PVD Method Research Articles

A parametric study of low friction coating by PVD method on the spiralock female thread for ITER application

The hard lubrication is defined that the thin films are deposited by radio-frequency magnetron sputtering from the target material on substrate in order to improve their desired properties such as hardness, friction and wear resistance. Especially, the MoS2 coating can be used in high vacuum and aerospace environments for lubrication purposes, which low friction is required. Unlike fluid lubrications, MoS2 is suitable for use in a vacuum environment because it has low outgassing pressure and lack of migration. For this reason, the sputtered MoS2 coating is primarily considered as low friction / anti-seize coating method of the ITER blanket central bolt insert. A magnetron sputtering process, which permits friction coefficient and durability of the MoS2 coating, suites to coat precision mechanical component with its exquisitely thin thickness. However, the coating on the spiralock female thread of blanket central bolt inserts is difficult to have uniform coating deposition due to its shadow effect. Therefore, it is necessary for understanding the parameters and effects of sputtering process to achieve the uniform coating having the required friction coefficient less than 0.05. Details of parametric study with various sputtering conditions on the simple disk and spiralock female thread to reach required friction coefficient and uniform coating thickness, are presented in this paper.

Effect of carbon content on resistance to cavitation erosion of Cr-C coatings deposited by Arc PVD method

The aim of the study is a comparative analysis of effect of the carbon content in the range from 2 to 25 at.% on the resistance to cavitation erosion of Cr-C coated samples by means of the rotating disk method. The effect of carbon concentration in the range from 2 to 25 at % on the structure, properties and cavitation resistance of Cr-C vacuum-arc coatings deposited in argon with toluene at a pressure of 0.08 to 0.23 Pa on 12Cr18Ni10Ti stainless steel samples has been studied. It has been established that the application of coatings leads to a decrease in the rate of cavitation erosion of steel from 4 to 6 times. Chromium coatings with a two-phase structure containing carbide Cp7C3 show maximum durability.

Modifying Coatings for Medical Implants Made of Titanium Alloys

This review considered various methods for depositing special modifying coatings on medical implants made of titanium alloys including techniques such as electrochemical deposition, sol–gel process, atmospheric plasma deposition, and PVD methods (magnetron sputtering and vacuum arc deposition). The rationale is provided for the use of modifying coatings to improve the performance efficiency of implants. The concept of a functional multilayer coating designed for products operating in the human body environment is proposed. The advantages and disadvantages of various methods for depositing coatings are considered based on the possibility of their use for obtaining modifying coatings for medical purposes deposited on a titanium alloy base.

Cu Metallization of Al2O3 Ceramic by Coating Deposition from Cooled- and Hot-Target Magnetrons

We examined the feasibility of alumina substrate metallization by magnetron deposition of copper coatings with thickness of several tens µm for its prospective applications in production of ceramic PCBs and packaging. The films were prepared in magnetron sputtering systems with cooled and thermally insulated (hot) targets. Substrates with different geometries were used, including those with through-holes. Thickness, adhesive properties, and electrical resistivity of produced coatings were analyzed. If the film thickness exceeded ~20 µm, we observed its systematic delamination, unless the dedicated CuxOy sub-layer of was introduced between the substrate and the main Cu film. Intermediate copper oxide films were investigated separately by SEM, EDS, and XRD methods, and deposition conditions for predominant growth of favorable tenorite CuO were determined. Prepared composite two-layer CuO + Cu coatings with total thickness of ~100 µm demonstrated good adhesion to alumina substrates in scratch-testing and performed much better than Cu-only films both in soldering and thermal cycling tests. We discuss an approach for constructing a reliable metallizing coating by plasma-assisted PVD methods that could be beneficial for complex-shaped ceramic PCBs and packaging.

Influence of Heat Treatment on Corrosion Resistance of Sn/Mg Films Formed by PVD Method on Hot-Dip Galvanized Steel

Double layers composed of Sn and Mg, each 0.8 μm thick, were fabricated on a hot-dip galvanized steel (8.4 μm) sheet using DC magnetron sputtering and post-annealing processes. With an increase in temperature, the surface morphologies were agglomerated with each other. Additionally, Sn/Mg mixture sites, including an intermetallic compound of Mg2Sn, were formed at 190 °C and locally clustered at 220 °C. In the salt-spray test, the corrosion resistance of the Sn/Mg film prepared at 190 °C was 960 h, which is longer than that at non-heat for 528 h or 220 °C for 480 h. In the polarization test, the Sn/Mg film formed at 190 °C displayed a lower corrosion current density of 1.07 μA/cm2 and potential of 1.62 V/SSCE than those at non-heat or 220 °C.

Investigation of the Influence of Anti-Wear Coatings on the Surface Quality and Dimensional Accuracy during Finish Turning of the Inconel 718 Alloy.

This piece of work deals with the influence assessment of the kind of coating of the cutting inserts and their wear on the dimensional accuracy and the top layer microstructure and roughness of the surface machined with constant cutting parameters vc = 85 m/min, f = 0.14 mm/obr and ap = 0.2 mm. The tests were performed on shafts made of Inconel 718 material under the conditions of finish turning, requiring a tool life of more than 20 min. The cutting inserts of identical geometry made of fine-grained carbide covered with coatings were applied by the PVD and CVD method. The values of the obtained diameter dimensions were assessed in reference to the assumed ones, as well as the values of the surface roughness and stereometry and the microstructure of the top layer. The nature and mechanisms of edge wear and its value expressed by the VBC parameter were also assessed. It was determined in the tests that the machined surface quality defined by the Ra and Sa roughness parameters and the dimensional accuracy were influenced not only by the coating microhardness but also by the method of applying the given coating. The lowest values of the tested roughness parameters were observed for the surface machined with an edge, with the S205 coating applied by the CVD method, which was characterized by the lowest microhardness. The edge with this coating also showed the lowest wear, defined by the VBC parameter, which translated into dimensional accuracy. Furthermore, the edge with the S205 coating also provided the best results with regard to the surface layer microstructure. The least favorable results, both in terms of dimensional accuracy and surface roughness, were obtained for the surface machined with a 1115-PVD-coated edge. The highest wear value was also recorded for this edge.

Influence of coatings based on Zr and Ti on the wear resistance of cemented carbide tools when turning transport machines’ parts from structural steels

The influence of coatings based on titanium carbide and zirconium carbide, obtained by PVD method, on cutting tool wear resistance under conditions of the longitudinal turning of transport machines’ parts of steel 45 and stainless steel 12H18N10T by inserts of hard alloy grade T15K6 was investigated. It has been experimentally established that the presence and composition of the coating on the working surfaces of the tool in most cases contributes to a significant reduction in the intensity of wear of cemented carbide inserts. When turning stainless steel 12H18N10T, the best result was demonstrated by the coating ZrN + (Ti–Zr) N + TiN, which provided not only the minimum intensity of wear, but also the expansion of the range of optimal cutting speeds. When machining structural steel 45, the maximum reduction in the wear intensity of the cutting inserts was observed with the use of a single-layer TiN coating and a (Ti,Zr)N coating.

Improvement of Wear Resistance in Toothed Harrows Coated with HVOF and PVD Methods

Improvement of Wear Resistance in Toothed Harrows Coated with HVOF and PVD Methods

Programmable Nucleation and Growth of Ultrathin Tellurium Nanowires via a Pulsed Physical Vapor Deposition Design

AbstractPhysical vapor deposition (PVD) methods have been widely employed for high‐quality crystal growth and thin‐film deposition in semiconductor electronics. However, the fabrication of emerging low dimensional nanostructures is hitherto challenging in conventional PVD systems due to their large thermal mass and near‐continuous operation which hinder flexible control of the nucleation and growth events. Herein, a pulsed PVD method is reported that features finely controllable temperature and heating time (down to milliseconds), which enables programming of the vapor supersaturation and decoupling of nucleation and growth events. Take tellurium as an example, the pulsed PVD allows transient source vaporization (≈1000 °C, 30 ms) for burst nucleation, followed by relatively low‐temperature volatilization (≈600 °C, 5 min) for steady‐state growth with well‐suppressed random nucleation. As a result, uniform and high‐density tellurium nanowires are obtained at the ultrathin thickness of sub‐10 nm and length >10 µm, which is in sharp contrast to the randomly formed nanostructures in conventional PVD. When used in the field‐effect transistor, the thin tellurium nanowires display a high on‐off ratio of >104 and hole mobility of ≈40 cm2 V−1 s−1, showing the potential for high‐performance electronics. Pulsed PVD therefore enables to flexibly program and finely tailor the nucleation and growth events during vapor phase deposition, which are otherwise impossible in conventional PVD.

Investigation of Ti/Al2O3 + TiO2 and Ti + TiO2/Al2O3 + TiO2 hybrid coatings as protection of ultra-light Mg–(Li)–Al–RE alloys against corrosion

Low corrosion resistance is a significant problem of magnesium alloys, particularly ultra-light magnesium-lithium alloys. Surface treatment is one way to improve their corrosion resistance. The paper presents the results of tests of Ti/Al2O3 + TiO2 and Ti + TiO2/Al2O3 + TiO2 coatings obtained in a hybrid process combining PVD and ALD methods and ALD coating of Al2O3 + TiO2 type obtained on AE42 (Mg–4Li–2RE) and LAE442 (Mg–4Li–4Al–2RE). Structural studies were performed using scanning and transmission electron microscopy (SEM and TEM), atomic force microscopy and EDS and XPS spectroscopic methods. Potentiodynamic tests and electrochemical impedance spectroscopy EIS in 0.05 M NaCl solution were performed to determine the electrochemical properties of the tested materials. Moreover, tests of surface wettability and tribological properties using the ball-on-disc method were performed. Based on the analysis of anodic polarisation curves and Tafel analysis, it was found that the Ti + TiO2/Al2O3 + TiO2 coating showed the best potentiodynamic properties on both substrates. In particular, on the magnesium-lithium substrate, the value of the polarisation resistance of this hybrid coating is Rpol = 14 × 103 Ω × cm2, and the value of the corrosion current is jcorr = 0.4 µA/cm2. For the uncoated LAE442 substrate, the polarisation resistance is Rpol = 1.05 × 103 Ω × cm2, and the corrosion current value is jcorr = 5.49 µA/cm2. This improvement is due to the synergistic effect of the combined PVD and ALD technologies. The study confirmed the impact of hybrid coatings on improving the anti-corrosion and tribological properties of ultra-light magnesium alloys.

Preparation and Photocatalytic Activities of TiO2-Based Composite Catalysts

While modern industry has contributed to the prosperity of an increasingly urbanized society, it has also led to serious pollution problems, with discharged wastewater and exhaust gases causing significant environmental harm. Titanium dioxide (TiO2), which is an excellent photocatalyst, has received extensive attention because it is inexpensive and able to photocatalytically degrade pollutants in an environmentally friendly manner. TiO2 has many advantages, including high chemical stability, low toxicity, low operating costs, and environmental friendliness. TiO2 is an N-order semiconductor material with a bandgap of 3.2 eV. Only when the wavelength of ultraviolet light is less than or equal to 387.5 nm, the valence band electrons can obtain the energy of the photon and pass through the conduction band to form photoelectrons, meanwhile the valence band forms a photogenerated hole. And light in other wavelength regions does not excite this photogenerated electrons. The most common methods used to improve the photocatalytic efficiency of TiO2 involve increasing its photoresponse range and reducing photogenerated-carrier coupling. The morphology, size, and structure of a heterojunction can be altered through element doping, leading to improved photocatalytic efficiency. Mainstream methods for preparing TiO2 are reviewed in this paper, with several excellent preparation schemes for improving the photocatalytic efficiency of TiO2 introduced. TiO2 is mainly prepared using sol-gel, solvothermal, hydrothermal, anodic oxidation, microwave-assisted, CVD and PVD methods, and TiO2 nanoparticles with excellent photocatalytic properties can also be prepared. Ti-containing materials are widely used to purify harmful gases, as well as contaminants from building materials, coatings, and daily necessities. Therefore, the preparation and applications of titanium materials have become globally popular research topics.

Nano-Ag Particles Embedded in C-Matrix: Preparation, Properties and Application in Cell Metabolism.

The application of nano-Ag grains as antiviral and antibacterial materials is widely known since ancient times. The problem is the toxicity of the bulk or big-size grain materials. It is known that nano-sized silver grains affect human and animal cells in some medical treatments. The aim of this study is to investigate the influence of nano-Ag grains embedded in a carbonaceous matrix on cytotoxicity, genotoxicity in fibroblasts, and mutagenicity. The nanocomposite film is composed of silver nanograins embedded in a carbonaceous matrix and it was obtained via the PVD method by deposition from two separated sources of fullerenes and silver acetate powders. This method allows for the preparation of material in the form of a film or powder, in which Ag nanograins are stabilized by a carbon network. The structure and morphology of this material were studied using SEM/EDX, XRD, and Raman spectroscopy. The toxicology studies were performed for various types of the material differing in the size of Ag nanograins. Furthermore, it was found that these properties, such as cell viability, genotoxicity, and mutagenicity, depend on Ag grain size.

TRIBOLOGICAL PROPERTIES OF THE FRICTION PAIR WITH a-C:H COATING UNDER THE CONDITIONS OF LUBRICATION WITH 10W40 BIODEGRADABLE ENGINE OIL

The present study discusses the influence of an a-C:H coating on the tribological parameters of sliding pairs under mixed friction. Using the PVD method, the a-C:H coating was formed on specimens made from AISI 4337 steel. The sliding friction and wear process was carried out on the pairs of AISI 4337 steel and SAE- 48 bearing alloy, which were lubricated with 10W40 biodegradable engine oil. The investigation showed significant differences in the friction coefficient and temperature in the tested pairs with the steel surface layer and the a-C:H coating. In the friction pairs with the a-C:H coating, the tested parameters of friction were higher than in pairs with the steel surface layer. The pairs with the a-C:H coating showed more intensive wear of the SAE-48 bearing alloy than those with a steel surface. The surface layer used in a friction pair leads to the deterioration of the lubricating properties of engine oil and reduces its resistance to scuffing.

Effect of Si Content on Deposition and High-Temperature Oxidation of Al-Si Coatings Obtained by Magnetron Sputtering PVD Method

Intermetallic Al-Si-based coatings can greatly increase the oxidation resistance of γ-TiAl alloys. However, the effects of the Si addition are not fully understood. Therefore, it is difficult to determine the Si content that is optimal for oxidation resistance. Therefore, pure Al and several Al-Si coatings with varying Si contents between 1 and 81 at.% were studied. The coatings were produced using a combinatorial magnetron sputtering process. Scanning electron microscopy and energy dispersive X-ray spectroscopy were used for structure and chemical analysis. The phases were identified by X-ray diffraction. Cyclic oxidation tests at 900 °C were conducted up to 5000 cycles of 1 h each and subsequently evaluated by thermogravimetric analysis. Si addition in the range of 1 to 12 at.% did not deteriorate the oxidation resistance compared to a pure Al coating up for 1000 cycles (1 h) of oxidation at 900 °C, while higher Si contents led to a high mass gain. For oxidation times up to 5000 cycles (1 h), a sufficient thickness of the coatings is crucial for good oxidation resistance. The main effect of Si addition is to enhance the transformation speed of the deposited Al and Si to the high temperature stable Ti(Al,Si)3 phase during the heat treatment. Si additions of up to 12 at.% led to increased initial mass gains and a decrease in the oxidation rates during subsequent exposures compared to pure Al coatings.

Synthetic 2D tellurium nanosheets with intense TE wave polarization absorption by employing the PVD method

Synthetic 2D tellurium nanosheets with intense TE wave polarization absorption by employing the PVD method

Improvement of tribological performance of AZ31 biodegradable alloy by TiN-based PVD coatings

Making Mg and its alloys suitable for use as biodegradable implant material was the subject of innovative studies in this field. In this study, it was aimed to improve the surface properties of the AZ31 alloy and to increase the wear performance as the first step to improve its biodegradable character. In this context, AlTiN and Ag doped TiN films were grown on the surface by PVD method. In order to correlate wear performance with biological effects, three different solutions and two wear loads were used for liquid media experiments in terms of in vitro simulation of body fluid. An extensive post-wear performance data was collected for in vitro analysis of biodegradation.

Influence of the Addition of the Elements Ti and Cr on the Structure, and Mechanical and Tribological Properties of AlSiN Coatings

The influence of Al/Ti and Al/Cr ratios on the structural, mechanical and tribological properties of AlTiSiN and AlCrSiN coatings, deposited by the cathodic arc evaporation PVD method at a temperature of 400°C, was investigated. The remains of the original AlSiN hexagonal phase were observed in the obtained coatings as well as the crystallites of cubic TiN and CrN, respectively. XPS analysis assumes the presence of a substoichiometric SiN. The addition of 11 at.% Ti or 13 at.% Cr in AlSiN led to an increase in both the coating’s resistance to plastic deformation and the plasticity index. The addition of 13 at.% and 24 at.% Cr to the AlSiN coating structure resulted in a decrease in the average coefficient of friction with 18% and 36% against a counterpart of Al2O3, respectively, and with 36% for both concentration against steel ball counterpart. The addition of Ti have no influence on the values of the coefficient of friction at using ceramic counterpart, while at steel counterpart decreased it up to 30%. Both element change the abrasion effect of the coating.Keywords:AlCrSiN; AlTiSiN;Cathodic Arc Deposition; Tribological Behaviour; Abrasion Resistance; Nanoindentation

Abrasive wear behaviour of nano-TiN coated AISI D3 tool steel

In this study, the effect of nano-TiN layer obtained by PVD method on tribological behaviour of X210Cr12 (1.2080, AISI D3) cold work tool steel was investigated. Coating process was carried out by cathodic-arc PVD method using 200 V voltage, 350 °C temperature, 4x10-4 mbar pressure, and 50 A current application conditions. The characterization of the coating was carried out by FESEM and SEM-EDS analysis. The coated and uncoated samples were subjected to abrasive wear test against to 220 mesh sandpaper under 3 different loads (5, 10, and 20 N). The tests were applied at three different sliding distances (100 m, 200 m, and 600 m) keeping the sliding speed as constant at 2,6 m/s. 
 For uncoated samples, while the applied load increased from 5 N to 20 N, the approximate wear loss increased by 10 and 8.5 times, respectively. The approximate wear loss increased by 2.2 and 12.2 times, respectively in nano-TiN coated samples. When compared to the coated and uncoated samples, the wear loss values obtained in the coated samples at sliding distances of 100 m and 200 m differed greatly from uncoated samples, under same conditions almost 100%. However, when the sliding distance reached 600 m, the gap started to close and the gap decreased to 30%.

RELIABILITY OF VEHICLE VEHICLES AT THE STAGE OF PREPARATION

The reduction of the duration of running-in is most strongly influenced by the speed-power and technological factors. It was experimentally established that at specific loads of 0.15 – 3 MPa and tribopair velocities of 6 – 40 m/min (0.1 - 0.66 m/sec) and methods of surface hardening and surface hardening, nitrocementation and ion-plasma thermocyclic nitriding, a combination of speed, power and technological factors can reduce the running-in process by 1.5 - 2 times.A mathematical model has been developed that combines the components of these factors for the running-in process in relation to the reduction of the latter.The stand for experimental research of the tribotechnical system, which consists of an automatic gearbox with a magnetic brake, a power supply, a control panel and a PC, has been upgraded. The firmware is written in the Python programming language.For further research in the chosen direction, the application of wear-resistant coatings with a thickness of 3 … 10 μm by PVD methods containing nitrides and carbides is promising.

Creation of magnetic thin film integrated optical non-reciprocal element using supersonic free jet PVD method

Professor Hideki Yokoi, Department of Electronic Engineering, Shibaura Institute of Technology, Japan, is focused on developing a magneto-optical waveguide with a semiconductor waveguide layer. He and his team are using wafer bonding technology and a new film forming method called the supersonic free jet PVD method to create an optical waveguide with an arbitrary layer structure. The research of Yokoi and the team is paving the way for the possibility to easily manufacture an optical waveguide of any layer structure, which will lead to the development of magneto-optical waveguides for optical nonreciprocal elements, optical integrated circuits that will integrate the optical elements with various functions, and optoelectronic integrated circuits. In addition, by replacing electrical wiring with optical wiring, there will be a suppression of heat loss and reduction of power consumption, reaping environmental benefits. Yokoi and the team are working alongside the International Research Centre for Green Electronics (IRCGE), which aims to contribute to green innovation. Ultimately, Yokoi hopes his findings will have benefits that will expand beyond the field of optical communications, including a positive environmental impact through reduced power consumption.