Heat treatment and vacuum coating are technologies that give parts superior performance. They have played an important role in many aspects of the national economy. In recent years, with the development of high-tech products and high-end manufacturing needs, these two techniques are becoming integrated. This article presents an example of the two technologies merging and helping each other. Heat treatment professionals should learn the technical knowledge of vacuum coating. “Vacuum coating technology” should be set as one of the basic courses for “heat treatment professional ”and “material professional” majors.

In order to improve the high temperature oxidation resistance of superalloy, NiCrAlY coatings were deposited on DZ22B superalloy by cathode arc ion plating. Scanning electron microscopy was used to observe the surface and cross-section morphology of the coatings. The volumetric analysis was applied to test the composition of the coating, X-ray diffraction was used to analyze the phase composition of the coating, and adhesion of the coatings was measured by universal testing machine. The results show that the thickness of NiCrAlY coating is about 50 μm, and the coating is compact and well bonded with the substrate. The composition of the coating is basically the same with target except for the small loss of Al. The main phase of NiCrAlY coating is γ′-Ni₃Al/γ-Ni, with a small amount of β-NiAl phase. During the high temperature oxidation process, a dense Al₂O₃ layer was quickly formed on the surface of NiCrAlY coating, therefore provide good oxidation resistance protection for substrate at 1050 ℃. The failure of the coating should be caused by the continuous growth of cracks in oxide layer and finally exfoliation, resulting in the consumption of antioxidant element.

Molybdenum disulfide films were prepared under different pressures by RF reactive magnetron sputtering. The surface morphology, structure and optical properties of the films were characterized by scanning electron microscopy, X-ray diffractometry and UV-Vis spectrometer. The results show that the surface of MoS₂ films prepared by RF reactive magnetron sputtering is smooth, uniform and compact with few defects. The films prepared under the deposition pressure of 1.2Pa shows the best crystallinity. The optical band gap of the films increases first and then decreases with the increase of deposition pressure. The optical band gap is the largest at 1.2Pa, which is 1.69eV. The change in the optical band gap of the film is caused by the change in crystallinity of the films and the formation of defects due to the deposition gas pressure.

According to the application requirements of polychromatic fluorescence detection, a design method of coating system for multi-pass filter was proposed in this paper. This method was based on the traditional Fabry-Perot model, and the basic coating system was formed by nesting the bandpass model. By calculating and adjusting the peak position factor and the bandwidth matching coefficient, the bandpass positions and bandwidths of the basic coating system can be adjusted continuously. After optimizing by Essential Macleod software, the good waveform which has rectangular passband and deep blocking can be obtained.

Anatase TiO₂ thin films were fabricated by DC magnetron sputtering technology(DCMS). The effects of the substrate temperature, pressure and sputtering power on the deposition rate of TiO₂ films were studied. The surface morphology, structure and film thickness of the samples were characterized by field emission scanning electron microscopy(FESEM), X-ray diffractometer(XRD)and elliptical polarizer. The experimental results showed that the thin film was prepared as the single anatase phase and the surface is uniform. With the increase of the deposition temperature, the deposition rate of the thin film increased from 2.16nm/min to 4.03nm/min at the temperature from 100℃ to 400℃; The depositing rate decreased when the pressure increased. The deposition rates at the conditions of 0.75PA, 1.5 Pa and 3.0Pa are 4.48nm/min, 3.18nm/min and 2.42nm/min, respectively; The depositing rate increased as the sputtering power increased. The deposition rates corresponding to 100W, 295W, and 443W were 2.95nm/min, 3.18nm/min, and 7.50nm/min, respectively. In the end, double-layer TiO₂ film was designed on the glass substrate using the TFC film system design software. The film was prepared on the ground of results. The experimental value and the theoretical design results are very consistent.

The CuO thin films were deposited on glass substrates by puls laser deposition and the effects of substrate temperature on the structural, electrical, and optical properties of CuO thin films were investigated. Thin films deposited at different substrate temperature under 8 Pa were all CuO. All CuO thin films exhibited a transmittance higher than 65% in the NIR range. Increasing the substrate temperature to amoderate level(300 in this study)accompanied improved crystalline quality, which yielded the lowest electrical resistivity of 2.33×10²Ωcm with the highest carrier concentration of 5.28×10¹⁶1/cm³ and Hall mobility of 1.26cm²/(VS). The most important is that CuO achieved from p-type to n-type at above 500℃. The n-type characteristics need to be improved to make these films useful for applications like transparent p-n junction based devices.

CrAlNx coating was deposited onto roll surface of 45 steel by vacuum ion plating, and the production technology of CrAlNx coating was optimized. The friction performance of CrAlNx coating was studied. The results show that the friction coefficient of CrAlNx coating decreases with the increase of speed and load under the condition of GCr15. With the increase of the loading and sliding speed, the wear rate under the condition of the GCr15 accessory is increased, and the wear mode of the GCr15 is mainly shown as the mixed form of adhesive wear and abrasive wear.

It is one of the main failure modes for dental implant system that fretting fatigue occurs at the implant-bone interface and fretting wear occurs at the interface between the connection components. Therefore, reducing the micromotion and improving the longevity of implant system have become the key factors for successful application. This review article focuses on the research progress of the instable problems caused by fretting fatigue at the implant-bone interface and the connection failure due to fretting wear between the internal interfaces of implant system. Surface modification technology plays a key role in improving osseointegration rate, wear resistance, and fatigue resistance of implanted devices. However, all the traditional coating technology gradually withdrew from the historical stage due to the increased new interface and the risk of long-term shedding. Based on the review for current researches, it is believed that some modern techniques（such as low energy ion implantation methods）have many advantages, such as gradient composition change from top surface to body substrate, long-term stability, and so on, which are becoming the key technologies for fretting damage control and are becoming a new trend in biomedical device development.

On the basis of the lunar exploration project, further deep space exploration is the future development trend. In the following deep space exploration activities, it will inevitably involve sampling and return of extraterrestrial objects. Sample sealing technology provides technical support for deep space exploration samples returning. According to the requirements of brazing seal in deep space exploration sample collection in China, this paper reviews the development status of brazing seal technology in deep space exploration missions abroad. It mainly introduces two specific types of brazing seal containers including double-layer brazing seal container and single-layer brazing seal container. Meanwhile briefly introduces the current status of brazing seal technology in China. Finally, according to the application need of China′s asteroids and Mars exploring tasks, work recommendations for brazing seal used in deep space exploration sample collection in China are proposed.

As the third generation of rare earth permanent magnet material, NdFeB occupies a pivotal position in the magnetic materials field. NdFeB is widely used in fields such as national defense, aerospace, information communications, automobiles, energy, energy conservation, environmental protection and medical equipment. However, the low resistance of NdFeB to corrosion limits its application to further expand. The phase composition, corrosion process and corrosion products of NdFeB are reviewed in this study. The corrosion characteristics of NdFeB such as high temperature oxidation, wet heat hydrogen absorption and electrochemical corrosion were described. The corrosion protection technology of NdFeB is discussed from the aspects of corrosion resistance improving and surface coating protection, focusing on the basic principles, research progress and development direction of electroplating, electroless plating, organic coating and physical vapor deposition. The research of NdFeB corrosion protection technology is the key to promote the application of NdFeB permanent magnets.

The RH refining process plays a vital role in the quality of molten steel. The mixing characteristics of RH directly affect the quality of molten steel, whether the RH equipment can run smoothly and the efficiency of secondary refining.In this paper, the hydraulic model of 1:4 is established. Using the control variable method, KCl powder was sprayed in the RH riser position of the water model to replace the desulfurizer in the actual production. The effects of insufflation amount, the immersion depth of the dip tube and the vacuum degree on mixing time were studied. It is shown that the shorter the mixing time of the powder and liquid steel in the RH refining furnace, the better the refining effect. The larger the blowing amount in a certain range, the greater the immersion depth, and the greater the vacuum degree, the shorter the mixing time.

In this article, the influence of the ionization gauge position on the measurements was simulated by the method of Monte Carlo. The vacuum container, gauge position and flanges were established. The material outgassing was taken into account. The ionization gauge installed at different positions was calculated. The influence of distance between ionization gauge probe and piping flange entrance on the measurement was calculated too. The results show that compared with the installation position of ionization gauge, the distance between the probe of ionization gauge and the pipe orifice shows more influence on the measurement. This paper provides a theoretical basis for the design of piping flange length and the prediction of actual vacuum.

In this paper, the low-pressure DC discharge process of a narrow-electrode discharge device with quartz plate interlayer was studied. The influence of electrode structure and material on plasma parameters was discussed. The electrode width is 4 mm and the spacing is more than 40 mm. The experiments were carried out by using the double probe needle method. The influence of electrode structure on the electron density distribution and electron temperature of the home-made DC plasma discharge device was analyzed by changing the pressure and discharge power. The results show that the plasma density can be effectively increased by increasing the surface area of the electrode and adopting special electrode structure. It was also found that with the decrease of air pressure, the positive cylinder area decreases gradually, the plasma density changes gently along the direction of electric field, and the DC plasma density of the anode increases gradually. At this time, the uniformity of plasma spatial distribution increases, and the maximum value is obtained at 16Pa.

The effect of high temperature(160~320)℃ on the helium leak detection results of TVS-2M fuel rod was investigated. The leak detector is used to analyze the change of leak rate value under different temperatures, and to explore whether high temperature affect the leak detection results and influencing factors. Through the experiment, the fastest temperature range and time of outgassing were obtained. The following conclusions are drawnthe main reason for the increase of helium leak detection results under high temperature is the venting of tvs-2m fuel rod; the fastest venting rate of TVS-2M fuel rod is at(200-220)℃; prolonging the residence time of TVS-2M fuel rod at(200~220)℃ can eliminate the effect of the increase of helium leak detection results caused by venting; when the holding temperature is at(200~220)℃ and the holding time is at(1~1.5)h, TVS-2M helium leak detection results of fuel rods are true and accurate.

Based on the requirements of vacuum DC arc furnace for supporting DC power supply, this paper analyzes the principle, advantages and disadvantages of the main circuit scheme of DC arc furnace power supply in common use. The main circuit scheme of power supply for vacuum DC arc furnace is obtained. It is shown that the performance of the high voltage of power grid through the rectifying transformer for a primary buck and the rectifier transformer secondary side with thyristor phase-controlled rectifie is still the best.

The generation and transmission process of the neutral beam requires a vacuum gradient distribution environment. It is very important to accurately get the vacuum degree and its distribution in the vacuum chamber for the commission and operation of the neutral beam. Affected by the temperature of the wall in different areas of a cryo-vacuum space, the gas temperature in the vacuum chamber has a specific distribution characteristics, which has a critical impact on accurate measurement and final determination of the vacuum degree. Based on the Molflow software, the collision frequency and gas molecular density distribution of gas molecules in the vacuum chamber of the full superconducting tokamak neutral beam injector were simulated, and the gas temperature distribution in different regions of the vacuum space was obtained. It provides temperature basis for the amendment of specific vacuum measurement points, and improves the measurement accuracy of the vacuum degree.

The paper analyzes the working principle and process of the liquid ring vacuum pump and the liquid ring compressor. It is the first time that the different design concepts of the vacuum pump and the compressor are put forward. The geometric design method of the liquid ring pump is analyzed. Based on the energy transfer and conversion, the liquid ring compressor is designed by the energy conversion calculation method. According to the change of the gas required in the process, it is transformed into the design input of differential pressure and compression ratio of the compressor, and the mathematical model of the energy conversion foundation is established. By transforming the kinetic energy of the liquid ring into the pressure potential energy, the necessary kinetic energy suitable structure of the compressor is determined, and the basic parameters of the compressor structure are provided. Through theoretical calculation, the trend line of compressor's maximum pressure is given. The application of this design method shows that the liquid ring compressor can realize different outlet pressure, and can realize the comprehensive and compound utilization of vacuum-pressure. Combining with engineering practice, the suggestion of compressor individualization, safety and energy saving is put forward. It is suggested that the index of liquid ring compression should be checked by systematic method to promote engineering practicality and compressor technology development.