooling system includes one or more cooling panels for affecting a cooling load in an environment. The cooling system also includes a heat exchanger coupled to the one or more cooling panels. Each cooling panel includes a film, a panel body, an inlet port, an outlet port, and a fluid path. The film's radiative properties allow it to achieve a temperature less than an environment temperature. The heat exchanger includes ports that are coupled to the fluid paths of the one or more cooling panels. A control system is used to control flow rates, flow paths, fluid temperatures, component temperatures, cooling rates, component operation, or other aspects of a cooling system. For example, the control system controls or monitors pumps, compressors, fans, valves, sensors, actuators, or a combination thereof.

This invention belongs to the field of aerospace composite material manufacturing technology, specifically relating to a method and equipment for forming thermoplastic composite strain energy rods. First, prepreg is laid up to form a preform, which is then pressed by a flatbed pre-pressing device to form a preform sheet intermediate. Subsequently, the preform intermediate is fed into a hot-pressing module with a central heating and two-end cooling gradient temperature field. It undergoes melting and molding in a high-temperature zone and controlled cooling in a low-temperature zone to achieve final shaping. Finally, the formed rod is cooled and shaped, then pulled out at a uniform speed by a traction device and coiled and collected by a winding device, achieving continuous production. The hot-pressing module of the supporting hot-pressing equipment is equipped with a zoned heating and integrated cooling system, which can precisely construct a gradient temperature field and control the cooling rate. This invention, by using gradient temperature control to precisely regulate the material's crystallization behavior and release internal stress, effectively ensures the straightness, dimensional stability, and consistent deployment performance of the strain energy rod, perfectly meeting the manufacturing requirements of strain energy rods for large deployable structures in spacecraft.

This invention relates to the field of concrete pouring technology, and discloses a method and system for regulating the cooling of hydration heat in large-volume concrete based on temperature difference control. The method includes the following steps: Step S101, constructing a thickness temperature profile; Step S102, calculating the zone temperature difference and the cooling rate in the middle section; Step S103, calculating the equivalent age field; Step S104, calculating the time-varying elastic modulus and relaxation time; Step S105, constructing a base constraint weighting function; Step S106, calculating the constrained viscoelastic thermal stress field; Step S107, calculating the potential energy centroid drift intensity; Step S108, outputting control commands. This invention achieves multi-factor coupled calculation and multi-objective collaborative optimization for regulating the cooling of hydration heat in large-volume concrete, ensuring that cooling regulation aligns with the core requirements of crack resistance in engineering projects, thereby reducing the possibility of hydration heat cracking in concrete.

The invention discloses a method for regulating and controlling the exchange bias performance of Ni-Mn-based alloy in dual modes by changing the homogenization cooling rate and the aging time, and belongs to the technical field of functional metal materials and spintronics. The invention aims to solve the technical problems that the existing Ni-Mn-based alloy excessively depends on component adjustment in the construction of the exchange bias effect, the exchange bias field / coercive force is difficult to configure as required, and the bias level still needs to be improved. The method comprises the following steps: 1, component design and smelting; 2, pipe sealing treatment of the alloy to be subjected to heat treatment; 3, homogenizing treatment and cooling; and 4, aging treatment. The method is used for changing the homogenizing cooling rate and the aging time to regulate and control the exchange bias performance of the Ni-Mn-based alloy in the dual mode.

The invention concerns a method for producing a 6xxx series aluminium sheet comprising the steps of homogenizing an ingot made from a 6XXX series aluminium alloy; cooling the homogenized ingot with a cooling rate in a range of from 150° C. / h to 2000° C. / h directly to the hot rolling starting temperature; hot rolling the ingot to a hot rolling final thickness and coiling at the hot rolling final thickness with such conditions that at least 90% recrystallization is obtained while controlling the temperatures of hot rolling, in particular the relationship between the hot rolling starting temperature and the hot rolling exit temperature and / or controlling the grain size after coiling; cold rolling to obtain a cold rolled sheet.

The invention discloses a cooling control system and method for salt bath quenching of bearing parts, and relates to the technical field of bearing heat treatment, and the cooling control system comprises a miniature simulation body which is arranged in a salt bath tank and comprises a sealing sleeve, a thermocouple temperature sensor and an electric heating element, and the thermocouple temperature sensor and the electric heating element are sealed in the sealing sleeve; the electric heating element is configured to be capable of actively heating the micro simulation body to a preset target temperature, immediately stopping heating and naturally cooling; and the thermocouple temperature sensor is configured to acquire temperature data of the miniature simulation body in a natural cooling process in real time. According to the cooling control system and method, the quenching intensity of salt bath quenching can be dynamically monitored in real time, a cooling characteristic curve is automatically generated through collected temperature data, a special control model is constructed by utilizing a self-learning algorithm, finally, the water supplementing amount is automatically and accurately adjusted according to the technological requirements, and the water supplementing efficiency is improved. And the cooling rate of the bearing part is stabilized in an ideal range.

The present application relates to heat shrink sleeve test technical field, especially to a kind of stress test system of heat shrink sleeve, comprising: test module, to carry out stress test to heat shrink sleeve;Detection module is connected with the test module, including with the clamping device is connected to detect the area of wear area in clamping surface visual sensor;Clamping adjustment module is connected with the test module, to determine the micro-tilt angle compensation of clamping surface according to wear area area proportion in clamping surface;Sampling adjustment module is connected with the detection module and the clamping adjustment module respectively, to determine the weight distribution coefficient of low temperature sampling point according to the difference between actual temperature and target temperature in heating process;Cooling adjustment module is connected with the test module and the sampling adjustment module respectively, to determine cooling rate limit value according to cooling pipe surface dew coverage area proportion.The present application improves the stress test stability of heat shrink sleeve.

Provided are a polyethylene having excellent processability and capable of reducing an injection molding defect rate, and a method of preparing the same. The polyethylene has an integral value in the region where the Log Mw is 5.5 or more in a GPC curve, wherein the x-axis is log Mw and the y-axis is dw / dlogMw, of 9% or less of the total integral value: and has a ratio (Tc10 / Tc40) of a crystallization temperature (Tc10) measured at a cooling rate of 10° C. / min to a crystallization temperature (Tc40) measured at a cooling rate of 40° C. / min of less than 1.04.

The invention relates to a heat treatment regulation and control method for equiaxial alpha volume fraction of a laser deposition state titanium-based composite material, which comprises the following steps of: heating a sample of the laser deposition state titanium-based composite material to a heating final temperature along with a furnace, immediately cooling the sample to a cooling final temperature along with the furnace at a cooling speed of 1-15 DEG C / min, and taking out the sample from a heat treatment furnace after the sample is cooled to the cooling final temperature, thereby obtaining the equiaxial alpha volume fraction of the laser deposition state titanium-based composite material. The invention further provides a laser deposition state titanium-based composite material obtained through the method, the laser deposition state titanium-based composite material is a TiB2 reinforced Ti65 composite material, and compared with the laser deposition state titanium-based composite material, the yield strength at the room temperature is not lower than 850 MPa, and the tensile strength is not changed or slightly improved by 20-50 MPa; and under the condition that the tensile strength is not lower than 1150 MPa, the room-temperature ductility is improved by 100%-150%.

The utility model relates to the technical field of automobile water chamber processing, in particular to automatic water chamber shaping equipment with high cooling rate, which comprises a cabinet body, the cabinet further comprises air holes, base plates, connecting flanges, guide pipes, an air pump, connecting pipes and flow guide holes, a frame is arranged on the upper surface of the cabinet body, symmetrical mounting plates are arranged on the left side and the right side of the inner surface of the frame, first bases are arranged at the inner positions of the upper surfaces of the two mounting plates, and first clamping plates are arranged on the upper surfaces of the first bases; the air pump is arranged, the first clamping plate and the second clamping plate are hollow plates, the air pump can convey cold air flow into the first clamping plate through the guide pipe during operation, and the cold air flow flows into the second clamping plate through the connecting pipe at the rear end of the first clamping plate, so that air in the first clamping plate and the second clamping plate circulates; and the air holes are formed, so that the cooling effect on the base plate can be enhanced, and the cooling rate of the clamping face is increased.

The invention relates to the technical field of photovoltaic glass processing, and discloses a tempering process of high-strength 2.0 mm coated photovoltaic glass, the process comprises cleaning treatment, coating treatment, curing treatment, tempering treatment and post-treatment, surface impurities and moisture are removed through the cleaning treatment, meanwhile, a nano-scale porous silicon dioxide coating layer is formed through the coating treatment, and the surface of the photovoltaic glass is subjected to the post-treatment. The film layer is preliminarily cured through curing treatment, so that the surface cleanness of the glass and the completeness of the coating layer are ensured, and a good foundation is provided for toughening treatment; through partition temperature control of heating treatment and cooperation of a quartz roller transmission system and driving of a variable-frequency synchronous motor and a servo motor, it is guaranteed that glass passes through all heating areas at a constant speed, the heating process is uniform and stable, meanwhile, a high-pressure air grid system is adopted for cooling treatment for quenching, air grid parameters are controlled, and cooling rate matching is guaranteed; and defects caused by uneven stress distribution are avoided.

The utility model relates to a structure for accelerating the environmental cooling rate in a cavity and enhancing the temperature uniformity. The structure comprises a box body, the inner side wall of the box body is connected with blades, the inner side wall of the box body is connected with a storage rack, the bottom face of the box body is connected with an evaporation plate, the blades are located above the storage rack, and the lower end face of the storage rack is connected with a flow guide plate. The front end of the box body is connected with the box door. The number of the blades can be multiple. And the blades are connected with a variable frequency motor. A heat preservation layer is arranged on the outer wall of the box body. And a blade housing is arranged on the outer side of the blade. And the evaporation plate is connected with a refrigerant conveying pipe. The utility model aims to overcome the defects in the prior art, and provides the structure for accelerating the environment cooling rate in the cavity and enhancing the temperature uniformity, so that the temperature reduction rate in the cavity is accelerated; and the uniformity of the temperature in the cavity is enhanced.

The invention relates to the technical field of lithium ion batteries, in particular to a preparation method of a low-expansion silicon-carbon negative electrode material with a gradient coating layer, which comprises the following steps: 1, providing a silicon source and a carbon source; 2, providing a coating precursor; 3, performing high-temperature carbonization on the material subjected to the primary heat treatment in an inert atmosphere, and gradually increasing the carbonization temperature from the primary heat treatment temperature to a target carbonization temperature, so that the gradient coating layer is converted into a carbon-based gradient coating layer; and 4, naturally cooling the carbonized material to room temperature, determining the cooling rate by controlling the thermal stress of the material, then grinding and screening, adjusting the grinding strength by monitoring the particle size distribution, and determining the screening aperture according to the target application demand to obtain the low-expansion silicon-carbon negative electrode material with the gradient coating layer. The gradient coating layer effectively inhibits the volume expansion of the silicon-carbon composite material in the charge-discharge process, reduces the pulverization of the material, and improves the cycle life and the capacity retention rate.

The application relates to the field of coating technology and discloses a coating equipment, which comprises an equipment main body, a cooling assembly and a driving mechanism, the equipment main body is provided with a coating cavity, the cooling assembly is arranged in the coating cavity, the driving mechanism is connected to the equipment main body, and the power output end of the driving mechanism is connected with the cooling assembly; the driving mechanism is used for driving the cooling assembly to move so as to shorten the distance between the cooling assembly and a substrate holder. Since the cooling assembly can move under the action of the driving mechanism to shorten the distance with the substrate holder, the heat on the substrate holder is transferred to the cooling assembly at a faster rate, and therefore, the cooling rate of the coating equipment on the substrate holder is higher.