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- Magnetron sputtering (1)
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- TiZrN film (1)
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Magnetron sputtering is one of the most commonly used deposition techniques, which has received considerable attention in industrial applications. In particular, owing to its compatibility with conventional fabrication processes, it can produce and fabricate high-quality dense thin films of a wide range of materials. In the present study, nitrogen (N) was combined with pure vanadium in order to form binary nitride to improve its mechanical and tribological performance. To evaluate the influence of nitrogen on the structure of the as-deposited vanadium nitride (VN) coatings, the following techniques were used: XPS, XRD, SEM, AFM and optical profilometry. The residual stresses were determined by the curvature method using Stoney’s formula. The hardness and Young’s modulus were obtained by nanoindentation measurements. The friction behavior and wear characteristics of the films were evaluated by using a ball-on-disk tribometer. The obtained results showed that the N/V ratio increased with increasing the N2 flow rate while the deposition rate decreased. The preferred orientation was changed from (200) to (111) as the N2 flow rate increased with the presence of V–N and V–O binding energies as confirmed by XPS analysis. The nitrogen addition resulted in a columnar morphology and a fine structure with fine surface roughness. The VN thin film containing 49.5 at.% of nitrogen showed the best performance: highest mechanical properties (hardness = 25 GPa), lowest friction coefficient (μ = 0.37) and lowest wear rate (Ws = 2.72 × 10−5 mm3N−1 m−1). A good correlation between the film microstructure, crystallite size, residual stress and mechanical and tribological properties was observed.
TiZrN thin films were deposited on Si (100) wafers and XC100 steel substrates by reactive R.f. magnetron sputtering using titanium and zirconium targets in an Ar-N2 mixture atmosphere to evaluate the effect of varying Zr content (0 to 22.2 at.%), on the film structure, surface wettability, hardness and wear resistance. The presence of different phases such as TiN, ZrN, and ZrO2 were confirmed by XRD analysis. Results showed that, the lattice parameter and film thickness increased while the crystallite size and average roughness decreased with increasing Zr content. Total surface energy between the film surface and testing liquids decreased with the addition of Zr. TiZrN film containing 18.3 at.% of Zr showed the lowest surface energy of 38.7 mN/m, indicating its hydrophobicity. The nanoindentation measurements, friction and wear tests showed that the TiZrN thin film containing 18.3 at.% of Zr had the best tribo-mechanical performance. The TiZrN (18.3 at.% Zr) film exhibited the lowest friction coefficient (0.31), and the lowest wear rate (6.65 × 10−5 mm3/Nm), which corresponds to the highest H/E ∼ 0.139, and H3/E2 ∼ 0.49 GPa ratios. The improvement in the tribo-mechanical properties is attributed to the solid solution strengthening due to the incorporation of Zr atoms in TiN system, which results in the highest hardness of 25 GPa for TiZrN (18.3 at.% Zr) film.