The outgassing behavior of materials under vacuum environments represents one of the primary gas sources in high and ultra-high vacuum systems, significantly affecting the time required to achieve vacuum, the ultimate pressure, and the composition of residual gases in vacuum chambers. The performance of a vacuum system is closely related to the outgassing properties of the materials used, which in turn depend on a variety of factors including material type, production processes, surface conditions, microstructure, and external environmental factors. This review summarizes the outgassing mechanisms, influencing factors, and measurement techniques of materials in vacuum, discusses the effects of surface modification technologies-widely used in vacuum devices-on material outgassing behavior, and investigates the underlying mechanisms involved. Furthermore, this paper explores changes in material outgassing behavior and the corresponding mechanisms under the influence of physical fields such as high-energy particle irradiation, mechanical stress, and electric fields, thereby providing a theoretical basis and technical reference for the optimized design and engineering application of vacuum equipment.

The sputter ion pump (SIP) is a vacuum device widely used in ultra-high and extreme-high vacuum environments due to its simple structure, long service life, oil-free operation, and vibration-free, noiseless performance. Embedding non-evaporable getter (NEG) materials into the SIP core is an effective approach to enhance its ultimate vacuum level. In this study, a novel embedded structure was developed using direct current magnetron sputtering with dual coaxial cylindrical ring magnet targets to deposit NEG thin films on the inner wall of the SIP chamber. This configuration not only reduces outgassing from the chamber wall but also enhances the adsorption of active gases, thereby improving the ultimate vacuum performance of SIP. A Ti-Zr-V alloy with a fixed composition was selected as the NEG material. The study focuses on the uniformity of film thickness, investigating the effects of working pressure and sputtering power on both lateral and vertical uniformity of the films. Results show that increasing working pressure and sputtering power improves the uniformity, with a more pronounced effect in the vertical direction. Moreover, the ratio between target-substrate distance (D) and substrate width (W), defined as β, significantly influences the uniformity of the deposited film.

The application of vacuum continuous evaporation plating technology in the composite current collector industry remains constrained primarily by the service life limitations of the core evaporation component (ceramic evaporation boats). This study systematically investigates the corrosion process of evaporation boats used for composite current collectors. Micro-zone compositional and structural evolutions during corrosion are characterized via the X-ray diffraction and scanning electron microscopy. Compositional analyses of distinct corroded regions on the evaporation boat surface reveal that the failure mechanism of TiB₂-BN ceramic evaporation boats involves: (1) depletion of surface BN constituents, with aluminum nitride (AlN) identified as the primary corrosion product; (2) Layered flaky exfoliation of TiB₂ particles, which accumulate at the boat edges. As a conductive phase, TiB₂ induces localized resistance reduction, thereby enhancing current density and heat accumulation, ultimately triggering aluminum melt splashing. These findings may provide critical insights into material degradation mechanisms for optimizing evaporation boat design in composite current collector manufacturing.

Aiming at the problems of low control accuracy and slow response of the transmission system caused by torsional vibration of the transmission chain and magnetic circuit interference in vacuum magnetron sputtering coating equipment, the optimization transmission control technology of PVD coating vacuum magnetron sputtering coating equipment was studied. Based on the vacuum magnetic control area, the vibration transmission target was clarified, which was used as a guide to install damping shock absorbers to suppress external interference and achieve torsional vibration isolation of the transmission chain. In an isolated state, an integrated transmission method is adopted to achieve virtual damping transmission integration by adding an armature to counteract magnetic resistance and establishing scheduling associations on the transmission chain. Adopting a cross closed loop approach, collaborative processing is carried out in the order of transmission integration to achieve the final control task. The experimental results show that the transmission control delay of the coating equipment obtained by the proposed method is basically kept below 0.5 s, and the positioning accuracy of repeated transmission control is improved to 97%, which reflects the enhancement of the transmission control effect and highlights its superior performance.

The thermal screen has a direct impact on the insulation efficiency and temperature uniformity of vacuum furnace, determining energy consumption and workpiece quality. This article summarizes the types, physical properties and physicochemical properties of thermal screen materials and enhanced coatings. Then, four basic structures of thermal screens were sorted out, and their applicable conditions were analyzed. Finally, the influencing factors and evaluation indicators of thermal insulation effects were summarized. To meet the high insulation and precise temperature control requirements for vacuum furnace, future efforts should be dedicated to the modular, regional and integrated design of novel metal-nonmetal composite thermal shields, aiming to achieve online intelligent monitoring and control of thermal screens under various operating conditions for different types of furnace.

This study systematically investigates the effects of vacuum sintering on the sintering behavior, microstructure, and mechanical properties of Si-Ca system steel slag ceramic materials. By comparing the bulk density, water absorption, flexural strength, and microstructural evolution of materials sintered under vacuum and atmospheric conditions, the influence of vacuum environment on the ceramic sintering process was explored. The results indicate that vacuum sintering significantly increases the bulk density and reduces the water absorption of the ceramic materials. The optimal sintering temperature can be reduced by 20℃, while the flexural strength is improved by 10%~12%. Microstructural analysis shows that the vacuum environment promotes the oriented growth and optimized distribution of crystalline phases, resulting in a denser and more homogeneous microstructure. This study provides an effective processing route for low-temperature, high-performance sintering of industrial solid waste-based ceramic materials, and offers valuable reference for advancing solid waste resource utilization and energy-efficient manufacturing technologies.

Large vacuum induction furnaces are the core primary equipment for high-temperature alloy production. In the past few decades, this high-end equipment has been basically monopolized by internationally renowned enterprises such as the United States and Germany. Faced with a complex international situation, it is necessary for China to achieve domestic substitution in the field of large vacuum induction furnaces. This article takes large-scale vacuum induction furnaces as the research object, and first analyze the macro architecture characteristics of several mainstream large-scale vacuum induction furnaces abroad in depth; Then, several mainstream foreign large-scale vacuum induction furnace product architectures are introduced separately; Finally, based on the absorption of advanced foreign experience, a new architecture for large-scale vacuum induction furnaces that can meet the 3-30 t scale is proposed.

A non-contact volume measurement with gas calibration was proposed based on spacecraft helium mass spectrometry leak detection technology, and the mathematical model for volume measurement was established. The relationship between the test object volume and fitted slope of the gas calibration data was investigated by theoretical analysis and experimental studies. The results show that the fitted slope of gas calibration test data increases linearly with the increase of the object volume, using a rectangular sealed container with volume of 27 cubic meters as the platform, and the experimental studies indicate that the test object volume should not exceed 50% of the container volume. Simultaneously, the influence of container volume on the rate of gas calibration test data change was studied, and the experimental results show that a power function relationship exists between the container volume and the gas calibration data change rate. The measurement accuracy of the test object increases as the container volume decrease, and the optimal range for the rate of change in gas calibration data was determined to be on the order 10^-8 s^-1. This work also outlines the future research direction on non-contact volume measurement with the gas calibration method.

To ensure the long-term stable operation of vacuum medical systems, regular leak detection is required. To address the limitations of traditional leak detection methods that require shutdown and exhibit low efficiency, this study proposes an integrated ultrasonic leak detection and vacuum-driven self-impregnation in-situ repairing technology based on deep learning, which can quickly identify micro-leaks and seal them in place, thus ensuring the continuous operation of the systems. The method employs high-sensitivity piezoelectric sensors to capture structural acoustic signals in a negative pressure environment. A CNN-LSTM deep learning model is used to automatically extract spatiotemporal features, enabling high-precision identification and localization of micron-scale leak points. Subsequently, the vacuum pressure difference drives a low-viscosity sealant to form a forced viscous flow, achieving deep impregnation and solidified sealing of the leakage channels. Experimental results show that the as-proposed system achieves an average diagnostic accuracy of 97.1% under complex noise conditions. After repairing, the system vacuum is stably restored to 86.7 kPa, and the leakage rate decreases by more than 90%, significantly reducing the pump cycling frequency and energy consumption. This research realizes efficient online diagnosis and repair of medical vacuum systems without shutdown, providing a practical and extensible technical approach for intelligent maintenance of vacuum engineering equipment.

The simulation and structural optimization process of arc extinguishing chambers are mostly studied in isolation, considering electric or force fields, which makes it difficult to accurately characterize the dynamic behavior of arc extinguishing chambers under the coupling of multiple physical fields, resulting in poor performance of arc extinguishing chamber breaking. To this end, a multiphysics simulation and design of vacuum circuit breaker arc extinguishing chamber for smart grid was proposed. Constructed an electric field model based on Maxwell's equations, analyzed the relationship between charge and electric potential using Gaussian electric field law, and considered the induced electric field in dynamic processes using Faraday's electromagnetic induction law. Calculated electromagnetic force based on Ampere's Law, constructed an output field model, and then established a coupling relationship equation between electric field and force field parameters. A transient simulation model for bidirectional coupling of power has been established, surpassing the limitations of traditional single physical field analysis. To accurately evaluate the performance of the arc extinguishing chamber, a quantitative index of electric field uniformity and electromagnetic force stability were proposed for the first time. The commutation circuit parameter group of the circuit breaker was set as the optimization variable, and the electric field uniformity was quantified by combining the electric field strength. Then, the electromagnetic force stability was quantified by calculating the average electromagnetic force, and a multi-objective optimization function was constructed by minimizing mechanical stress. Implementing inductance and capacitance constraints, and combining non-dominated sorting particle swarm optimization (NSPSO) algorithm for collaborative optimization, using non-dominated sorting operation to update and iterate the parameter group of the converter circuit, and finally outputting the optimal structural parameter scheme for the vacuum circuit breaker arc extinguishing chamber. The results show that after simulating and optimizing the design of the arc extinguishing chamber using the proposed method, the contact wear is about 0.6 mm, which has ideal breaking performance and significantly improves the electrical life and operational reliability of the arc extinguishing chamber under short-circuit breaking conditions.

To address the problem of strong electromagnetic interference sources caused by transient field coupling on the electromagnetic compatibility of vacuum circuit breakers and improve their anti electromagnetic interference capabilities, this study proposes an electromagnetic compatibility optimization method for vacuum circuit breakers under transient field coupling. This method incorporates electromagnetic torque into the failure rate model under transient field coupling analysis, and determines the mean time between failures of vacuum circuit breakers as a compatibility failure indicator; based on the operating parameters of the shielding cover and contacts inside the vacuum arc extinguishing chamber, determine the electromagnetic compatibility optimization objectives, and combine improved deep learning to achieve multi parameter collaborative optimization of electromagnetic compatibility for vacuum circuit breakers. The results showed that the optimized electric field distribution uniformity was improved to 5.1%~6.6%, effectively avoiding magnetic field coupling under sudden changes in electromagnetic torque; Effectively suppress the intensity of electromagnetic field interference, with a minimum value of 3.66 mT and a maximum value of 7.25 mT.

To address the high-precision defect detection requirements of fasteners in vacuum equipment used in aerospace and nuclear power systems, this study evaluates the adaptability of ZnSe infrared window materials in terms of thermal stability, optical performance, and outgassing control. A correlation model between material properties and defect-recognition performance was established by integrating optical analysis in the 8-12 μm band with thermodynamic and vacuum-outgassing modeling, thereby quantifying the factors affecting imaging quality. A vacuum experimental platform was developed to simulate thermal cycling, particle impacts, and long-term outgassing conditions, and the performance of ZnSe was compared with that of Ge and AMTIR-1 materials. The results show that ZnSe exhibits a vacuum transmittance of 75%, a signal-to-noise ratio (SNR) of 45-50 dB, and an edge sharpness of ≤3 pixels. The defect-recognition accuracy reached 93-95%, with false-detection and missed-detection rates of ≤3% and ≤2%, respectively. After 500 hours of operation and 100 thermal cycles, the transmittance decreased by only 0.8%, with no cracking observed, and the outgassing rate remained ≤5×10^-9 Pa·L/(s·cm²), ensuring excellent sealing stability. These results demonstrate that ZnSe possesses superior vacuum infrared imaging performance and environmental adaptability, making it well suited for composite robotic thermal-imaging recognition systems and providing essential material support for high-vacuum inspection equipment.

To address the electron beam welding process requirements for complex workpieces in the nuclear industry, this paper proposes a design scheme for a local vacuum electron beam welding machine. It elaborates in detail the overall structural design framework of the equipment and constructs a local vacuum system composed of a main chamber (welding chamber), an auxiliary chamber, an electron gun chamber, and a transition chamber. Regarding the sealing structure, an innovative "positive-negative pressure synergistic drive" inflatable sealing system was proposed. By combining positive pressure inside the airbag with negative pressure outside, the contact pressure at the sealing interface was significantly enhanced. This was further integrated with a dual-airbag series arrangement and a vacuum barrier mechanism in the transition chamber, forming a multi-protection sealing structure that effectively addressed the challenge of maintaining a high vacuum in the local vacuum chamber under dynamic operating conditions. Experimental results showed that the vacuum level and the time to reach it for each vacuum chamber meet the design specifications. The effectiveness of the local vacuum technology is further verified through testing key indicators such as operating vacuum, ultimate vacuum, and pressure rise rate. The proposed positive-negative pressure synergistic sealing structure and the collaborative operation mode of the main and auxiliary chambers provide an engineering-applicable solution for local vacuum electron beam welding of complex workpieces, such as those with long dimensions and open ends, in the nuclear industry.

Aiming at the problem of insulation performance degradation caused by vacuum maintenance failure of vacuum insulation panels (VIP) in the field of building energy conservation under long-term service, this paper investigated in-situ monitoring of vacuum maintenance status for VIP and dynamic control of building energy conservation. Built a multimodal vacuum status monitoring platform to real-time collect key parameters of VIP core material vacuum maintenance status in situ; combining the improved particle filter algorithm, a vacuum attenuation dynamic model was constructed to dynamically predict the degradation trajectory of VIP's vacuum maintenance ability under different harsh climate conditions; developed a dynamic optimization system for building envelope structures based on deep reinforcement learning, coupled with BIM models and real-time vacuum monitoring data, to adaptively adjust the operating parameters of the building energy management system.The result shows that the research realizes the in-situ, continuous and accurate monitoring of the key parameters of VIP vacuum maintenance state in service. The vacuum decay prediction model provides a new method for evaluating the long-term service reliability of VIP. The optimization system based on real-time perception of vacuum state can effectively compensate the adiabatic loss caused by vacuum attenuation and significantly reduce building energy consumption.

The dynamic coupling effect of medium pressure pulsation and valve plate opening in vacuum systems seriously threatens the vacuum sealing integrity of the system, exacerbates the uneven stress distribution and deformation of the valve body, and thereby affects the instability load of the valve body. Therefore, the critical load of dynamic instability of the newly made three eccentric vacuum butterfly valve body is analyzed under the action of fluid medium. Based on the ANSYS Workbench platform, a three-dimensional parametric model is established to perform bidirectional fluid structure coupling (FSI) calculations between the unsteady flow of vacuum/low-pressure fluid medium (150℃ water vapor, Knudsen number 0.003-0.1, slip flow zone) and the valve body structure. In the fluid domain, the k-ω SST turbulence model is used to accurately simulate complex flow characteristics and calculate the distribution of fluid forces. In the structural domain, geometric nonlinear buckling analysis is performed based on the arc length method to accurately capture the instability behavior of the valve body under fluid forces, draw displacement load curves, and determine the critical load of instability under the dynamic coupling of medium pressure pulsation and valve plate opening. The results show that, under the dynamic coupling condition of 300 Hz medium pressure pulsation and valve plate 90° opening, the critical load for dynamic instability of the valve body is the worst, only 3×10³ Pa, and the risk of instability is the highest, which can easily lead to seal failure and vacuum degree damage.