430 results about "Thermal fatigue" patented technology

The invention discloses a method and a system for monitoring the reliability of a photovoltaic converter in a special plateau environment. The method comprises the following steps: firstly, acquiring electrical quantity, temperature quantity, environment quantity and operation quantity, filtering abnormal data, and realizing accurate alignment of multi-frequency signals in combination with a dynamic time warping algorithm; secondly, constructing a plateau sensitive feature set, and optimizing feature quality through physical consistency check and three-stage feature selection; then, an IGBT thermal fatigue equation and a capacitance aging equation are fused to establish a health index evolution model, a Bayesian physical information neural network is used for prediction, and a high-reliability confidence interval is output through Monte Carlo sampling. And finally, dynamically correcting the residual life based on the comprehensive environment factor, and triggering a hierarchical maintenance decision according to the health index state, the residual life and the confidence interval width. The service life prediction precision of the photovoltaic converter in the plateau environment is remarkably improved, the operation and maintenance cost is effectively reduced, and the equipment operation reliability is enhanced.

The invention relates to a turbine blade global temperature field reconstruction method based on a multi-modal physical constraint network, and belongs to the technical field of aero-engine thermal management. Aiming at the problems of insufficient global heat conduction path modeling, lack of physical rules and blank region differentiation perception, carrying out normalization and position coding on sparse temperature measurement points to form a Transform encoder input sequence; extracting features through an encoder and compressing the features into global feature vectors through self-attention pooling; decoding the image into a temperature field image by adopting a U-Net generator fused with jump connection; a multi-scale discriminator is constructed, a semantic weighting mechanism is introduced, and differentiated weights are distributed to cooling holes, tenons and pressure surface areas; a physical constraint loss and local energy conservation loss are constructed based on a heat conduction equation, and a weighted training model is combined with confrontation loss and temperature error loss. The method is used for providing high-precision temperature distribution data support for turbine blade structure optimization design, cooling system efficiency evaluation and thermal fatigue prevention.

The invention discloses a self-correction optimization method and system for heat transfer boundary conditions of a water jacket heater, and particularly relates to the technical field of condition optimization control. The method comprises the following steps: constructing a thermal fatigue deformation trend estimation model by collecting a furnace wall surface temperature sequence, furnace wall surface heat flux distribution information and a furnace wall thermal stress response curve of a furnace body structure component, and generating a geometric parameter drift vector; performing structure equivalent mapping analysis on the geometric parameter drift vector, and extracting contact thermal resistance change information; performing furnace wall heat flow field reconstruction on the geometric parameter drift vector to obtain a dynamic correction vector; and the contact thermal resistance change information and the heat flow correction vector are comprehensively analyzed, a time-varying boundary condition inversion model is constructed, and a multi-parameter coupling boundary correction set is output and used for updating the boundary conditions in the water jacket heating furnace heat transfer simulation model, so that identification and self-adaptive correction of the boundary conditions are realized, and the heat transfer control precision and the heat efficiency are improved.

The invention relates to the technical field of digital twinning, and discloses a precision casting mold life prediction method based on digital twinning, which comprises a mold data acquisition module, a mold data processing module, a mold coefficient generation module, a prediction model establishment module and a mold life prediction module. Physical data, operation data and maintenance records are synchronously collected through the multi-source sensor, and full-life-cycle real-time monitoring is achieved; establishing comprehensive evaluation of four types of quantization coefficients, thermal fatigue coefficients, comprehensive mechanical coefficients, comprehensive wear coefficients and comprehensive maintenance coefficients to realize multi-field damage coupling analysis; the life prediction index unifies the multi-dimensional damage to be 0-1 standard, outputs a visual life percentage and sets a graded early warning threshold value, so that the prediction precision is improved; all coefficients are calculated through a standardized formula, a full-digital process from data acquisition to index generation to model prediction to decision support is constructed, and the detection requirements of new materials and complex structure molds are met.

The invention provides an LNG ship pipe fitting fatigue life modeling optimization method and system. The method comprises the steps that a fatigue life simulation model of a low-temperature pipe fitting is established; fatigue state constraint is applied to a fatigue damage structure in the fatigue life simulation model based on the load spectrum and the temperature spectrum at the monitoring node, and a damage constraint condition of the target low-temperature pipe fitting in a vibration state is obtained; determining the thermal fatigue loss of fatigue life simulation under different low-temperature thermal cycle loads according to the thermal fatigue damage and load spectrum characteristics of each connection part under different low-temperature thermal cycle loads; cost optimization is carried out on fatigue life control parameters of the fatigue life simulation model according to the damage constraint conditions and all the thermal fatigue losses, optimal cost parameters for fatigue life simulation under the thermal-vibration load working condition are obtained, and the local grid density of the fatigue life simulation model is adjusted based on the optimal cost parameters. By the adoption of the scheme, parameter cost optimization of the fatigue life simulation model of the LNG ship pipe fitting under the thermal-vibration load working condition can be achieved.

A system may comprise a neural network trained to predict mechanical damage to field-deployed industrial equipment with a main or supplementary function to transfer heat change phase, or drive / limit a reaction. The neural network may be trained using an idealized geometry. A processor may receive process input data from the equipment and may provide the data to the trained neural network. The processor may generate a prediction of mechanical damage using the trained neural network and the process input data. The process input data may comprise temperature data collected during operation. A scanning device may generate a digital twin of at least a portion of the equipment through scanning and ultrasonic testing. A monitoring module may monitor processes through a control system to collect the process input data. The neural network may comprise a convolutional neural network configured to calculate damage using a surrogate model.

The invention provides a thermal cycle period customized thermal fatigue test method and equipment, the equipment comprises a rotation system, a heating unit, a cooling unit, a temperature detection probe, a temperature detector and a temperature controller, the temperature controller outputs signals to control the rotation system and a temperature adjusting system, thermal and cold circulation of a workpiece is realized, and the thermal fatigue test efficiency is improved. The temperature value of the sample in the whole cycle period is obtained through signal input of the temperature detector, the temperature controller compares the temperature fed back by the temperature detector with the set temperature, then the rotating system, the cooling unit and the heating unit are regulated and controlled and optimized continuously, and fitting of temperature waveforms is achieved. According to the equipment, through cooperative work of the temperature controller, the temperature adjusting system, the temperature detector and the rotating system, temperature control and rotating control on the sample placing platform are realized, so that the thermal fatigue test requirements of the same test material under various working conditions are met.

The invention, which relates to the technical field of power transmission, discloses a high-power intelligent temperature control cable comprising a conductor, a first insulating layer, a temperature control system, an early warning system and a protective sleeve. The conductor is made of a high-conductivity material, and the conductor is coated with a first insulating layer; the temperature control system comprises a liquid cooling pipe and a plurality of temperature sensors, and cooling liquid is suitable for flowing in the liquid cooling pipe; the early warning system comprises a temperature sensing optical fiber which is distributed along the axial direction of the conductor, and the temperature sensing optical fiber is connected with a fault early warning module; the protection sleeve wraps the conductor, the temperature control system and the temperature sensing optical fiber and comprises an electromagnetic shielding layer, a mechanical protection layer and a safety protection layer. The temperature sensor and the fault early warning module are used for connecting the control unit. The operating temperature of the cable is adjusted in real time through the temperature control system, and thermal fatigue of the conductor is effectively inhibited; high-strength electromagnetic shielding, mechanical tensile strength and bending resistance are provided through the protective sleeve; and the temperature and strain states of the cable are monitored in real time through the early warning system, so that the operation safety is improved.

The invention discloses a high-frequency induction intelligent control system and a thermal fatigue test method, and belongs to the technical field of thermal fatigue tests.The method specifically comprises the steps that a to-be-tested sample piece is installed, heating parameters are set, heating is started, heating is stopped after the to-be-tested sample piece is heated to a preset temperature, and the to-be-tested sample piece is cooled until the temperature drops to a preset lower limit; in the heating and cooling process, the surface and core temperature of a to-be-detected sample piece is collected in real time, the heating-cooling step is repeatedly executed according to the preset number of cycles or to a preset damage threshold value, the temperature curve, the power curve and the cycle count of each cycle are generated, the recorded temperature curve, the power curve and the cycle count are analyzed, and the temperature of the to-be-detected sample piece is obtained. Outputting the thermal fatigue life value of the to-be-tested sample piece; the temperature is intelligently controlled through high-frequency induction, the uniformity of the temperature is ensured, the thermal fatigue life is accurately predicted through multi-dimensional life evaluation and layered modeling, and the speed, precision and reliability of thermal fatigue testing are remarkably improved.

The invention provides a thermal fatigue test system and method for testing thermal shock resistance of a stealth coating, and belongs to the technical field of aero-engine tests.The system comprises a switching section used for introducing main runner gas and measuring the state of the main runner gas; the exhaust section is used for exhausting gas in the main runner and cooling the gas; the test cascade comprises a test piece and a container device wrapping the test piece, the front end of the container device is connected with the switching section, the rear end of the container device is connected with the exhaust section, and the test piece is inserted into the container device; the cooling air system comprises a compressed air control system and an electric heater, the compressed air control system comprises a flowmeter, a three-way valve and an exhaust regulating valve, the flowmeter is arranged at the front end of the electric heater, the rear end of the electric heater is connected with an inlet of the three-way valve, one outlet of the three-way valve is connected to an inlet of the test piece, and the other outlet is connected with the exhaust regulating valve for exhausting; and the test and data acquisition system comprises a temperature measuring instrument, a pressure scanning valve and kingview software.

The invention relates to thermal fatigue resistant ceramic and a production process thereof, and belongs to the technical field of ceramic material preparation, the thermal fatigue resistant ceramic comprises the following raw materials by mass: 90-100 parts of a base material, 5-10 parts of a flexibilizer, 1-3 parts of a sintering aid and 1-3 parts of an additive; wherein the base material is obtained by mixing calcium carbonate, talc, aluminum oxide, kaolin and a nano zirconium oxide precursor according to the mass ratio of (0.75-1.25): (2-3): (80-85): (3-4): (3-4). The base material in the thermal fatigue-resistant ceramic selects the aluminum oxide as a main component, and the aluminum oxide has extremely high melting point and hardness and excellent chemical stability, so that the ceramic can keep stable physical and chemical properties in a high-temperature environment, and the thermal fatigue resistance of the ceramic is remarkably enhanced.

The invention discloses a heat dissipation substrate and a preparation method and application thereof, and belongs to the technical field of heat dissipation plates. The heat dissipation substrate comprises a first copper layer, a first brazing layer, a first TiC layer, a diamond sheet layer, a second TiC layer, a second brazing layer and a second copper layer which are sequentially arranged in a stacked mode. And a groove for placing a chip is formed in the surface of one side, far away from the diamond sheet layer, of the first copper layer. The heat dissipation substrate is good in heat conductivity, high in heat dissipation efficiency, small in thermal stress between the layers and good in binding force. The preparation method is simple in process, controllable in cost and suitable for industrial production. The vehicle-mounted SiC chip packaging heat dissipation plate comprising the heat dissipation substrate can efficiently dissipate heat under the working conditions of high heat flux, high temperature, high pressure and high frequency, and can effectively prevent the chip from beforehand failure caused by thermal stress and thermal fatigue, thereby ensuring higher reliability and longer service life; and the requirements of high-power and high-current-density new energy automobiles can be met.

A system may comprise a neural network trained to predict mechanical damage to field-deployed industrial equipment with a main or supplementary function to transfer heat change phase, or drive / limit a reaction. The neural network may be trained using an idealized geometry. A processor may receive process input data from the equipment and may provide the data to the trained neural network. The processor may generate a prediction of mechanical damage using the trained neural network and the process input data. The process input data may comprise temperature data collected during operation. A scanning device may generate a digital twin of at least a portion of the equipment through scanning and ultrasonic testing. A monitoring module may monitor processes through a control system to collect the process input data. The neural network may comprise a convolutional neural network configured to calculate damage using a surrogate model.

The invention discloses a high-strength photovoltaic welding flux for a photovoltaic welding strip and a preparation method of the high-strength photovoltaic welding flux, and belongs to the technical field of energy conservation and environmental protection. According to the solder, the Sn-Zn-Bi alloy is used as a matrix, and the performance is comprehensively improved by introducing a dual nano reinforced phase of the multi-walled carbon nanotubes and the nano nickel particles. The preparation method comprises the steps of matrix alloy melting, a hydrothermal method, a liquid phase reduction method, ultrasonic dispersion, gas atomization powder preparation, silane coupling agent surface modification, scaling powder compounding, reflow soldering and the like. The obtained solder has excellent comprehensive performance, excellent thermal fatigue resistance and long-term reliability. The welding flux is suitable for interconnection welding of a main grid, a fine grid and a welding strip of a crystalline silicon photovoltaic cell, and provides technical guarantee for the service life of a photovoltaic module more than 25 years.

The invention belongs to the field of artificial intelligence and energy power system cross control, and particularly relates to a coal-fired unit fused salt combined frequency modulation control method and device based on deep reinforcement learning. According to the method, a deep reinforcement learning agent model is constructed, and boiler fuel quantity, steam turbine valve position, fused salt heat charging and discharging power and pump starting and stopping signals are dynamically output based on state space vectors; and tracking precision, thermal stress, emission and coal consumption indexes are fused through a multi-target reward function, and strategy autonomous optimization is realized by adopting a double-Q network, experience playback and target network delay updating mechanism. After deployment, the boiler, the steam turbine and the molten salt unit can be coordinated on line, power space-time decoupling and closed-loop cooperation are achieved, on the premise that main steam parameter stability and equipment safety are guaranteed, the frequency modulation response speed and precision are remarkably improved, the thermal fatigue risk is reduced, and the unit economy and the power grid adaptability are enhanced. And a flexible adaptive adjustment capability is provided for a high-proportion new energy power system.

The invention discloses a material with a silver coating for low-temperature brazing of brazing filler metal, and particularly relates to the field of brazing welding, which comprises the following steps: silver amalgam paste is prepared by oscillating and mixing silver powder and mercury according to the mass ratio of 1: 9-0.5: 9.5 in a manner and method for plating silver on the surface of base metal (metal, semiconductor, ceramic or glass); when brazing is carried out, the surface of the silver plating layer of the to-be-welded piece is coated with brazing filler metal, and then heating and pressurizing are carried out in a low-temperature interval of 120-350 DEG C in a vacuum, protective atmosphere or atmospheric environment to complete connection. According to the method, the amalgam reaction and isothermal solidification principles are utilized, a tough welding spot mainly comprising a silver-based solid solution is finally formed, generation of a large number of brittle intermetallic compounds is avoided, a connector has high strength, high reliability and excellent thermal fatigue resistance, and therefore the problems that gold-tin brazing filler metal is high in cost, the brittleness of the welding spot is large, and the welding temperature is high are successfully solved.

The invention discloses an H13 steel mold intelligent temperature control and thermal fatigue prediction cooperation system and a use method thereof, and relates to the field of steel molds, the H13 steel mold intelligent temperature control and thermal fatigue prediction cooperation system comprises an intelligent temperature control subsystem, a thermal fatigue prediction subsystem, a data processing and storage module, a fault diagnosis module, a data interaction and cooperation module and a user management and authority module. According to the invention, the intelligent temperature control subsystem utilizes dual-controller redundancy and dynamic strategy adjustment to realize high-precision dynamic temperature control, the thermal fatigue prediction subsystem is fused with a multi-scale model and an LSTM neural network to realize high-precision prediction, and the data processing module supports efficient noise reduction and cross-domain data conversion. The fault diagnosis module constructs a multi-level threshold detection and intelligent response system, the data interaction module realizes multi-protocol compatibility and full-process collaboration, and the user management module ensures system safety and global adaptation, so that the temperature control precision, the thermal fatigue prediction reliability and the production collaboration efficiency of the mold are integrally improved, the maintenance cost is reduced, and the service life of the mold is prolonged.

The invention provides a preparation method and application of ceramic slurry for high-temperature bonding of aluminum nitride ceramics, and relates to the technical field of high-temperature ceramic materials.The preparation method comprises the following steps that firstly, an organic carrier is prepared, a polymer binder, an organic solvent, a plasticizer and a dispersing agent are weighed according to the weight ratio and stirred at the temperature of 60-70 DEG C till complete dissolution and clarification are achieved for use; 2, an inorganic functional phase is prepared, aluminum nitride powder, yttrium oxide powder and alkaline earth metal oxide powder are weighed according to the weight proportion and placed in a ball milling tank to be evenly mixed, the obtained ceramic slurry serves as a bonding layer, the tolerable temperature can reach 1000 DEG C or above and is far higher than that of metal brazing filler metal, and the ceramic slurry is suitable for severe environments such as aerospace and high-temperature sensors. The main components of the bonding layer are consistent with the base material, and the thermal expansion coefficient is highly matched, so that the thermal stress can be greatly relieved, and the failure of the device caused by thermal fatigue in the temperature cycle is avoided.

The invention discloses a thermal fatigue testing device for a turbine guide vane. The thermal fatigue testing device comprises a base; the heating module comprises a profiling wire of which the shape is matched with the cross section of the to-be-tested piece and a power supply for driving the profiling wire to generate an induction heating magnetic field through alternating current; the axis height of the annular track is aligned with that of the profiling wire, and the annular track surrounds the periphery of the profiling wire; at least one independent temperature control module, each independent temperature control module is movably arranged on the annular track, and the local temperature of the to-be-tested piece is controlled by adjusting the magnetic field intensity of the corresponding section on the profiling wire through magnetic shielding; and at least one temperature detection module, wherein each temperature detection module is used for collecting temperature distribution data in real time. Through multi-area independent temperature control, non-uniform temperature gradient loading of the front edge area, the middle section area and the tail edge area of the turbine guide blade is achieved, and the thermal stress field of the blade under the real engine working condition is accurately simulated.

The invention provides a cable accessory insulation aging evaluation method and system. The method comprises the following steps: determining internal degradation characteristic parameters of a target cable accessory through a micro-vibration signal of the target cable accessory in an excitation process; determining the degradation gradient of the target cable accessory under the hydrolytic aging effect according to the degradation characteristic parameters and the environment humidity of the target cable accessory, and determining the dielectric attenuation trend of insulation aging of the target cable accessory in the operation process based on the degradation gradient and the electric field characteristics of the target cable accessory; determining thermal fatigue accumulated loss of the temperature to the target cable accessory according to a coupling association relationship between all the monitored surface temperatures and the micro-vibration signal; and performing aging evaluation on the insulation state of the target cable accessory through the dielectric attenuation trend and the thermal fatigue accumulated loss to obtain an evaluation index of insulation aging of the target cable accessory. By adopting the scheme of the invention, the influence of internal microscopic degradation expansion on the evaluation of the insulation aging of the target cable accessory can be reduced.

The invention discloses a pipe die submerged arc surfacing remanufacturing method and system capable of improving the thermal fatigue performance, and the method comprises the following steps: 1, pretreatment: removing thermal fatigue cracks, cracks and wear scratches on the inner wall of a pipe die by adopting a turning or boring process, the method comprises the following steps of (1) pre-treating a pipe die, (2) pre-heating at low temperature: pre-heating a to-be-welded part of the pre-treated pipe die by adopting a high-frequency induction heating module, (3) carrying out submerged arc surfacing, (4) carrying out subarea induction tempering treatment on the surfaced pipe die, firstly turning or boring all thermal fatigue cracks, cracks, abrasion scratches and high-temperature oxidation fatigue layers on the inner wall of the pipe die, and then carrying out tempering treatment on the pipe die. A low-temperature preheating welding wire formula is adopted, crack resistance is achieved under low heat input, a good structure is formed, curved surface self-adaptive welding is achieved, powder is automatically added in the welding process, welding slag is automatically cleaned, dotting is conducted after welding, stress is released, and longitudinal or transverse cracks are effectively avoided. And tempering the pipe die repaired by surfacing after welding, and carrying out ultrasonic scanning and residual stress testing.

The invention discloses a die-casting die thermal fatigue life detection device, and relates to the technical field of die-casting die detection, the die-casting die thermal fatigue life detection device comprises a detection machine body and a control platform, and the top of the detection machine body is provided with a material thermal fatigue detection assembly and a mechanical load mechanism. When the device is used, the electric push rod pushes the heat insulation sleeve to penetrate through the penetrating hole and continue to move, and the movable turning cover is jacked upwards. Under the combination of the vacuum cavity, the honeycomb-shaped porous heat insulation plate and the metal foil reflecting screen, the heat insulation sleeve forms a triple barrier of reflection, vacuum and porous heat insulation, heat transfer is blocked, and it is guaranteed that cold air is not affected by heat of an air cooling opening when blown. When the material thermal fatigue detection assembly works, the cold air pipe and the heat insulation sleeve are located outside the detection box, the heat absorption temperature of the cold air pipe is prevented from increasing in the heating process, and the mold thermal fatigue detection precision and efficiency can be improved.

The embodiment of the invention provides a thermal fatigue life reliability evaluation method for a thermal interface material, and the method comprises the steps: applying a boundary condition and a temperature load to a thermal interface material simulation model, and appointing the physical quantity of the thermal interface material, which needs to be output by the thermal interface material simulation model, so as to enable the thermal interface material simulation model to carry out simulation; and determining the thermal fatigue life reliability of the thermal interface material in the preset temperature change range according to the simulation result. Through the embodiment of the invention, the problems of long time consumption and high cost caused by the fact that the thermal fatigue life reliability evaluation of the thermal interface material depends on the real reliability test after chip packaging in the related technology are solved.

The invention discloses a die-casting die material thermal fatigue testing device, which relates to the field of material performance testing, and comprises a shell, a support frame, a clamp, a first temperature measuring component, a die temperature controller, a molten metal heating device, a molten metal conveying mechanism, a molten metal spraying mechanism, a release agent spraying mechanism, a release agent supply mechanism and a control system, one end of the molten metal spraying mechanism is located in the shell, and the other end of the molten metal spraying mechanism is located outside the shell and connected with the molten metal heating device through the molten metal conveying mechanism. One end of the release agent spraying mechanism is located in the shell, and the other end of the release agent spraying mechanism is located outside the shell and connected with the release agent supply mechanism. The first temperature measuring component is arranged in a test piece, an outlet of the mold temperature controller is connected with an inlet of a runner in the test piece, and an inlet of the mold temperature controller is connected with an outlet of the runner in the test piece. The device solves the problems of temperature field distortion, insufficient multi-physical field coupling and low efficiency, and realizes high-precision and high-efficiency service life prediction and failure analysis of the die-casting die.

The invention relates to the technical field of numerical control machining centers, and provides a numerical control machining center protection method and system.The numerical control machining center protection method comprises the steps that vibration signals are collected and decomposed to obtain trend terms; a tool wear compensation factor is obtained based on the tool accumulated machining duration and the material removal amount, and compensation correction is conducted on the trend term according to the tool wear compensation factor; and obtaining a basic collision risk probability according to the compensated and corrected trend term. According to the method, the baseline offset of the vibration signal can be compensated and corrected in real time based on the accumulated machining time length of the cutter and the material removal amount, the time accumulation (thermal fatigue effect) and the cutting load (mechanical wear) of the cutter can be responded at the same time, the accuracy of basic collision risk probability calculation is improved, and safety protection of the numerical control machining center can be better achieved.

The invention relates to a regulation and control method for a nitridation permeable layer of a die-casting die. The regulation and control method comprises the following steps that the die-casting die is pretreated and partitioned; the pretreated mold is placed in nitriding equipment, nitrogen and hydrogen are introduced into the nitriding equipment, the volume ratio of the nitrogen to the hydrogen is (4-5): 1, and heat preservation is conducted after the temperature in the nitriding equipment is increased to a first temperature interval; the nitriding reaction rate in the nitriding equipment is monitored and calculated in real time, and according to the subareas of the die-casting die, a subarea heating program is started, and different areas of the die-casting die are subjected to subarea heating; adjusting the volume ratio of the nitrogen to the hydrogen to be 1: 1, maintaining the temperature of each zone set by the zone heating program, and maintaining the process parameters of the stage until the thickness and hardness of the nitride layer reach target values; and after the nitriding treatment is finished, the mold is cooled to the tapping temperature under the protective atmosphere. The hardness distribution uniformity, the thermal fatigue resistance, the wear resistance and the overall service life of the die-casting die can be improved.

The invention discloses an underfill thermal fatigue analysis system based on analog simulation, and relates to the technical field of chip processing, the underfill thermal fatigue analysis system comprises a data acquisition unit, a simulation modeling unit, a thermal cycle loading unit, a damage calculation unit and a result output unit; according to the method, the basic data, the thermal fatigue influence factors and the thermal fatigue damage judgment data of the underfill are obtained, and the thermal fatigue analysis model of the underfill is constructed on the basis of an analog simulation principle, so that the relationship between the thermal fatigue influence factors of the underfill and the thermal fatigue damage degree is analyzed. And residual stress distribution in the thermal cycle process is calculated based on a thermal-mechanical coupling algorithm, and local refinement analysis is performed on a high stress gradient region through a sub-model technology to obtain thermal fatigue feedback data. And performing fatigue life prediction on the three-dimensional finite element model subjected to thermal cycle loading by adopting an accumulative damage theory, generating a stress-strain curve and a damage evolution cloud chart, and displaying a thermal fatigue analysis result in a visual form.

The invention belongs to the technical field of ferrous metallurgy and material modification, and particularly relates to a preparation method of green short-process hot work die steel, which comprises the following steps: obtaining scrap steel, adding alloy, and smelting to obtain molten steel; the molten steel is refined through fluoride-free rare earth refining slag, and refined molten steel is obtained; adding a nanoparticle modifier into the refined molten steel to obtain modified molten steel; and the modified molten steel is subjected to continuous casting or die casting, and the hot work die steel is obtained. According to the method, the fluorine-free rare earth slag refining and nano particle modification combined technology is adopted, fluorine-containing refining slag and traditional electroslag remelting are effectively replaced, power consumption and carbon emission in the smelting process are reduced, the technical development requirements of current green manufacturing and dual-carbon targets are met, and green short-process manufacturing of the hot work die steel is achieved; and the prepared hot work die steel has higher cleanliness, a more uniform organization structure and more excellent thermal fatigue performance.

The invention provides an engine cylinder cover thermal fatigue virtual test verification method and system, and relates to the technical field of virtual simulation modeling, and the method comprises the steps: obtaining the micro-macro parameter characteristics of an engine cylinder cover; constructing a parameterized model of micro-macro coupling; performing reverse solution on the control parameters of the physical rack based on a target temperature circulation curve set by a user to obtain a boundary condition parameter set required by a virtual test; generating a virtual-real homologous file according to the parameterized model and the boundary condition parameter set; actual measurement temperature data after the physical rack executes the control instruction file and simulation temperature data after the finite element analysis software executes the simulation input file are collected; according to the two-dimensional topological structure of the fire power surface, virtual thermocouple measuring point coordinates are generated; establishing data channel mapping according to the measuring point coordinates of the virtual thermocouple; calculating temperature errors of the plurality of measuring points; when the temperature error exceeds a threshold value, a correction prompt for the measuring point is output; and verifying the parameterized model according to the correction prompt.

The invention relates to the technical field of metal material surface engineering and equipment remanufacturing, in particular to an early acoustic emission diagnosis and laser cladding repair method for thermal fatigue cracks in a mold service process, which comprises the following steps: S1, synchronously acquiring and preprocessing multi-source heterogeneous data; stress wave signals are collected in real time through a broadband acoustic emission sensor array permanently integrated on the surface of a mold cavity, the frequency response range of the sensor is 100 kHz to 1 MHz, and the sensitivity is not lower than 95 dB. According to the method, accurate identification and positioning can be realized at the initial stage of crack initiation through multi-modal sensing fusion and a deep learning algorithm, the diagnosis accuracy is remarkably higher than that of a traditional offline detection method, and precious time is won for subsequent repair.