Вакуумний пост для нанесення покриттів на внутрішню поверхню труб методом магнетронного розпилення

Shear horizontal surface acoustic wave (SH-SAW) sensors have been studied for measurements of liquid properties. The long-distance propagation of SH-SAW with multiple wave roundtrips on a pipe surface improve the measurement sensitivity. c-Axis parallel oriented ZnO films can excite the SH-SAW and be grown on a curved surface by a sputtering deposition. In this study, the ZnO film growths on pipe surfaces with various pipe diameters were demonstrated. The c-axis parallel oriented ZnO film with high orientation was only obtained on the pipe surface facing the sputtering target plane. A slit which limits the deposition area and an automatic rotation system of the pipe were effective for the uniform film growth on the entire pipe surface. This film/pipe substrate structure is a good candidate for the SHSAW sensor with high sensitivity.

TiN film was coated on the internal surface of a racetrack-type ceramic pipe by three different methods: radio-frequency sputtering, DC sputtering and DC magnetron sputtering. The deposition rates of TiN film under different coating methods were compared. The highest deposition rate was 156 nm/h, which was obtained by magnetron sputtering coating. Based on AFM, SEM and XPS test results, the properties of TiN film, such as film roughness and surface morphology, were analyzed. Furthermore, the deposition rates were studied with two different cathode types, Ti wires and Ti plate. According to the SEM test results, the deposition rate of TiN/Ti film was about 800 nm/h with Ti plate cathode by DC magnetron sputtering. Using Ti plate cathode rather than Ti wire cathode can greatly improve the film deposition rate.

Some metal compounds called as Non-Evaporable-Getter have been widely used to improve vacuum system performance of accelerator facility. In this paper, a TiZrV film on the surface of stainless steel vacuum pipe is made by direct current magnetron sputtering, and its vacuum performance is experimentally studied. Our results show that the TiZrV film is partly activated at 160 degrees C, and its pressure performance is similar with one at higher temperature. The coating reduces the ultimate pressure and prominently shortens the pressure-down time in a sputter ion pump system, thus creating evenly distributed pressure profile in a coating pipe. The adsorption rate is steady, and adsorption amount increases linearly. Such TiZrV-coated pipe behaves like pump other than gas source in vacuum system.

Corrosion Resistant Alloy (CRA) coating has been developed and assessed as an internal coating on the surface of carbon steel tubings, casings, and pipes which may be applied in H2S/CO2 environment (sour environment). The coated tubular structure can mitigate corrosion caused by H2S/CO2/Cl− and ensure the safety, reliability and integrity for sour oil and gas exploration and production. In this study, CRA C276 (UNS(1) N10276) was selected as the target material and sputter deposited on the internal surface of carbon steel tubings, casings and pipes using a Cylindrical Magnetron Sputtering (CMS) process. The thickness, composition and adhesion of the coating were studied using various techniques. Corrosion and hydrogen permeation tests were conducted in a sour environment. The results show that the UNS N10276 coated samples have obvious anti-corrosion abilities in an H2S environment and the resistant performances are related to coating thickness and adhesion. The preliminary testing results are quite encouraging and will be presented in this paper.

The ZnO piezoelectric coatings were deposited on the surface of 15CrMo steels by magnetron sputtering to directly excite the ultrasonic signal, effectively solving the coupling problem between the traditional probe and the pipe surface. The microstructure, mechanical properties, and ultrasonic longitudinal wave velocity of the aged samples were carried out systematically. The spheroidization grade of pearlite, evolution of carbide morphology, hardness, strength, and ultrasonic wave velocity were systematically analyzed. As the degree of aging intensifies, the material undergoes significant pearlite spheroidization and carbide coarsening. The Vickers hardness drops from 158 HV in the original state to 134.2 HV, and the yield strength and tensile strength decrease by 22.7% and 17.9%, respectively. The ultrasonic longitudinal wave velocity shows a monotonically upward trend with the increase in spheroidization grade, increasing from 5925.6 m/s in the original state to 5976 m/s at the highest spheroidization grade.

Aluminum alloy A6061, which is highly resistant to hydrogen entry, was prepared on a carbide steel cylindrical pipe using a magnetron sputtering deposition method. In this method, plasma was generated between the cylindrical pipe substrate and the cylindrical rod targets, and it moved toward the axial direction with the generation of a modulated magnetic field by a low-frequency alternating coil current. Uniform A6061 thin films were deposited inside the cylindrical pipe using the magnetron sputtering deposition method. The surface morphologies of the films were smooth, and the uniformity of the films was increased by the modulated magnetic field. Moreover, hydrogen content measurements revealed that the A6061 plasma coating is highly resistant to hydrogen entry in corrosive environments, suggesting that the coating was applicable to the elastic deformation region of the base material.

SURFACE MODIFICATION OF UHV WALL BY PLASMA CHEMICAL METHOD

A novel technology for microfabrication of millimeter-band planar microstrip slow-wave structures is considered. The technology is based on magnetron sputtering and laser ablation methods. The magnetron sputtering method is used to deposit a thin layer of metal (copper) on a dielectric substrate. Then laser ablation is utilized to cut a slow wave structure from the copper layer. V-band (50–70 GHz) and W-band (75–110 GHz) meander-line slow wave structures are fabricated and characterized by scanning electron and optical microscopy. Electromagnetic parameters of the developed slow wave structures are studied by numerical simulation. Cold-test measurement are also carried out for microfabricated meander-line slow wave structures. The experimental results are in good agreement with the numerical ones. The proposed technology has significant advantages in cost, speed and flexibility over lithography processes commonly utilized for such applications. The future work will be aimed to expansion of the proposed technology to manufacturing of higher-frequency E-band (110–170 GHz) planar slow wave structures.

The Vacuum Device for Receiving Coatings on the Inner Surface of the Pipes by Magnetron Sputtering

Microwave vacuum devices are used in a wide variety of areas, such as radar, space technology, electron accelerators and high-power microwave weapons at the future military frontiers. The cathodes, i.e., the electron sources, are the cores of the high-power microwave sources. Nanoparticles have many physical and chemical properties that their corresponding bulk materials do not have, such as surface effect and small-size effect, etc. Based on our previous work on the M-type cathode, we have proposed a strategy to develop a new type cathode. We deposited a layer of thin film of metal nanoparticles on the traditional Ba-W dispenser cathode. Thus the N-type cathode demonstrated some features different from the traditional M-type cathode. The study of the electron emission properties of this N-type cathode would promote the understanding on the electron emission and expand the applications of the nanomaterials. Nanoparticle thin films were grown by magnetron sputtering at room temperature. The results showed that the particle size of the films depended on the deposition rate in the nucleation stage of the films. The effect of thin film characteristics on thermionic emission of dispenser cathodes has been investigated. The chemical components of the vacuum background, the evaporants from an N-type cathode and an M-type cathode were respectively analyzed using a time of flight mass spectrometer (ToFMS). The results have proved that the ToFMS is one of the best tools for studying the evaporation phenomena of impregnated cathodes. Finally, the electron emission performance of the N-type cathodes was studied. I-V characteristics showed that the DC emission current density was 30 A/cm2 and its lifetime was 600 h. The pulse emission current density was 108 A/cm2 and its lifetime was 1500 h.

Boron nitride (BN) ceramic is an important support material in aerospace, arc discharge devices, and vacuum electronics. The electron emission properties of BN surfaces are of significance among various space applications. In this work, by preparing BN thin films and microstructured BN bulks, we have investigated the influence of the surface physical properties on the electron emission coefficient (EEC). The results showed that the surfaces of BN films, which were prepared by magnetron sputtering, produced serious gas adsorption and organic contamination when they were left for 10 days, and these surface modifications made the EEC of BN film surface decrease to a certain extent. The argon ion cleaning experiments indicated that the process of ion cleaning was able to partly eliminate the surface adsorption and contamination for the BN film. The EEC of the cleaned BN film surface was significantly improved compared to that of the original polluted BN film surface, with an EEC peak value of about 3.2 instead of 3.0 for the original polluted surfaces. By contrast, the EEC curves of the BN bulk show some difference, with the peak values of the EEC curves being 2.62 for the untreated BN bulk. The results of laser etching on the BN bulk surface to form microarray structures show that the EEC of BN bulk decreases significantly with the increase of the average aspect ratio of the microstructures. The EEC peak values of the BN bulks decrease from 2.62 to 1.16 when the porosity of the BN bulk reaches 49.11% and the aspect ratio reaches 1.36, indicating that constructing a surface microstructure is an effective method to achieve EEC reduction. By employing the electron trajectory tracking algorithm and the phenomenological model of electron emission, the effect of microstructure on EEC for BN bulk was quantitatively explained. The results of the study are of engineering application significance for vacuum devices involving the electron emission process of BN ceramic.

Study on hydrogen absorption performance of the modified Zr/ZrVFe porous getters

TiZrV has been used in vacuum technology and electric vacuum devices due to its high pumping speed and low activation temperature in recent years. At the same time, many preparation methods have been developed. Different from the current coating method of magnetron sputtering, this paper discusses the preparation of thin film coating from the viewpoint of vacuum sintering, which is flexible in design and more suitable for operation. Based on the analysis of the surface morphology of the sintered film, the feasibility and operability of the experimental method were explored from the surface compactness of the getter.