@misc{FouziaFellahHeziletal., author = {Fouzia, Hammadi and Fellah, Mamoun and Hezil, Naouel and Aissani, Linda and Mimanne, Goussem and Mechachti, Said and Samad, Mohammed Abdul and Montagne, Alex and Iost, Alain and Weiß, Sabine and Obrosov, Aleksei}, title = {The effect of milling time on the microstructure and mechanical properties of Ti-6Al-4Fe alloys}, series = {Materials Today Communications}, volume = {27}, journal = {Materials Today Communications}, issn = {2352-4928}, doi = {10.1016/j.mtcomm.2021.102428}, pages = {11}, abstract = {Replacement of toxic and expensive vanadium (V) in medical grade titanium alloys with cheaper and non-toxic elements such as iron (Fe) or niobium (Nb), is an important step forward in developing safer and less expensive biomaterials. Evaluating the effect of different process parameters such as the milling time on the properties of these newly developed alloys helps in understanding and controlling their behavior. Hence, in this study, the influence of ball-milling duration (2, 6, 8, 12 and 18 h) on crystalline structure, phase evolution, densification, and mechanical characteristics of biomedical nanocrystalline Ti-6Al-4Fe (wt. \%) alloys is investigated. X-ray diffraction (XRD) confirmed that after 6 h of milling, aluminum (Al) and Fe completely dissolved into Ti matrix to form a solid solution of Ti (Al, Fe). XRD further revealed that the crystallite size decreased from 56 to 30 nm and the micro-strain increased with an increase in milling time. A decrease in porosity along with an increase in density is also observed for the alloys with increasing milling time. Moreover, the values of porosity obtained for the developed Ti-6Al-4Fe alloys ranged from 1 to 12 \%, which is comparable to the porosity of one of the cortical bones making it a potential candidate for bone replacements. Microhardness measurements showed that the hardness of the Ti-6Al-4Fe alloys was greater than the hardness of the conventional Ti-6Al-4V alloys. It was observed that the Ti-6Al-4Fe alloy fabricated with the powders milled for 2 h showed the lowest value of Young's Modulus. Milling time also had a significant effect on the surface roughness of the alloy samples, which showed a decreasing trend with increasing milling times.}, language = {en} } @misc{AissaniFellahChadlietal., author = {Aissani, Linda and Fellah, Mamoun and Chadli, Abdel Hakim and Samad, Mohammed Abdul and Cheriet, Abderrahmane and Salhi, Faiza and Nouveau, Corinne and Weiß, Sabine and Obrosov, Aleksei and Alhussein, Akram}, title = {Investigating the effect of nitrogen on the structural and tribo-mechanical behavior of vanadium nitride thin films deposited using R.F. magnetron sputtering}, series = {Journal of Materials Science}, volume = {56}, journal = {Journal of Materials Science}, number = {30}, issn = {1573-4803}, doi = {10.1007/s10853-021-06393-0}, pages = {17319 -- 17336}, abstract = {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.}, language = {en} } @misc{AissaniFellahBelgrouneetal., author = {Aissani, Linda and Fellah, Mamoun and Belgroune, Ahlam and Obrosov, Aleksei and Samad, Mohammed Abdul and Alhussein, Akram}, title = {Effect of O2 flow rate on the structure, wettability and tribo-mechanical behaviour of Zr-O-N thin films}, series = {Surfaces and Interfaces}, volume = {26}, journal = {Surfaces and Interfaces}, issn = {2468-0230}, doi = {10.1016/j.surfin.2021.101441}, pages = {33}, abstract = {Structural and tribo-mechanical properties of Zr-O-N films deposited by reactive magnetron sputtering in a mixture of Ar (flow rate = 80 sccm), N2 (flow rate = 20 sccm) and O2 with a varying flow rate of 0 to 12 sccm were investigated. The films were characterized using scanning electron microscopy, energy dispersive x-ray analysis, atomic force microscopy, nanoindentation and wear tests. Oxygen content have a significant effect on the microstructure, wettability, tribo-mechanical properties of Zr-O-N films. The Zr-O-N films showed a dense structure with a mixture of zirconium oxides and nitrides and the preferred orientation changed from (111) ZrN to (200) ZrN with increasing O2 flow rate. The ZrON film, deposited at an oxygen flow rate of 10 sccm exhibited the highest contact angle (147°), the highest hardness (27.1 GPa), the lowest friction coefficient (0.36) and the lowest wear rate (5.8 × 10-7 mm3.Nm-1). The improvement in the tribological performance of the ZrON film deposited at 10 sccm is attributed to the improved hardness and increased H/E and H3/E2 ratios, due to the formation of a hard solid solution by the diffusion of oxygen.}, language = {en} } @misc{SalhiAissaniFellahetal., author = {Salhi, Faiza and Aissani, Linda and Fellah, Mamoun and Chadli, Abdel Hakim and Cheriet, Abderrahmane and Belgroune, Ahlam and Nouveau, Corinne and Obrosov, Aleksei and Samad, Mohammed Abdul and Alhussein, Akram}, title = {Experimental investigation of structural, wetting, mechanical and Tribological properties of TiZrN thin films deposited by magnetron sputtering}, series = {Surfaces and Interfaces}, volume = {27}, journal = {Surfaces and Interfaces}, issn = {2468-0230}, doi = {10.1016/j.surfin.2021.101519}, abstract = {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.}, language = {en} } @misc{HezilAissaniFellahetal., author = {Hezil, Naouel and Aissani, Linda and Fellah, Mamoun and Samad, Mohammed Abdul and Obrosov, Aleksei and Chekalkin, Timofey and Marchenko, Ekaterina}, title = {Structural, and tribological properties of nanostructured α + β type titanium alloys for total hip}, series = {Journal of Materials Research and Technology}, journal = {Journal of Materials Research and Technology}, number = {19}, issn = {2238-7854}, doi = {10.1016/j.jmrt.2022.06.042}, pages = {3568 -- 3578}, abstract = {Titanium alloys are in demand for various biomedical applications and the most popular among them being, Ti-6Al-4V. Hence, in this study, Ti-6Al-7Nb are fabricated through the route of mechanical milling using different sintering temperatures. X-ray diffraction and hardness tests were conducted to characterize the developed sams to evaluate the effect of sintering temperatures on the structural and mechanical properties. It is observed that the sams sintered at a temperature of 1250 °C had the smallest crystallite and pore size, with enhanced relative density and mechanical properties. Tribological tests were conducted at varying normal loads to characterize the wear and frictional behaviour and showed that the sams sintered at 1250 °C presented the lowest friction coefficient and wear rate.}, language = {en} }