This page has only limited features, please log in for full access.
The current work aimed to characterize the morphology, chemical, and mechanical properties of Pt and PtTi thin films deposited via thermionic vacuum arc (TVA) method on glass and silicon substrates. The deposited thin films were characterized by means of a scanning electron microscope technique (SEM). The quantitative elemental microanalysis was done using energy-dispersive X-ray spectroscopy (EDS). The tribological properties were studied by a ball-on-disc tribometer, and the mechanical properties were measured using nanoindentation tests. The roughness, as well as the micro and nanoscale features, were characterized using atomic force microscopy (AFM) and transmission electron microscopy (TEM). The wettability of the deposited Pt and PtTi thin films was investigated by the surface free energy evaluation (SFE) method. The purpose of our study was to prove the potential applications of Pt-based thin films in fields, such as nanoelectronics, fuel cells, medicine, and materials science.
Sebastian Cozma; Rodica Vlǎdoiu; Aurelia Mandes; Virginia Dinca; Gabriel Prodan; Vilma Buršíková. Characterization of Platinum-Based Thin Films Deposited by Thermionic Vacuum Arc (TVA) Method. Materials 2020, 13, 1796 .
AMA StyleSebastian Cozma, Rodica Vlǎdoiu, Aurelia Mandes, Virginia Dinca, Gabriel Prodan, Vilma Buršíková. Characterization of Platinum-Based Thin Films Deposited by Thermionic Vacuum Arc (TVA) Method. Materials. 2020; 13 (7):1796.
Chicago/Turabian StyleSebastian Cozma; Rodica Vlǎdoiu; Aurelia Mandes; Virginia Dinca; Gabriel Prodan; Vilma Buršíková. 2020. "Characterization of Platinum-Based Thin Films Deposited by Thermionic Vacuum Arc (TVA) Method." Materials 13, no. 7: 1796.
This review summarizes the more-than-25-years of development of the so-called thermionic vacuum arc (TVA). TVA is an anodic arc discharge in vapors of the material to be deposited; the energy for its melting is delivered by means of a focused electron beam. The resulting material ions fall at the substrate where they form a well-adhesive layer; the ion energy is controllable. The deposited layers are, as a rule, free from droplets typical for cathodic arc deposition systems and the thermal stress of the substrates being coated is low. TVA is especially suitable for processing refractory metals, e.g., carbon or tungsten, however, in the course of time, various useful applications of this system originated. They include layers for fusion application, hard coatings, low-friction coatings, biomedical-applicable films, materials for optoelectronics, and for solid-state batteries. Apart from the diagnostic of the film properties, also the diagnostic of the TVA discharge itself as well as of the by TVA generated plasma was performed. The research and application of the TVA proceeds in broad international collaboration. At present, the TVA technology has found its firm place among the different procedures for thin film deposition.
Rodica Vladoiu; Milan Tichý; Aurelia Mandes; Virginia Dinca; Pavel Kudrna. Thermionic Vacuum Arc—A Versatile Technology for Thin Film Deposition and Its Applications. Coatings 2020, 10, 211 .
AMA StyleRodica Vladoiu, Milan Tichý, Aurelia Mandes, Virginia Dinca, Pavel Kudrna. Thermionic Vacuum Arc—A Versatile Technology for Thin Film Deposition and Its Applications. Coatings. 2020; 10 (3):211.
Chicago/Turabian StyleRodica Vladoiu; Milan Tichý; Aurelia Mandes; Virginia Dinca; Pavel Kudrna. 2020. "Thermionic Vacuum Arc—A Versatile Technology for Thin Film Deposition and Its Applications." Coatings 10, no. 3: 211.
C-Ti multilayer nanostructures were deposed by Thermionic Vacuum Arc (TVA) technology. The layers consisting of about 100nm Carbon base layer and seven 40nm alternatively Ti and C layers were deposed on Silicon substrates. On the other hand, in order to obtain C-Ti multilayer structures with variable thickness and different percentages in C and Ti of layers, a 20nm thick C layer was first deposed on Si substrate and then seven Ti-C layers, each of these having thickness of up to 40nm were deposed. To perform the successively layers with various thickness were changed the discharge parameters for C and Ti plasma sources to obtain the desirable thickness. By changing of substrate temperature between room temperature and 300°C and on the other hand the bias voltage up to -700V, different batches of samples were obtained for this study. To characterize properties of as prepared C-Ti multilayer structures were used Electron Microscopy techniques (TEM, STEM), Raman Spectroscopy, RBS techniques and tribological measurements. To characterize the electrical conductive properties, the electrical surface resistance versus temperature have been measured, and then the electrical conductivity. Using the Wiedemann-Frantz law was calculated the thermal conductivity.
Victor Ciupina; Cristian P Lungu; Rodica Vladoiu; Corneliu Porosnicu; Eugeniu Vasile; Virginia Nicolescu; Aurelia Mandes; Virginia Dinca-Balan; Ovidiu Cupsa. Carbon–titanium nanostructures: synthesis and characterization. Physica Scripta 2020, 95, 044012 .
AMA StyleVictor Ciupina, Cristian P Lungu, Rodica Vladoiu, Corneliu Porosnicu, Eugeniu Vasile, Virginia Nicolescu, Aurelia Mandes, Virginia Dinca-Balan, Ovidiu Cupsa. Carbon–titanium nanostructures: synthesis and characterization. Physica Scripta. 2020; 95 (4):044012.
Chicago/Turabian StyleVictor Ciupina; Cristian P Lungu; Rodica Vladoiu; Corneliu Porosnicu; Eugeniu Vasile; Virginia Nicolescu; Aurelia Mandes; Virginia Dinca-Balan; Ovidiu Cupsa. 2020. "Carbon–titanium nanostructures: synthesis and characterization." Physica Scripta 95, no. 4: 044012.
Titanium-based composites—titanium and silver (TiAg) and titanium and carbon (TiC)—were synthesized by the Thermionic Vacuum Arc (TVA) method on substrates especially for gear wheels and camshaft coating as mechanical components of irrigation pumps. The films were characterized by surface morphology, microstructure, and roughness through X-ray Diffraction (XRD), Atomic Force Microscopy (AFM), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), and Small-Angle Neutron Scattering (SANS). The silver (Ag) films crystallized into a cubic system with lattice a = 4.0833 Å at room temperature, indexed as cubic Ag group Fm3m. The crystallites were oriented in the [111] direction, and mean grain size was 111 = 265 Å. The TiC structure revealed a predominant cubic TiC phase, with a = 0.4098 as a lattice parameter determined by Cohen’s method. Average roughness (Ra) was 8 nm for the as-grown 170 nm thick TiAg film, and 1.8 nm for the as-grown 120 nm thick TiC film. Characteristic SANS contribution was detected from the TiAg layer deposited on a substrate of high-quality stainless steel with 0.45% carbon (OLC45) in the range of 0.015 Å−1 ≤ Q ≤ 0.4 Å−1, revealing the presence of sharp surfaces and an averaged triaxial ellipsoidal core-shell object.
Rodica Vladoiu; Aurelia Mandes; Virginia Dinca; Maria Balasoiu; Dmytro Soloviov; Vitalii Turchenko. Synthesis and Characterization of Complex Nanostructured Thin Films Based on Titanium for Industrial Applications. Materials 2020, 13, 399 .
AMA StyleRodica Vladoiu, Aurelia Mandes, Virginia Dinca, Maria Balasoiu, Dmytro Soloviov, Vitalii Turchenko. Synthesis and Characterization of Complex Nanostructured Thin Films Based on Titanium for Industrial Applications. Materials. 2020; 13 (2):399.
Chicago/Turabian StyleRodica Vladoiu; Aurelia Mandes; Virginia Dinca; Maria Balasoiu; Dmytro Soloviov; Vitalii Turchenko. 2020. "Synthesis and Characterization of Complex Nanostructured Thin Films Based on Titanium for Industrial Applications." Materials 13, no. 2: 399.
A series of the multicomponent thin films (binary: Ti-C; Ti-Ag and ternary: Ti-C-Ag; Ti-C-Al) were fabricated by Thermionic Vacuum Arc (TVA) technology in order to study the wear resistance and the anticorrosion properties. The effects of Ti amount on the microstructure, tribological and morphological properties were subsequently investigated. TVA is an original deposition method using a combination of anodic arc and electron gun systems for the growth of films. The samples were characterized using scanning electron microscope (SEM) and a transmission electron microscope (TEM) accompanied by selected area electron diffraction (SAED). Tribological properties were studied by a ball-on-disc tribometer in the dry regime and the wettability was assessed by measuring the contact angle with the See System apparatus. Wear Rate results indicate an improved sliding wear behavior for Ti-C-Ag: 1.31 × 10−7 mm3/N m (F = 2 N) compared to Ti-C-Al coating wear rate: 4.24 × 10−7 mm3/N m. On the other hand, by increasing the normal load to 3 N an increase to the wear rate was observed for Ti-C-Ag: 2.58 × 10−5 mm3 compared to 2.33 × 10−6 mm3 for Ti-C-Al coating.
Aurelia Mandes; Rodica Vladoiu; Gabriel Prodan; Virginia Dinca; Corneliu Porosnicu; Paul Dinca. The Properties of Binary and Ternary Ti Based Coatings Produced by Thermionic Vacuum Arc (TVA) Technology. Coatings 2018, 8, 114 .
AMA StyleAurelia Mandes, Rodica Vladoiu, Gabriel Prodan, Virginia Dinca, Corneliu Porosnicu, Paul Dinca. The Properties of Binary and Ternary Ti Based Coatings Produced by Thermionic Vacuum Arc (TVA) Technology. Coatings. 2018; 8 (3):114.
Chicago/Turabian StyleAurelia Mandes; Rodica Vladoiu; Gabriel Prodan; Virginia Dinca; Corneliu Porosnicu; Paul Dinca. 2018. "The Properties of Binary and Ternary Ti Based Coatings Produced by Thermionic Vacuum Arc (TVA) Technology." Coatings 8, no. 3: 114.
The synthesis of Ag, Mg and Si nanocrystalline, embedded in a hydrogen-free amorphous carbon (a-C) matrix, deposited by a high vacuum and free buffer gas technique, were investigated. The films with compact structures and extremely smooth surfaces were prepared using the thermionic vacuum arc method in one electron gun configuration, on glass and silicon substrates. The surface morphology and wettability of the obtained multifunctional thin films were investigated using transmission electron microscopy (TEM), scanning electron microscopy (SEM) and free surface energy (FSE) by See System. The results from the TEM measurements show how the Ag, Mg and Si interacted with carbon and the influence these materials have on the thin film structure formation and the grain size distribution. SEM correlated with EDX results reveal a very precise comparative study, regarding the quantity of the elements that morphed into carbides nanostructures. Also, the FSE results prove how different materials in combination with carbon can make changes to the surface properties.
Virginia Dinca-Balan; Rodica Vladoiu; Aurelia Mandes; Gabriel Prodan. Correlation study of nanocrystalline carbon doped thin films prepared by a thermionic vacuum arc deposition technique. Journal of Physics D: Applied Physics 2017, 50, 435305 .
AMA StyleVirginia Dinca-Balan, Rodica Vladoiu, Aurelia Mandes, Gabriel Prodan. Correlation study of nanocrystalline carbon doped thin films prepared by a thermionic vacuum arc deposition technique. Journal of Physics D: Applied Physics. 2017; 50 (43):435305.
Chicago/Turabian StyleVirginia Dinca-Balan; Rodica Vladoiu; Aurelia Mandes; Gabriel Prodan. 2017. "Correlation study of nanocrystalline carbon doped thin films prepared by a thermionic vacuum arc deposition technique." Journal of Physics D: Applied Physics 50, no. 43: 435305.
SiC single-layer or multi-layer on C used to improve the oxidation resistance and tribological properties of C have been obtained by Thermionic Vacuum Arc (TVA) method. The 200nm thickness carbon thin films was deposed on glass or Si substrate and then 100÷500 nm thickness SiC successively layers on carbon thin film was deposed. The microstructure and mechanical characteristics of as-prepared SiC coating were investigated by Transmission Electron Microscopy (TEM, STEM), Energy Dispersive X-Ray Spectroscopy (EDS), Electron Scattering Chemical Analysis (ESCA) and tribological techniques. Samples containing SiC single-layer or multi-layer coating on carbon were investigated up to 1000°C. The results of thermal treatments reveals the increase of oxidation resistance with increase of the number of SiC layers. The mechanism of oxidation protection is based on the reaction between SiC and elemental oxygen resulting SiO2 and CO. The tribological behavior of SiC coatings was evaluated with a tribometer with ball-on-disk configuration from CSM device with 6mm diameter sapphire ball, sliding speed in dry conditions being 0.2m/s, with normal contact loads of 0.5N, 1N, 1.5N and 2N, under unlubricated conditions. The friction coefficient on SiC was compared with the friction coefficient on uncoated carbon layer. Electrical surface resistance of SiC coating on carbon at different temperatures was measured comparing the potential drop on the sample with the potential drop on a series standard resistance in constant mode.
V. Ciupina; C. P. Lungu; R. Vladoiu; T-D. Epure; G. Prodan; C. Rosca; C. Porosnicu; I. Jepu; M. Belc; M. Prodan; I. M. Stanescu; C. Stefanov; M. Contulov; A. Mandes; V. Dinca; Eugeniu Vasile; V. Zarovschi; V. Nicolescu. SiC multi-layer protective coating on carbon obtained by thermionic vacuum arc method. Nanostructured Thin Films VI 2013, 8818, 881807 .
AMA StyleV. Ciupina, C. P. Lungu, R. Vladoiu, T-D. Epure, G. Prodan, C. Rosca, C. Porosnicu, I. Jepu, M. Belc, M. Prodan, I. M. Stanescu, C. Stefanov, M. Contulov, A. Mandes, V. Dinca, Eugeniu Vasile, V. Zarovschi, V. Nicolescu. SiC multi-layer protective coating on carbon obtained by thermionic vacuum arc method. Nanostructured Thin Films VI. 2013; 8818 ():881807.
Chicago/Turabian StyleV. Ciupina; C. P. Lungu; R. Vladoiu; T-D. Epure; G. Prodan; C. Rosca; C. Porosnicu; I. Jepu; M. Belc; M. Prodan; I. M. Stanescu; C. Stefanov; M. Contulov; A. Mandes; V. Dinca; Eugeniu Vasile; V. Zarovschi; V. Nicolescu. 2013. "SiC multi-layer protective coating on carbon obtained by thermionic vacuum arc method." Nanostructured Thin Films VI 8818, no. : 881807.
Nanostructured carbon materials have increasingly attracted the interest of the scientific community, because of their fascinating physical properties and potential applications in high-tech devices. In the current ITER design, the tiles made of carbon fiber composites (CFCs) are foreseen for the strike point zone and tungsten (W) for other parts of the divertor region. This choice is a compromise based mainly on experience with individual materials in many different tokamaks. Also Beryllium is the candidate material for the First Wall in ITER. In order to prepare nanostructured carbon-tungsten nanocomposite for the divertor part in fusion applications, the original method thermionic vacuum arc (TVA) was used in two electronic guns configuration. One of the main advantages of this technology is the bombardment of the growing thin film just by the ions of the depositing film. The nanostructured C-W and C-Be films were characterized by Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM) and Atomic Force Microscopy (AFM). The C-W films were identified as a nanocrystals complex (5 nm average diameter) surrounded by amorphous structures with a strong graphitization tendency, allowing the creating of adherent and wear resistant films. The C-Be films are polycrystalline with mean grain size about 15 nm. The friction coefficients (0.15 - 0.35) of the C-W coatings was decreased more than 3-5 times in comparison with the uncoated substrates proving excellent tribological properties. C-W nanocomposites coatings were designed to have excellent tribological properties while the structure is composed by nanocrystals complex surrounded by amorphous structures with a strong graphitization tendency, allowing the creating of adherent and wear resistant films.&updat
V. Ciupina; I. Morjan; C. P. Lungu; R. Vladoiu; G. Prodan; M. Prodan; V. Zarovschi; C. Porosnicu; I. M. Stanescu; M. Contulov; A. Mandes; V. Dinca; K. Sugiyama. Electron microscopy characterization of some carbon based nanostructures with application in divertors coatings from fusion reactor. SPIE NanoScience + Engineering 2011, 8104, 810411 .
AMA StyleV. Ciupina, I. Morjan, C. P. Lungu, R. Vladoiu, G. Prodan, M. Prodan, V. Zarovschi, C. Porosnicu, I. M. Stanescu, M. Contulov, A. Mandes, V. Dinca, K. Sugiyama. Electron microscopy characterization of some carbon based nanostructures with application in divertors coatings from fusion reactor. SPIE NanoScience + Engineering. 2011; 8104 ():810411.
Chicago/Turabian StyleV. Ciupina; I. Morjan; C. P. Lungu; R. Vladoiu; G. Prodan; M. Prodan; V. Zarovschi; C. Porosnicu; I. M. Stanescu; M. Contulov; A. Mandes; V. Dinca; K. Sugiyama. 2011. "Electron microscopy characterization of some carbon based nanostructures with application in divertors coatings from fusion reactor." SPIE NanoScience + Engineering 8104, no. : 810411.
Carbon thin films were synthesized using the original Thermionic Vacuum Arc (TVA) method. Mechanical properties were investigated using Micro Materials NanoTest 500 instrument using a NT Berkovich indenter. XPS provides a quantitative analysis of the surface composition and X‐ray generated Auger electron spectroscopy (XAES) performed by Thermoelectron ESCALAB 250 revealed information about the sp3:sp2 ratio of the carbon bondings. Structure and morphology was studied by Transmission Electron Microscope CM120ST, providing information on the grain size distribution of the crystalline diamond structures (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
V. Ciupina; J. Sullivan; S. Saied; R. Vladoiu; G. Prodan; I.M. Oancea-Stanescu; A. Mandes; M. Contulov; V. Dinca; M. Prodan; D. Manole. Synthesis and Characterization of Some Carbon Based Nanostructures. Contributions to Plasma Physics 2010, 51, 546 -553.
AMA StyleV. Ciupina, J. Sullivan, S. Saied, R. Vladoiu, G. Prodan, I.M. Oancea-Stanescu, A. Mandes, M. Contulov, V. Dinca, M. Prodan, D. Manole. Synthesis and Characterization of Some Carbon Based Nanostructures. Contributions to Plasma Physics. 2010; 51 (6):546-553.
Chicago/Turabian StyleV. Ciupina; J. Sullivan; S. Saied; R. Vladoiu; G. Prodan; I.M. Oancea-Stanescu; A. Mandes; M. Contulov; V. Dinca; M. Prodan; D. Manole. 2010. "Synthesis and Characterization of Some Carbon Based Nanostructures." Contributions to Plasma Physics 51, no. 6: 546-553.
The aim of this paper is concerned with the surface energy evaluation by contact angle measurements of DLC films deposited by thermionic vacuum arc (TVA) on different substrates: glass plate, zinc foil, stainless steel and alumina foil. TVA is an original method based on a combination of the evaporation by electron bombardment and anodic arc. The evaluation of the surface free energy has been carried out by surface energy evaluation system (SEE System). The influence of the experimental conditions is also investigated.
R. Vladoiu; V. Dinca; G. Musa. Surface energy evaluation of unhydrogenated DLC thin film deposited by thermionic vacuum arc (TVA) method. The European Physical Journal D 2009, 54, 433 -437.
AMA StyleR. Vladoiu, V. Dinca, G. Musa. Surface energy evaluation of unhydrogenated DLC thin film deposited by thermionic vacuum arc (TVA) method. The European Physical Journal D. 2009; 54 (2):433-437.
Chicago/Turabian StyleR. Vladoiu; V. Dinca; G. Musa. 2009. "Surface energy evaluation of unhydrogenated DLC thin film deposited by thermionic vacuum arc (TVA) method." The European Physical Journal D 54, no. 2: 433-437.