In this paper, it shows firstly that the Pulsed-RF-GDOES (Pulsed-Radio-Frequency-Glow Discharge Optical Emission Spectrometry) depth profiling could reach one nanometer depth resolution as demonstrated by measuring the native SiO₂ layer thickness on the Si(111) substrate. A flexible optical functional film contained an Ag sublayer was characterized by atomic force microscope and spectrophotometer. Finally, the as-measured Ag Pulsed-RF-GDOES depth profiles were evaluated quantitatively using the MRI (atomic Mixing-Roughness-Information depth) model so that the depth resolution values are obtained with different measuring conditions. To this end, the optimum working conditions of the Pulsed-RF-GDOES are determined accordingly. The current study provides a useful guidance for obtaining high resolution depth profile for the flexible functional films.

Negative hydrogen ions sources are the preferred ions sources of the neutral beam injection system for the fusion apparatus, in which perfect negative hydrogen ion surface conversion material is the key problem. Diamond films have perfect secondary electron emission properties because of its negative electron affinity. In this article, the structures, working process and modes of H^- ions sources are introduced. The theory of secondary electron emission of diamond films and methods for enhancing the secondary electron emission properties are summarized. The feasibility of diamond like carbon films using as negative hydrogen ions surface conversion materials is analyzed. Diamond like carbon films have both diamond phase and graphite phase, which lead to the good electrical and electron emission properties. Therefore, in the future negative hydrogen ions source, it is expected that the diamond films may be the promising and optional surface conversion materials.

There are a variety of PVD and CVD coating techniques using plasma and energetic beams. However, commonly used industrial coatings involve only a few materials, such as metal nitrides and amorphous carbon. To address such a phenomenon, this paper proposes three basic principles of thin film material selection, i.e., composition tolerance, structural stability and electrical conductivity. Three kinds of typical coating materials are then explained based on the principles, namely titanium nitride representative of solid solution materials, amorphous boride, and Cr-doped diamond-like carbon, stressing that the selection of thin film materials is derived from the balance between process characteristics and material performance, and is dominated by processability. It is pointed out that the material compositions must be precisely regulated to achieve the best matching of processability and performance, while material compositions are rooted in chemical short-range-order structures. By introducing the cluster-plus-glue-atom model developed by our research group, molecule-like local structural units and the corresponding composition formulas are constructed and they explain the compositions of thin film materials in use. The perspective of using this method as thin film composition design is envisaged.

In this paper, the standards related to optical coating technology in the US military standards, ISO standards and Chinese standards are summarized. Among the US military standards, there are 7 optical coating standards, which are classified according to their content. In ISO standards, the main content and development of ISO 9211 are described in detail. In Chinese standards, the current optical coating standards are enumerated and classified. The development of these optical coating standards are prospected. The US military standards will still be active in the optical coating industry for a long time. The optical coating standards of ISO will be constantly improved and widely used in the industry. In China, there will be more and more optical coating standards, and their technical requirements will be in line with the ISO standards step by step.

According to the structure of the vacuum furnace forced cooling system widely used in China at present, and the investigation and theoretical analysis of the advanced forced cooling system in the domestic and foreign markets, it is concluded that the airflow reversed forced cooling system can improve the cooling rate of vacuum furnace and improve production efficiency with reducing energy consumption. It also improves the temperature uniformity of the workpiece, so that the workpiece being treated cools more evenly, and improves the heat treatment quality of the workpiece treated^[1]. Finally, some suggestions are put forward on the structural design and development of air flow change technology for vacuum furnace forced cooling system.

This paper analyzes the scheme of positive pressure leak detection in water vapor jet pump for RH vacuum refining system and the difficulties in the application of this method in the mechanical vacuum pump system. We proposed a method of negative leak detection in the mechanical vacuum pump system, gave the theoretical analysis method, and also compared the theoretical analysis results with the actual test data. The actual leakage rate of vacuum system was measured and the equivalent hole size was calculated. The intelligent leak detection scheme of vacuum system of mechanical pump was discussed, which can quickly find the leak point position, improves the leak detection efficiency of vacuum system, and improves the intelligence level of RH vacuum refining unit.

Aiming at the process and requirement of vacuum dewaxing sintering furnace, this paper desings the air flow passage of vacuum desalting sintering furnace based on the principle of differential pressure carrier gas, and analyzes the design idea and scope of application.

NADCAP project is the process certification of special process production in the supply system of aerospace industry, and is the basis of cooperation with international well-known aviation enterprises. Based on the practical experience of Beijing Institute of Aeronautics and materials in the process of NADCAP certification, this paper shares the personal opinions and experience on the key points of AMS2750E certification, the summary and cause analysis of errors prone to be made in the audit, and the implementation process of corrective measures for nonconformities.

The DFMA technology is an important part for the key technology of concurrent engineering, which runs through the whole process of product development. The DFMA technology has obvious advantages with more and more attention by enterprises. In this paper, based on DFMA theory, in the early design stage of composite molecular pump products, in order to shorten product development cycle, reduce product cost and improve product quality, the manufacturing and assembly of products were analyzed, and we optimized product design by considering various factors such as technicality, technical characteristics and economy. At the same time, the comprehensive evaluation method is adopted to construct the evaluation model and compare the schemes before and after optimization, confirming the rationality and feasibility of the optimization scheme.

The biological payload was carried to the far side of the moon through Chang′e 4 probe and carried out experiments on biological growth.In order to maintain the atmospheric environment for a long time on the lunar surface, it was necessary to strictly control the air leakage rate of the payload container. The internal medium of the sealed biological payload was air, the payload didn′t have leak detection interface, it didn′t allow to be filled with other leak detection gas and couldn′t use the mass spectrum leak detection method.The total leakage rate of the biological payload was tested successfully through the static pressure rise method, the problem of testing the total leakage was solved, and the biological experiment was successfully carried out on the lunar surface.

Pressurization, depressurization and repressruization test is primarily applied to investigate the adaptability of electronic equipment stand-alone products to the depressurization and repressruization environment under the condition of above normal atmospheric pressure. Combining with the characteristics of pressurization, depressurization and repressruization test, we develop a set of pressurization, depressurization and repressruization test equipment. It solves the difficult problems such as gas temperature decrease during depressurization test, condensation on the inner surface of specimens and containers, precise control of rate during depressurization and repressruization, etc. The results prove that all of the test equipment technical indicators meet the technical requirement, which can ensure the smooth process of pressurization, depressurization and repressruization test.

In order to study the discharge process and plasma distribution in Hall thruster channel, a two-dimensional simulation model of Hall thruster was established. The number density and velocity distribution of the Xe⁺ and Xe⁺⁺, current density distribution, potential distribution and electron temperature distribution in the thruster channel were obtained. The discharge process in the thruster was observed from the change of number density distribution of the Xe⁺ and Xe⁺⁺ at different time. The results show that the specific impulse is about 1300S when the discharge is 1300V and 4. 2A, and the gas flow rate is 42SCCM. The results are in good agreement with the experimental and numerical results reported in the literature. On the one hand, the validity of the model in numerical simulation of Hall thruster is verified. On the other hand, the detailed discharge plasma parameters in the steady Hall thruster is obtained.

In this article, a two-dimensional axi-symmetric model of multi-physical porous media is developed to numerically simulate the microwave vacuum drying process. It indicates that, with the increase of environmental vacuum degree during the microwave vacuum drying process, the dried samples can be dried rapidly at a lower temperature, thus the drying efficiency and product quality can be improved. The temperature and water uniformity inside the sample become worse with the increase of ambient vacuum. Therefore, scarification of acceptable amount of drying, decreasing of the total output microwave energy or microwave power can improve the temperature and water uniformity of dried samples.

The low-temperature connector through the wall is used to connect the cable inlet and outlet device. Through the design, simulation, test, and a variety of scheme comparison, it can satisfy the requirement of cable into the device. The design is economic, practical, safe and reliable, rational layout, convenient operation, easy to maintain, and can run stably for a long term solution. The performance of measurement and control cable in low temperature environment meet the requirements.

Ion beam has the advantages of high machining accuracy, good controllability, clean and pollution-free processing surface, etc. Using ion beam to fabricate ultra-smooth optical elements can avoid the subsurface damage caused by traditional machining methods. In this paper, RF plasma was applied for processing of quartz glass, and the polishing effect of RF plasma was studied. The influence of process parameters such as ion beam energy, beam density and angle of incidence on the polishing effect was analyzed. The test results show that the surface roughness RMS first decreased and then increased with the increase of ion beam energy. When the ion beam polishing energy was 600eV, the roughness reached the minimum of 1.73RMS/nm, and when the ion beam beam was 200mA, the roughness reached the minimum of 1.26RMS/nm. As the polishing time increases, the surface roughness decreases and then increases.

For machining metal parts by laser metal melting deposition method, if propose a new method to understand the relationship between the macro processing parameters and the evolution of internal micro structure during the laser metal melting deposition process, the micro structure of the samples can be controlled and the mechanical properties will be thus greatly improved. In this paper, a multi-scale and couple physical field was built by using a double time steps method, and the simulation result was validated by processing experiment using the same processing parameters. At last, a good result was obtained, which is proved to have the guiding significance for selecting LMDS process.

The nickel-coated graphite and graphene composie coatings were fabricated by laser cladding on the 40CrNi2Si2MoV steel substrate, respectively. The phase, microstructure, microhardness, friction and wear property of the composite coatings were investigated. The results show that the microstructure of the coatings consist of γ-Ni, Ni₃B, M₂₃C₆ and M₇C₃, and have the morphological characteristics of hypoeutectic. The results of microhardness measurements show four steps occurring from the surface to substrate, and the subsurface of the coatings has the maximum hardness. Two kinds of coatings have good anti-friction property and wear resistance.

Aiming at the characteristics of the complex mechanical in actual environment of aviation titanium alloy structural parts, the most widely used laser welding of 1.0mm and 2.0mm TC4 thin-walled titanium alloy were taken as the research object in this paper. From the perspective of welding process, the welding process parameters were optimized, the shear performance were tested, as well as tensile performance and bending performance of the joint. In order to further analyze the as-measured mechanical performance results, X-ray and SEM were used to observe the internal quality and microstructure. The results show that laser welding joints with good performance can be obtained using the optimized process parameters, and all indicators of the joint meet the requirements of aviation standard level Ⅰ. This is mainly due to the large temperature gradient and fast cooling speed of the laser welding molten pool, the joint microstructure is mainly composed of tiny needle-shaped martensite distributed in a basket shape that improves the plasticity of the joint and the high temperature endurance strength.