The high parameter operation of the magnetic confinement fusion device requires a good vacuum environment, and the divertor is the core component of the Tokamak device. The divertors have two operating conditions of high temperature nitrogen baking and water cooling, and there is a great risk of leakage, so the leak detection of the divertor component is very important. In this paper, a set of baking leak detection system is set up to meet the air tightness testing requirements of the lower EAST divertor, which can simulate the high temperature and normal temperature environment of the divertor during operation, and test the air tightness of the internal flow channel of the divertor. The as-built air tightness detection system can bake at a maximum temperature of 600 ℃, and the ultimate vacuum can reach 5×10^-5 Pa, which can meet the air tightness detection requirements of the lower divertor of EAST under normal temperature and baking at 200 ℃. The measurement error caused by time accumulation of standard leakage is optimized by adding small vacuum chamber. Under normal and high temperature conditions, the minimum detectable leak rate of the system meets the requirements of the positive pressure baking gas tightness testing of the lower divertor, but the background reading of leak detector of the system at high temperature is 1 to 2 orders of magnitude higher than that at normal temperature. This is caused by the release of water vapor and hydrogen under high temperature condition, which can be solved by extending the baking and holding time.

To enhance the operational reliability of integrated vacuum interrupter devices under extreme conditions, a real-time process automation （RPA） control engine based on multi-parameter feedback and a composite arc-extinguishing strategy combining magnetic blowing and pulsed airflow is proposed. A closed-loop feedback mechanism is established by constructing a dynamic vacuum threshold classification model, a Kalman filter-based leakage rate compensation algorithm, and a spectral inversion method for contact ablation. A dual-mode cooperative control architecture combining fuzzy PID and deep reinforcement learning ensures millisecond-level precision in opening and closing operations. Coupled with magnetic field gradient focusing and timed airflow matching, a multi-path energy dissipation model for arc plasma is formed. Experimental results show that the vacuum fluctuation range is reduced from ±12.3% to ±4.2%, the arc re-ignition probability drops from 1.5% to 0.3%, and the dielectric recovery strength increases by 27.6%. This study provides theoretical and technical support for the intelligent upgrading of vacuum interrupter devices and is applicable to circuit breaker performance optimization in scenarios such as renewable energy integration and DC distribution networks.

To investigate the sealing performance of a 60° cone seal structure under 1 200 MPa high-pressure condition, simulation analysis was conducted using ANSYS Workbench software to obtain the contact pressure distribution on the sealing surface. Sealing performance experiments were then carried out under a 1 200 MPa oil medium load using different material combinations. The experiment employed a “soft-hard” material combination of 316L and Cr12MoV, with varying tightening torques to test the sealing effect. The results show that this material combination maintains excellent sealing performance and no leakage under ultra-high pressure. A tightening torque greater than 180 N·m is required for stable sealing, and the difference in material hardness plays a significant role in enhancing sealing reliability and service life. This structure demonstrates good application potential in high-pressure environments and is suitable for critical equipment requiring ultra-high pressure sealing.

This article focuses on the possible electromagnetic compatibility issues of the electron beam magnetic field control power supply in complex electromagnetic environments accompanied by electron gun firing conditions. The signal of magnetic field control power supply is collected based on FPGA technology. A simulation test platform was built to determine the typical forms of interference sources that affect the magnetic field control power supply, and the strength and frequency range of interference sources were tested. The filtering circuits in output terminal and control circuit of magnetic field control power supply were designed to suppress external environmental interference. By using MOSFET and resistor series parallel combination for transient voltage division, the ignition energy of the electron gun is instantly absorbed. The optimized electron beam trajectory control system can enhance the electromagnetic compatibility of the system.

Accurate measurement of volume coefficient is the key for pressure leaks calibration by volume compensation pressure leak calibration device. In order to improve the measurement accuracy of the volume coefficient, the relationship between volume coefficient and differential pressure in two cases of without and with leaks was studied, and the consistency of volume coefficient of the same adjustable leak under different leak rates was tested in this paper. The volume coefficient was corrected by making simulation joints and correcting ΔP based on theoretical analysis of test results. Finally, the volume coefficient stability of the fixed value leak was tested. The results show that the accuracy and stability of the corrected volume coefficient test are significantly improved, and the test consistency of the two correction methods is less than 0.2%, and the stability is less than 0.5%.

A kind of linear profile rotor screw vacuum pump was proposed , and the main structural parameters of the rotor profile of the LG70 screw vacuum pump were given. The new screw pump processing method was analyzed and improved. Based on the rotor profile, the actual product production was carried out, and the pumping speed and other performance indexes were compared with the original cycloidal rotor screw pump. The results show that the new design is characterized by high volume efficiency, convenient processing and accurate positioning, and the efficiency of production and pumping of the linear rotor screw pump are improved compared with the cycloidal rotor screw pump.

The pre-stressed wound steel wires are widely used in the pressure bearing vessel part of equipment such as hot isostatic pressing. Firstly, the numerical model of variable tension vessel winding and the model of equal-tension step division were established. Then, step division method was optimized by using the numerical analysis software and algorithms, and the optimal solution for saving the number of steel wire weights under the precondition of meeting the bearing capacity was obtained. Finally, by establishing a winding simulation model of the container, the correctness of the results was verified by using the finite element analysis software.

At present, the temperature for preparing ytterbium by lanthanum thermal reduction method in industry is usually set at 1 200 ℃, the yield and purity of ytterbium are high, but the reaction is intense. In view of the fact that some specific engineering fields have strict requirements for atomic vapour density of the reaction product, this article analyses the process and thermodynamics of lanthanum thermal reduction to prepare ytterbium with high purity ytterbium oxide and lanthanum chips as raw materials. The influence of reduction temperature and reducing agent ratio on atomic vapour density were studied. The results show that there is a slight reaction at 650 ℃. At 700-800 ℃, the atomic vapour density increases dramatically with the temperature. The atomic vapour density is above 10¹² cm^-3 over 800 ℃. At 850-1 000 ℃, the purity of the reaction product is not less than 99.79%, when the excess ratio of reducing agent is lower than 100 %, the ytterbium atom vapour density still increases significantly with the increase of reaction temperature.

The vacuum sintering furnace is a crucial apparatus for the growth of silicon carbide, where the temperature uniformity within the furnace serves as a key performance indicator, directly impacting the quality of the workpieces. In this paper, numerical simulations on the temperature field inside a vacuum sintering furnace was conducted to investigate the influence of graphite-plate thickness on temperature uniformity. The results indicate that the thickness of the lower support plate has the most significant effect on furnace temperature uniformity, followed by the cover plate, while the side plate exerts a negligible role. The optimized thicknesses of the lower, cover and side plates are 50, 20 and 60 mm, respectively, the maximum temperature difference within workpieces thus decreased by 19.1 ℃ i.e., 10.7%. This study may provide valuable insights for the design and optimization of graphite plate of vacuum sintering furnace.

In response to the demand for green and low-carbon development in steel industry, advancing dual vacuum melting (VIM+VAR) towards low-carbon production has become a new research direction. This paper investigates the law of change on carbon and oxygen content in special steel during the vacuum melting process using iron-based materials manufactured by electric arc furnace and electrolytic iron as raw materials, conducts kinetic studies of denitrification on high chromium (Cr) alloy steel. By controlling vacuum deoxidation, denitrification, and desulfurization, it can achieve low-carbon dual vacuum special steels with high purity by different process. The results show that the preparation process of double vacuum special steel can significantly reduce carbon emissions and promote the green and low-carbon development of double vacuum special steel. The vacuum carbon deoxidation effect of high-carbon steel represented by M50 is obvious, which can achieve the control of low-oxygen fine inclusions.

BT22 (Ti-5Al-5Mo-5V-1Cr-1Fe) alloy is widely used in the aerospace field because of its good strength, toughness and hardenability. Addressing the problems of crucible contamination and composition segregation present in traditional titanium alloy melting methods, BT22 alloy was prepared using a self-developed vacuum induction magnetic levitation melting furnace. The microstructure and mechanical properties of as-cast and HIP alloys were compared and analyzed. The results show that: the BT22 alloy prepared by vacuum induction magnetic levitation melting method has a uniform composition, and the as cast and hot isostatic pressing microstructures are typical Weinstein structures. After hot isostatic pressing, the β-Ti grains grow, and at the same time, the fine acicular α phases inside the grain and at the grain boundaries increase. At room temperature, the tensile strength of as cast BT22 alloy reaches 1 293 MPa±3 MPa, with the elongation of only 1%±0.5%. After hot isostatic pressing, it exhibits good comprehensive mechanical properties, with roomtemperature tensile strength of 1 067 MPa±1 MPa and the elongation of 10%±1%.

With the booming development of the new energy vehicle market, lithium-ion battery serves as the core power source, its performance improvement has become the key point. The application of vacuum distillation furnaces in the new cathode materials for lithium-ion batteries demonstrates significant advantages. By analyzing the challenges faced by lithium-ion battery cathode materials, the technical principles and benefits of vacuum distillation furnaces are expounded, covering key technologies such as high-temperature evaporation systems, temperature control in the transition zone, rotary cooling constant-temperature collection system, and vacuum maintenance system. The results show that vacuum distillation furnaces can efficiently produce high-quality silicon monoxide (SiO) cathode materials, significantly enhance the material performance consistency and boost the energy density of lithium-ion batteries. Moreover, the furnace has the potential for large-scale production, which can reduce production costs and meet the market demand for high-performance lithium-ion batteries in new energy vehicles.

Flexible thermal control coating is the key for controlling the surface thermal balance of spacecraft. During the vacuum magnetron sputtering preparation process, various coating defects often occur due to real-time process fluctuations of the equipment. The traditional manual defect detection methods have the problems of relying on manual experience, low efficiency, high labor intensity, low accuracy, and poor real-time performance. To ensure the quality and efficiency of coating production, a coating defect detection model based on efficient adaptive convolution and channel space pyramid pooling was proposed, and the optimization design method of each key module was introduced in detail. The results show that this model can autonomously learn and model multi-layer representations of potential distributions, and extract features of the detected targets layer by layer through deep neural networks. The average recognition accuracy for 8 types of defects reaches about 93%, and the recognition speed FPS increases to 140. This method can effectively improve the quality of product production and meet the demand for efficient mass production.

To improve the adhesion between the chromium film layer of the mask substrate and the glass substrate, three layers of chromium film were fabricated on the Q6025 quartz glass substrate by magnetron sputtering. Two adhesion monitoring methods were used to study the effects of substrate temperature, sputtering atmosphere and annealing treatment on the adhesion of chromium film layer and substrate, while SEM was utilized to characterize and analyze the microstructure of the chromium film layers sputtered under different glass substrate heating temperatures and mixed atmospheres. The results show that heating the glass substrate to 160 ℃ leads to a better adhesion between the chromium film layer and the glass substrate. In addition, the microstructure of the chromium film layer produced in the mixed atmosphere consists of 50-60 nm pure chromium particles and 10-20 nm chromium oxynitride particles, which enhances the adhesion between the chromium film layer and the glass substrate. The annealing temperature of 300 ℃ and the holding time of 1 h further optimize the adhesion between the chromium film and the glass substrate.

The application effect of vacuum assisted technology in steel-concrete arch bridges was studied. Based on the construction parameters of a vacuum assisted steel-concrete arch bridge in a certain project, a comprehensive evaluation of the natural frequency, mode shape, and seismic response of the arch bridge was conducted using finite element analysis and experimental testing. The results show that the rise-span ratio and inclination angle of the arch bridge are positively correlated with the natural frequency. The amplification rates under the conditions of rise-span ratio of 1/5 and inclination angle of 14° are approximately 6.6% and 38.5%, respectively. Under the action of seismic waves, the response of arch bridges in the X direction is more obvious. In seismic design, more attention shall be paid to the seismic performance in the X direction. In the construction of vacuum assisted steel-concrete arch bridges, the rise-span ratio should be appropriately reduced and the inclination angle should be adjusted to optimize the structural stiffness of the arch bridge.

Aligning with the development trends of vacuum equipment, the advancement direction for air-cooled heat exchange systems is identified as enhancing heat transfer efficiency and incorporating sediment discharge functionality. This study optimizes the structure of the inlet air duct and the connecting duct between the heat exchanger and the fan through simulation calculations. Flow control calculations were performed to assess the impact of different duct structures on the outlet airflow of the air-cooled heat exchange system, with comparative analyses conducted on parameters such as duct outer wall temperature and outlet air velocity. The results indicate that compared to the traditional right-angle bend, the inlet duct employing a welded elbow and a split-type water-cooled jacket design exhibits increased outlet gas velocity and improved uniformity in wall temperature distribution. Introducing a reduced-diameter (DN100) sediment discharge port with a diversion structure into the connecting duct facilitates pollutant deposition, resulting in more stable gas velocity compared to the structure with an equal-diameter opening. Validation results demonstrate that this novel duct design can reduce pressure drop, decrease flow resistance, and significantly improve heat exchange efficiency.