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Although TiAlN has been thoroughly studied, there is still an ongoing demand for developing new-based TiAlN films with enhanced protection efficiency for a long lifetime and high load-bearing capability linked to friction and corrosion mechanisms. This work aims to present the effect of Mo content by studying the structural tribo-mechanical, wettability, and corrosion behaviors in TiAlMoN coatings deposited by magnetron sputtering on cold-sprayed stainless steel 316L substrates. TiAlMoN coatings showed a dense columnar structure with the coexistence of titanium and molybdenum nitrides, and TiN (200) preferred orientation changed to TiN(111) with increasing Mo content. The surface energy of the TiAlMoN coatings decreased gradually with the increase in Mo content. The TiAlMoN coating containing 16.09 atom % Mo possesses the highest hardness and Young’s modulus (29.5 and 334.5 GPa, respectively) and the maximum H/E and H3/E2of 0.092 and 0.237, respectively. Formations of tribolayer oxides reduced the friction and enhanced the wear resistance of TiAlMoN coatings in atmospheric conditions and reached the minimum values of 0.3 and 0.849 × 10–6mm3/N, respectively, at 16.09 atom % of Mo under 5 N load charge. Corrosion examination in simulated seawater revealed that TiAlMoN coating-coated SS316L exhibited a significant positive shift of about −16 mV in corrosion potential with a notable reduction in corrosion current density (1.41 nA/cm2), confirming the improved corrosion performance. The combination of both cold spray and magnetron sputtering techniques for producing this kind of component is shown to have great potential in processing applications.

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.

TiN coatings with a thickness of 2 μm were deposited using the magnetron sputtering has developed rapidly over the last decade in such a way that it has become an established process of choice for the deposition of a wide range in various applications for different domains as it gives excellent performance in many aspects. In view of this, we have deposited the TiN coatings by magnetron sputtering using Ti target at different nitrogen content to study the influence of the nitrogen content on the mechanical properties and tribological behaviors of the TiN coatings were systematically investigated using nanoindentation and a pin-on-disk tribometer. Nanoindentation results shows that the hardness and Young's modulus of the TiN coatings increase with increasing N content in the coatings.Wear test results indicate that the wear rate and friction coefficient of the XC100 steel substrate were significantly reduced by deposition of the TiN coatings, and the tribological behaviors of the TiN coatings are strongly dependent on the nitrogen content in the coatings.

ABSTRACTCr–Zr–N films have been synthesised using R.F reactive magnetron sputtering system on Si (100) wafer and XC100 steel substrate without heating. The structural, mechanical and friction coefficient evolution as a function of the Zr content were investigated by XRD, (EDS, WDS), WPS, XPS, SEM, AFM, nanoindentation, Scratch adhesion and pin-on-disc sliding wear tests. The results show, that, with increasing Zr content, the film structure changed with the coexistence of (Cr–N, Zr–N) crystallographic orientation mixture. The films formed a (Cr, Zr) N solid solution where Zr atoms substitute Cr atoms. CrN lattice parameter increased from 4.17 to 4.32 Å with the crystallite size refinement. The mechanical parameters (H, σ, E, H/Eand H3/E2) were significantly improved in comparison to binary films, especially at 29 at.-% Zr. The friction and wear behaviour of the Cr–Zr (29 at.-% Zr)–N coating also showed a significant improvement.

Cr–Zr–N films have been synthesised using R.F reactive magnetron sputtering system on Si (100) wafer and XC100 steel substrate without heating. The structural, mechanical and friction coefficient evolution as a function of the Zr content were investigated by XRD, (EDS, WDS), WPS, XPS, SEM, AFM, nanoindentation, Scratch adhesion and pin-on-disc sliding wear tests. The results show, that, with increasing Zr content, the film structure changed with the coexistence of (Cr–N, Zr–N) crystallographic orientation mixture. The films formed a (Cr, Zr) N solid solution where Zr atoms substitute Cr atoms. CrN lattice parameter increased from 4.17 to 4.32 Å with the crystallite size refinement. The mechanical parameters (H, s, E, H/Eand H3/E2) were significantly improved in comparison to binary films, especially at 29 at.-% Zr. The friction and wear behaviour of the Cr–Zr (29 at.-% Zr)–N coating also showed a significant improvement.

The aim of the present research was focused on the study of the effect of replacing vanadium by niobium and iron on the tribological behavior of Hot Isostatic Pressed (HIPed) titanium alloy (Ti-6Al-4V) biomaterial, using a ball-on-disk type Oscillating tribometer, under wet conditions using physiological solution conditions (Ringer solution) in accordance with the ASTMG 99, ISO 7148-1:2012, and ASTM G 133–95 standards. The tests were carried out under a normal load of 6 N, with an AISI 52100 grade steel ball as a counter face. The morphological changes and structural evolution of the nanoparticle powders using different milling times (2, 6, 12 and 18 h) were studied. The morphological characterization indicated that the particle and crystallite size continuously decreases with increasing milling time to reach the lowest value of 4 nm at 18 hours milling. The friction coefficient and wear rate were lower in the samples milled at 18 h (0.226, 0.297 and 0.423) and (0.66 x10-2, 0.87x10-2 and 1.51x10-2 µm3.N-1.µm-1) for Ti-6Al-4Fe, Ti-6Al-4Nb and Ti-6Al-4V, respectively. This improvement in friction and wear resistance is attributed to the grain refinement at 18 hour milling. The Ti-6Al-4Fe samples showed good tribological performance for all milling times

From the hard and anti-corrosions coatings, we found the chromium carbides, these components were discovered by large studies; like thin films since years ago. They were pointed a good quality for the protection of steel, because of their thermal and mechanical properties for this reason, it was used in many fields for protection. Plus: their hardness and their important function in mechanical coatings. The aim of this work joins a study of the effect of the thermal treatment on mechanical and structural properties of the Cr/steel system. Thin films were deposited by cathodic magnetron sputtering on the steel substrates of 100C6, contain 1% wt of carbon. Samples were annealing in vacuum temperature interval between 700 to 1000 °C since 45 min, it forms the chromium carbides. Then pieces are characterising by X-ray diffraction, X-ray microanalysis and scanning electron microscopy. Mechanical properties are analysing by Vickers test. The X-ray diffraction analyse point the formation of the Cr7C3, Cr23C6 carbides at 900°C; they transformed to ternary carbides in a highest temperature, but the Cr3C2 doesn’t appear. The X-ray microanalysis shows the diffusion mechanism between the chromium film and the steel sample; from the variation of: Cr, Fe, C, O elements concentration with the change of annealing temperature. The variation of annealing temperature shows a clean improvement in mechanical and structural properties, like the adhesion and the micro-hardness.

CrVN coatings between 10 and 26 at.-% V were prepared by PVD to investigate the effect of V on the properties of CrN system. The films were analysed using, DRX, X microanalysis, AFM SEM, scratch, tribometer and nanoindentation testers.The DRX spectrum shows the formation of (CrN-VN) phases and the examinations morphology show that the progressive change in the structure mode with adding V. The study of mechanical behavior shows degradation in the hardness and elastic modulus. On the other hand, the Cr-V-N film has a good wear resistance which remains lower than that of CrN film. Detachment of the Cr-V-N layer is observed at the all scratch trace while the CrN film exhibits best adhesion performance.

This study aims to examine the effect of replacing vanadium by niobium and iron on the tribological behavior of hot-isostatic-pressed titanium alloy (Ti–6Al–4V) biomaterial, using a ball-on-disk-type oscillating tribometer, under wet conditions using physiological solution in accordance with the ISO7148 standards. The tests were carried out under a normal load of 6 N, with an AISI 52100 grade steel ball as a counter face. The morphological changes and structural evolution of the nanoparticle powders using different milling times (2, 6, 12 and 18 h) were studied. The morphological characterization indicated that the particle and crystallite size continuously decrease with increasing milling time to reach the lowest value of 4 nm at 18-h milling. The friction coefficient and wear rate were lower in the samples milled at 18 h (0.226, 0.297 and 0.423; and 0.66 × 10−2, 0.87 × 10−2and 1.51 × 10−2µm3N−1µm−1) for Ti–6Al–4Fe, Ti–6Al–7Nb and Ti–6Al–4V, respectively. This improvement in friction and wear resistance is attributed to the grain refinement at 18-h milling. The Ti–6Al–4Fe samples showed good tribological performance for all milling times.

This work aims at analyzing the scaling behavior and develop correlations during surface growing for different germination lengths. The surface growing by random deposition is simulated using a kinetic Monte Carlo approach, by considering different germination lengths. Different surface descriptors are extracted, among them the roughness and the correlation. The former allows extracting the scaling behavior, while the latter proves the existence of correlations independent of the system size but dependent on the germination length. Moreover, as in the case of random deposition with a null germination length, the growing roughness never saturates.