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ZrN coatings have been grown in an rf sputtering deposition chamber, using different ratios of Ar/N 2 (5/1, 5/5, 1/5) in the reactive gas flow. After deposition, the coatings were thermally treated in a 500°C oxygen atmosphere, in order to test the thermal stability of the layers or the oxynitride formation. The chemical composition, surface roughness and structural, mechanical and tribological...
The behaviour of the crystalline properties of ZrO 2 films prepared by electron beam physical vapour deposition (EB-PVD) is investigated as a function of their deposition rates. In this paper, the conditions for the preparation of tetragonal zirconia from yttria stabilized zirconia and from monoclinic powder as starting materials are reported. The variation of the crystallite size as a function...
Multilayer systems at nanometre scale have been applied as spectroscopic elements for wavelengths >1nm and optical reflection systems in the short-wavelength region (<100nm). Main requirements are a high optical contrast for the multilayer components in the wavelength region of application and a density profile with sharp interfaces between the components. Two sources are responsible for interface...
A photoluminescence (PL) study at room temperature was accomplished as a complement to well-established structural and morphological characterization techniques such as μ-Raman, FTIR, XRD, XPS or SEM. Considering the wide electronic band gap of pure diamond (5.45eV), the near ultraviolet excitation (325nm) from an HeCd laser source was selected. The observed nanocrystalline diamond (NCD) and microcrystalline...
A mechanical characterization study of the whole range (ZrO 2 ) 1−x –(Y 2 O 3 ) x system is presented for thin film samples. Films have been prepared by Electron Beam Physical Vapour Deposition (EB-PVD) on Si(100) substrates. The mechanical characterization, obtained from nanoindentation and Brillouin Light scattering (BLS) techniques, shows a monotonous...
In the present study, hot filament chemical vapour deposition technique was used to grow diamond films from nanometric to microcrystalline grain sizes. Their adhesion levels to a silicon nitride ceramic were compared after Brale tip indentation testing. The best behaviour was attained by the microcrystalline diamond (MCD) grade due to its higher crystallinity and superior hardness. In contrast, nanocrystalline...
W–S–C films were deposited by magnetron sputtering in an Ar atmosphere with a Ti interlayer. A carbon target with several pellets of WS 2 incrusted in the zone of the preferential erosion was used. The number of pellets was changed to modify the carbon content in the films, which varied from 29 up to 70at%. Doping W–S films with carbon led to a substantial increase of the hardness in the range...
Multilayered structures with nanometric periods and nanocomposite materials are probably the most promising alternatives to improve the properties of conventional coatings used for mechanical applications. Most of the multilayered structures referred to in the literature present mechanical properties that surpass those of their individual materials: increase of hardness, elastic limit and toughness,...
The deposition at low energies of Cu and Au nanoclusters, respectively, on Au(001) and Cu(001) substrates is studied by constant-temperature molecular-dynamics simulations. Initially, clusters had icosahedral or Wulff shapes and their number of atoms ranged between 13 and 1289. The deposition energy and the temperature were, respectively, 17meV/atom and 300K. Atomic interactions are mimicked by a...
CdS thin films grown on ITO/glass substrates by using chemical bath (CB) were boron-implanted employing 100keV beam of boron ions (B + ) with fluences in the range 1.0×10 15 –1.0×10 16 ions/cm 2 . The B doping was successfully carried out, as was proved by the major carrier density introduced in the range 0.8×10 18 –5.4×10 18 cm −3 , which was...
TiN coatings can be obtained in a relatively wide range of compositions around stoichiometry. Changing the stoichiometry around the 1:1 composition broadens the spectrum of colors and can modify the mechanical properties as compared with those of stoichiometric TiN. In this work, we present the deposition of TiN coatings by using a metallic Ti cathode and varying the nitrogen partial pressure in a...
Novel CrTiAlN multilayered nanocomposite thin films have been developed. They consist of alternating CrN and TiAlN layers of 10–12nm individual thickness, up to a total thickness of 1–3μm. These coatings were grown on WC-Co insets and high-speed steel samples by simultaneous arc evaporation (physical vapour deposition, PVD) of pure Cr and Ti-Al alloy targets. Wear resistance of these coatings was...
Rhodamine 6G (Rh6G)-doped amorphous titanium thin films were prepared by the sol–gel technique. The films were grown at room temperature (RT) and supported on silica-glass substrates, which were previously chemically activated. Photoluminescence (PL) spectra were registered at RT by using as photo excitation the 325nm He–Cd line. The PL versus the photon energy emission curves peak at around 3.2eV,...
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