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The purpose of this study is to design and develop a new functional coating system for aerospace AL7075-T6 alloy that would evaluate the mechanical properties of the coating.

This paper outlines the scratch adhesion characterisation of Cr/CrAlN coating using a combination of radio frequency (RF) and direct current (DC) physical vapour deposition (PVD) magnetron sputtering. The surface morphology, microstructure and chemical composition of the Cr/CrAlN film were evaluated by optical microscopy (OM), field emission scanning electron microscopy (FESEM) integrated with energy-dispersive X-Ray spectroscopy (EDX) and atomic force microscopy (AFM). The film-to-substrate adhesion was measured by a scratch test machine manufactured with a detection system, motorized stages, penetration depth sensors, optical microscope and tangential frictional load sensors.

The AFM and ultra-micro hardness results showed an increase in surface roughness to about 20 per cent and hardness to about 74 per cent. Moreover, the film-to-substrate adhesion strength of 1,814 mN was obtained with PVD deposition process.

The main limitation of this work is caused by PVD deposition process. Besides, surface defects such as pinholes contribute to a decrease in adhesion strength.

The higher hardness of CrAlN coating is used to improve the properties of softer aluminium substrates. This hardness prevents ploughing-induced wear and provides greater adhesion strength by preventing coating delamination.

Until now, CrAlN is coated only on ferrous alloys. It has not yet been tried on aluminium alloys. Moreover, coating functionality depends on higher adhesion and failure mechanisms involved in the film-to-substrate system, which is significant in aerospace applications.

Preparing CrAlN coatings on the surface of silicon nitride bearings can improve their service life in oil-free lubrication. This paper aims to match the optimal process parameters for preparing CrAlN coatings on silicon nitride surfaces, and reveal the microscopic mechanism of process parameter influence on coating wear resistance.

This study used molecular dynamics to analyze how process parameters affected the nucleation density, micromorphology, densification and internal stress of CrAlN coatings. An orthogonal test method was used to examine how deposition time, substrate temperature, nitrogen-argon flow rate and sputtering power impacted the wear resistance of CrAlN coatings under dry friction conditions.

Nucleation density, micromorphology, densification and internal stress have a significant influence on the surface morphology and wear resistance of CrAlN coatings. The process parameters for better wear resistance of the CrAlN coatings were at a deposition time of 120 min, a substrate temperature of 573 K, a nitrogen-argon flow rate of 1:1 and a sputtering power of 160 W.

Simulation analysis and experimental results of this paper can provide data to assist in setting process parameters for applying CrAlN coatings to silicon nitride bearings.

The purpose of this paper is to address the influence of deposition process parameters. The substrate heating mechanisms are also discussed.

Deposition duration, sputtering power, working gas pressure, and substrate heater temperature on substrate heating in the direct current (DC) magnetron sputtering deposition process were investigated.

Results from the experiments show that, in DC magnetron sputtering deposition process, substrate heating is largely influenced by the process parameters and conditions.

This paper usefully demonstrates that substrate heating effects can be minimized by adjusting and selecting the proper sputtering process parameters; the production cost can be reduced by employing a higher sputtering power, lower working gas pressure and shorter deposition duration.

TiN and TiAlVN films have been prepared by DC magnetron sputtering technique at room temperature. TiN target has been used to deposit TiN thin film under pure argon (100 percent Ar) gas. Additionally, Ti6Al4V alloy target has been used to deposit TiAlVN under nitrogen and argon gas (50 percent Ar and 50 percent N₂). In this paper, two substrate types have been used: stainless steel 304 and Si(100). This analysis has confirmed that the nitride films, (TiN/Si) and TiAlVN in both cases, have been produced. Energy Depressive X-ray Spectroscopy (EDX) measurement confirmed that the TiN/Si was stoichiometry, where the N/Ti ratio was about 1 with low oxygen contamination. The results obtained have indicated that the TiAlVN has more resistance to corrosion than TiN film in 3.5 percent NaCl at 25°C (seawater). Both films, TiAlVN/SS304 and TiN/SS304, have shown improved corrosion resistance compared with virgin 304 substrate. Microhardness was carried out using Vickers method; the microhardness values for TiN/SS304 and TiAlVN/SS304 were approximately 7.5 GPa and 25.3 GPa, respectively. The paper aims to discuss these issues.

The films were prepared by a DC magnetron sputtering system starting from high pure (99.99 percent) Ti6Al4V target (Al 6wt%, V 4wt% and balance Ti) in plasma discharge argon/nitrogen (50 percent Ar and 50 percent N₂) for deposition of TiAlVN film. Pure TiN target (99.99 percent) was used for preparation of TiN film in pure argon plasma. The diameter of target was 50 mm and the power applied for preparation of the two films was 100 W. A cylindrical high-vacuum chamber (Figure 2) made of stainless steel 316, with height 363 mm diameter, was fabricated locally. Scanning electron microscope images have been used to discover the films morphology. The composition of the films has been determined by EDX technique for films deposited on Si substrate. The electrochemical corrosion test was carried out using conventional three-electrode cell of 300 ml capacity by using Voltalab PGZ 301 system (France) using Tafel extrapolation method and electrochemical impedance spectroscopy techniques.

TiN and TiAlVN films have been prepared by DC magnetron sputtering technique without heating of the substrates holder. The effects of the composition of nitride films on mechanical and corrosion properties were investigated. The composition of the films has been determined by EDX technique. The effect of using titanium alloy (Ti with Al and V) on the composition and crystalline quality has been investigated. The microhardness is strongly dependent on the addition of the Al and V elements, and it consequently improves mechanical proprieties. The microhardness values for TiN/SS304 were approximately 7.5 GPa and 25.3 GPa for TiAlVN/SS304. They indicate that prepared films prevent the aggressive action of corrosion media.

TiN and TiAlVN films have been prepared by DC magnetron sputtering method at room temperature. Titanium nitride film, especially TiAlVN, is an effective method to improve the corrosion resistance of SS304. TiAlVN film has exhibited enhanced corrosion resistance and higher microhardness. Independent time-of-flight elastic recoil detection analysis has been used to determine the composition of the film.

The aim of the present paper is to investigate the mechanical performance of multi-layer films. With the wide application of optic and electronic thin-films, membrane materials and membrane technology have become one of the most active fields of research in contemporary materials science (Dumont et al., 1997). Multi-layer films have evolved as candidates for these applications because of their unique properties. TiN and Ti/TiN multi-layer films were fabricated using the DC magnetron sputtering method. A nano-indentation tester and electronic film distribution tester were utilized to evaluate the mechanical properties and residual stress of the films. The existence of interface effects on the mechanical properties and corrosion resistance of the films were analyzed.

In this study, the Ti/TiN multi-layer films were fabricated using the DC magnetron sputtering method. The films were deposited on polished 45# steels. Ti was used as the sputtering target. Ar and N₂ were applied as working and reactive gases, respectively. Surface morphology was measured using transmission electron microscopy. The composition was analyzed using D8 X-ray diffraction. Nano-indentation tests were performed using Nanoindenter G200 with a Berkovich indenter. A BGS 6341 electronic film stress distribution tester was used to measure the distribution of stress in the films.

The film surface was very smooth and the structure was very dense. The elastic modulus and micro-hardness of Ti/TiN multi-layer films were smaller, compared to those of the TiN film. Furthermore, both of these parameters initially decreased and later increased, with a decrease in the modulation period. The residual stress in the film was compressive. The corrosion resistance properties of TiN films were the best in NaCl solution, less so in alkaline solution and worst in acid solution. For the Ti/TiN multi-layer films tested in an acid medium, the corrosion resistance performance was better when the modulation period was decreased to micron grade under exposure conditions at ambient temperature.

In the present paper, the Ti/TiN multi-layer films were fabricated using PVD with different variations, and the influence on the performance of Ti/TiN multi-layer films due to each single layer period of TiN was studied. The findings should provide useful guidelines for the preparation of high quality Ti/TiN multi-layer thin films.

The purpose of this paper is to present the influence of modifying the fabric surface made from basalt fibers by the magnetron sputtering of chromium and aluminum layers on its resistance to contact heat and comfort properties.

In order to modify the surface of basalt fabric, the process of physical deposition from the gas phase was used. It relies on creating a coating on a selected substrate by applying physical atoms, molecules or ions of specific chemical compounds. The trial of modification was carried out using the magnetron sputtering method due to the material versatility, application flexibility and ability to apply layers on substrates of various sizes and properties.

The findings obtained regarding the heat resistance to contact heat and thermal insulation (comfort) properties show different values depending on the type of metal deposited and the thickness of coating layer. It was found that the modification of basalt fabric surface at the micrometer level changes the tested parameters.

This paper presents the results of resistance to contact heat and thermal insulation properties only for the twill fabric made of basalt fiber. The surface modification of fabric was carried out using the chromium and aluminum of two values of layer thickness (1 and 5 µm).

So far, no tests have been carried out to modify the surface of fabric made from basalt fiber yarns using the magnetron sputtering method. In addition, it has not been studied, how the modification of fabric affects its resistance to contact heat and thermophysiological properties.

The purpose of this study is to investigate the high-temperature behavior of newly developed high-impulse power magnetron sputtering system (HIPIMS) coatings and compare them to the standard TiAlCr system deposited on to a Ti–Al intermetallic alloy. The corrosion test was performed in air for 4,000 hours at 850°C.

In this study, air oxidation test was performed at high temperature. Design and methodology is described in detail in the methodology section in the submitted manuscript. The test was carried out by discontinuous exposure of the three different systems produced by different deposition technique. The exposed samples were investigated using scanning electron microscope coupled with energy dispersive X-ray spectroscopy. The exposed samples were investigated from the surface and cross-sections.

The performed study shows that HIPIMS coatings had a much better oxidation resistance at a high temperature than that offered by the standard physical vapor deposition (PVD) system. HIPIMS costing developed Al–Cr oxide on the surface; however, cracks and detachments were found at the interface between the coating and the substrate. TiAlCr coating spalled off from the material due to the critical thickness reached; moreover, high brittleness and lack of adherence were found. Due to poor oxidation resistance, TiAlCr coating was discarded from the test after 3,000 hours of exposure.

The work performed in this study was designed for 4,000 hours oxidation at 850°C. The long-term exposures are not commonly met in the research work due to the cost and time. The work clearly shows differences between new type of coatings and standard PVD system applied on TiAl lightweight alloy.

The purpose of this paper is to obtain a multidisciplinary characterization of nanostructured copper films for electromagnetic shields.

Structural and electrical analysis have been applied, on copper nanometric films produced by a magnetron sputtering device.

Data are provided for copper films realized by magnetron sputtering deposition on glass, in different operating conditions.

A multidisciplinary comprehension of shielding effectiveness of nanostructured thin films can be important in many applications where there are electromagnetic compatibility problems.

The paper gives a valuable set of information for the characterization of nanometric copper thin films.

To investigate the protective properties of tantalum nitride (TaN) thin films deposited on to various steels immersed in a 3 per cent NaCl solution.

TaN thin films with a thickness of 250 nm were deposited on UNS G10180, UNS S30400 and UNS T11302 steels by means of magnetron sputtering technique. The electrochemical behaviour has been studied in 3 per cent NaCl solution using electrochemical impedance spectroscopy and potentiodynamic polarization. The crystalline structure of the films was investigated by X‐ray diffraction. Surface analysis of the corroded samples was performed using scanning electron microscopy and light optical microscopy. The electrochemical impedance spectra were analysed in the context of equivalent circuit models (ECs).

The ECs incorporate a charge transfer process representing the TaN film on UNS G10180 steel, two time constants for that deposited on UNS T11302 and diffusion behaviour for the TaN film on UNS S30400 steel. TaN films demonstrate their protection properties, which were evidenced by increase of the electrochemical properties compared with the substrate. The major corrosion damage of coatings is caused by defects, pores, droplets and pinholes that allow the electrolyte penetration through the films.

Corrosion protections of steels by TaN thin films.

The information related to corrosion behaviour of TaN films in a chloride solution is poor. This paper presents not only a completely electrochemical characterization, but also the surface analysis of the corroded samples.

The purpose of this paper is to compare the electrical conductivity and tribological properties of magnetron sputtered silver (Ag), copper (Cu) and aluminum (Al) thin films under conductive grease lubrication.

Three types of silver (Ag), copper (Cu) and aluminum (Al) thin films were prepared by magnetron sputtering. Current-carrying friction tests were carried out by a ball-on-plate reciprocating friction and wear tester. Scanning electron microscopy (SEM), X-ray diffraction (XRD) and energy dispersive X-ray spectroscopy (EDX) were used to observe and analyze the worn surface and cross-section morphology of the films.

Silver and Cu films exhibited good conductivity and tribological properties, which were mainly attributed to the synergy of the protective tribofilm generated by conductive grease, current-induced thermal effect and magnetron sputtered films effect. Al film was worn through. Large pitting storing lubricate were only found in Ag film. Cu film showed a similar surface uniformity with Ag film.

This study provides a reference for the design and application of conductive grease and investigates the current-carrying friction behaviors of magnetron sputtered films as electrical contact materials. The comparison of current-carrying friction behaviors of the three films was rarely covered in previous studies.