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The purpose of this paper is to present thermal properties of palladium-carbon films prepared by physical vapour deposition (PVD)/chemical vapour deposition (CVD) methods.

Thin palladium-carbon films were prepared at Tele- and Radioresearch Institute. Test structures containing palladium-carbon films and titanium electrodes were made. Temperature-resistance characteristics were measured.

The results show strong temperature dependence of modified carbon film resistance. The dependence is stable, and so modified carbon films can be applied for various electronic applications.

The paper presents thermal properties of thin palladium-carbon prepared by original PVD/CVD method at Tele- and Radioresearch Institute.

Immersion is one of the key steps during the preparation of silane-based hybrid films, which has important effects on the performance of films after curing. In this paper, the formation process of Zr-doped silane film (i.e. the adsorption of silane and deposition of zirconium compounds) on carbon steel immersed in Zr(NO₃)₄/silane mixed solutions was investigated.

The method of in situ monitoring the open circuit potential of a two-electrode system, consisting of carbon steel and saturated calomel electrode, was used. The effects of immersion conditions (i.e. the concentration of Zr(NO₃)₄ and pH of Zr(NO₃)₄/silane mixed solution) on the open circuit potential were investigated in detail. Furthermore, the surface coverage rate of different cured films (i.e. Zr cured film, silane cured film and Zr/silane composite cured film) after curing on carbon steel was calculated according to the results of polarization curves. Electrochemical impedance spectroscopy (EIS) was used to study the self-healing property of Zr-doped silane cured film.

The results indicate that in Zr(NO₃)₄/silane mixed solutions, most zirconium compounds deposit on the surface of carbon steel at the initial immersing stage, then the adsorption of silane on the residual surface of carbon steel dominates the following immersing stage. EIS results show that the Zr-doped cured film has improved self-healing property.

First, the method of in situ monitoring the open-circuit potential of two-electrode system was applied to investigate the deposition of Zr and the adsorption of silane on carbon steel immersed in Zr(NO₃)₄/silane mixed solutions. Second, the formation process of Zr-doped silane film was proposed.

The purpose of this work is to reveal the mechanism of WO₄²⁻ on surface passivation for Q235 carbon steel in tungstate solution.

In Na₂WO₄ solutions with the different concentrations of WO₄²⁻, the spontaneous passivation occurred on the surface of Q235 carbon steel when the concentration of WO₄²⁻ was up to 0.13 mmol/L, which was attributed to the formations of the inner deposition film and the outer adsorption film on the Q235 surface under the action of WO₄²⁻.

The inner deposition film presented a two-layer microstructure: the inside layer was composed of Fe₂O₃ mainly, and the outside layer comprised Fe(OH)2•nH₂O, Fe(OH)3•nH₂O, FeWO₄ and Fe₂(WO₄)3.

Both FeWO₄ and Fe₂(WO₄)3 repaired the defects in the outside layer of the inner deposition film; however, the outer adsorption film played a more important role in the surface passivation than the inner deposition film did.

Solid thin films have been deposited on stainless steel 314 (SS 314) substrates in a chemical vapor deposition (CVD) reactor at different flow rates of natural gas mostly methane (CH₄). The purpose of this paper was to investigate experimentally the variation of thin film deposition rate with the variation of gas flow rate.

During experiment, the effect of gap between activation heater and substrate on the deposition rate has also been observed. To do so, a hot filament thermal CVD unit is used. The flow rate of natural gas varies from 0.5 to 2 l/min at normal temperature and pressure and the gap between activation heater and substrate varies from 4 to 6.5 mm.

Results show that deposition rate on SS 314 increases with the increase of gas flow rate. It is also seen that deposition rate increases with the decrease of gap between activation heater and substrate within the observed range. These results are analyzed by dimensional analysis to correlate the deposition rate with gas flow rate, surface roughness and film thickness. In addition, friction coefficient and wear rate of SS 314 sliding against SS 304 under different normal loads are also investigated before and after deposition. The obtained results reveal that the values of friction coefficient and wear rate are lower after deposition than that of before deposition.

In this study, thin film deposition rate on SS 314 was investigated using CVD. The obtained results were analyzed by dimensional analysis to correlate the deposition rate with gas flow rate, surface roughness and film thickness. The friction coefficient and wear rate of SS 314 were also examined before and after deposition.

The purpose of this paper is to investigate the deposition of uniform, adherent and crack‐free Ni‐P thin films on carbon fibres using the electroless deposition technique.

Before applying the electroless process, the carbon fibre surfaces must be subjected to several treatment processes to remove the organic binder, etching and surface metallization. The surface morphology of the Ni‐P coatings was assessed using a scanning electron microscope (SEM). The chemical compositions of Ni‐P layers were identified by energy dispersive X‐ray analysis (EDS). The bond strength of the coated layer was determined by measuring the electrical resistance at the fibre/coating interface. The magnetic properties of the fibres were estimated using a hysteresis diagram. The tensile performance of single fibres coated by Ni‐P has been investigated with respect to coating thickness.

Pre‐treatment processes are used to improve the adhesion of Ni‐P layers and to obtain homogeneous coatings. The influence of plating parameters (temperature, pH and time) on the coating thickness of the Ni‐P layer was investigated. It was found that the coating thickness increased as the pH value, plating time and the temperature of the bath increased. The results revealed that a complete and uniform Ni‐P coating on fibre could be obtained at optimum conditions 85°C, pH 6, for 60 min, and the results indicated that the P content in the electroless deposit is approximately 3.4 wt%. The tensile strength values are improved significantly after coating and increased by 3‐5 times with increasing of coating thickness from 0.3 to 2 μm.

The results presented in this work are an insight into understanding of the deposition and adherence of Ni‐P thin films on carbon fibre using the electroless technique and behaviour of the coated fibre.

Carbon steel has a high application rate in modern industry, but this type of steel has the defect of high wear. This study aims to improve the surface friction and wear performance of carbon steel under such working conditions.

In this study, a dry film lubricant based on graphite powder was prepared by the ultrasonic dispersion method, and deposited on the surface of carbon steel specimens by the simple pressure spraying technology. At the same time, molybdenum disulfide and polytetrafluoroethylene dry film lubricants were developed by the same method, and the comparative experimental study on friction and wear was carried out in the end-face friction tester.

The results show that the deposition effect of graphite and molybdenum disulfide dry film lubricants on the surface of carbon steel is obviously better than that of polytetrafluoroethylene dry film lubricant. Compared with molybdenum disulfide and polytetrafluoroethylene dry film lubricant, graphite dry film lubricant has the best friction and wear performance on the surface of carbon steel. The working life of carbon steel specimens sprayed with graphite dry film lubricant decreases with the increase of pressure load and rotation speed. The combination of load and sliding speed will accelerate the transition of the coating to a stable direction. In addition, the micro lubricant particles formed in the wear process will form particle flow lubrication, and the appropriate addition of particle powder of the same material will also prolong the normal antifriction time of the lubricant.

These findings developed a dry film lubricant that can effectively improve the friction and wear properties of carbon steel surface.

The purpose of this paper is to evaluate the use of nickel and nickel oxide thin films as anticorrosive protection for low‐carbon steel when expose to sour media. The purpose of this paper is also the study of a superior oxide nickel thin film over the nickel thin film.

Nickel thin films are applied on steel AISI 1018 (UNS G 10180) by magnetron sputtering and electrolytic techniques. The films are tested after deposition on low‐carbon steel. A massive nickel electrode also is evaluated as a reference. In order to evaluate the protective properties of films in sour media, electrochemical techniques are employed, but also scanning electron microscopy in order to identify the difference in porosity and surface of the films coated by both techniques.

Micrographs of thin films deposited by magnetron sputtering reveal a homogeneous surface whereas the electrolytic films show many micro‐crevices and expose the substrate even on the oxide films. These results indicate that localize corrosion on the film surface diminishes the corrosion resistance, even if the film itself has a superior corrosion resistance.

These kinds of nickel thin films deposit by magnetron sputtering and their oxides are an excellent anticorrosion alternative even for mild carbon steel exposed on sour media.

The sputtered nickel deposit is consistently more protective against corrosion than an electrolytic deposit of the same thickness. The nickel oxide benefits the steel by displacement of the corrosion potential towards more positive values. The electrochemical performance of solid nickel oxide is superior compared to the nickel metallic film on the steel substrate.

The purpose of this paper is to improve the corrosion resistance of stainless-steel bipolar plate by magnetron sputtering.

TiC/amorphous carbon composite film was deposited by magnetron sputter at four different temperature of 25°C, 200°C, 300°C and 400°C. The morphology, composition and structure of the film were characterized by scanning electron microscopy, atomic force microscopy and X-ray photoelectron spectroscopy. And its corrosion behavior was analyzed through electrochemical impedance spectroscopy, potentiodynamic and potentiostatic polarization tests.

A compact TiC/amorphous carbon film was prepared by magnetron sputtering on 316L stainless steel, and the particles of the film were refined with the increase in sputtering temperature. High temperature promoted the formation of TiC and C–C sp² hybrid carbon, but excessively high temperature caused the oxidation of Ti and a significant decrease in sp² hybrid carbon. The corrosion resistance of the film increased with the temperature, and the corrosion current density polarization at 0.86 V and 1.8 V for TiC/a–C film prepared at 400 °C is only 1.2% and 43.2% of stainless steel, respectively.

The corrosion resistance of amorphous carbon films was improved by the doping of Ti carbide, and the appropriate sputtering temperature was obtained.

Three types of pattern on the monocrystalline silicon surface were prepared by using laser surface processing equipment. The DLC film and Si-DLC film on the patterning surface were deposited by using PECVD-2D plasma chemical vapor deposition sets. The paper aims to discuss these issues.

The tribological properties of the films were investigated by using the UMT-2 micro friction and wear tester. The surface topography, composition, hardness and elastic modular of the films were determined by Raman spectrum, nano mechanics tester and three-dimensional topography instrument. The worn surface topographies of the surface patterning films were tested by scanning electron microscopy.

The results show that the patterning monocrystalline silicon substrate surface has good anti-friction property under low load. The patterning DLC film and Si-DLC film surface have very good anti-friction property under all the test loads. The reason of these results is that the surface patterning film not only reduces the real contact area of the friction pairs but also has low surface bonding force.

This paper prepared three kinds of microscopic patterns on the monocrystalline silicon surface by using laser surface processing equipment. And then deposited DLC film and Si-DLC film on the patterning surface. All kinds of surface patterning monocrystalline silicon had very good anti-friction property under low load. And all kinds of surface patterning nano-hard film had perfect anti-friction property under all test loads.

This study aims to obtain diamond-coated mechanical seals with improved sealing performance and considerable cost. To achieve this purpose, the study focuses on depositing uniform, wear-resistant and easily polished diamond coatings on massive mechanical seals in a large-scale vacuum chamber.

The computational fluid dynamics simulation test and its corresponding deposition experiment are carried out to improve the uniformity of diamond films on massive mechanical seals. The polishing properties and sealing performance of mechanical seals coated with three different diamond films (microcrystalline diamond [MCD], nanocrystalline diamond [NCD] and microcrystalline/nanocrystalline diamond [MNCD]) and uncoated mechanical seals are comparatively studied using the polishing tests and dynamic seal tests to obtain the optimized diamond coating type on the mechanical seals.

The substrate rotation and four gas outlets distribution are helpful for depositing uniform diamond coatings on massive mechanical seals. The MNCD-coated mechanical seal shows the advantages of high polishing efficiency in the initial polishing process and excellent wear resistance and self-lubrication property in the follow-up polishing period because of its unique composite diamond film structures. The MNCD-coated mechanical seal shows the longest working life under dry friction condition, about 14, 1.27 and 1.9 times of that for the uncoated, MCD and NCD coated mechanical seals, respectively.

The effect of substrate rotation and gas outlets distribution on temperature and gas flow field during diamond deposition procedure is simulated. The MNCD-coated mechanical seal exhibits a superior sealing performance compared with the MCD-coated, NCD-coated and uncoated mechanical seals, which is helpful for decreasing the operating system shut-down frequency and saving operating energy consumption.