TY - GEN A1 - Yasenchuk, Yuri A1 - Marchenko, Ekaterina A1 - Baigonakova, Gulsharat A1 - Gunther, Sergey A1 - Kokorev, Oleg A1 - Gunther, Victor A1 - Chekalkin, Timofey A1 - Topolnitskiy, Evgeniy A1 - Obrosov, Aleksei A1 - Kang, Ji-hoon T1 - Study on tensile, bending, fatigue, and in-vivo behavior of porous SHS-TiNi alloy used as a bone substitute T2 - Biomedical Materials N2 - Intermetallic porous SHS–TiNi alloys exhibit tangled and specific stress-strain characteristics. The article aims to evaluate the findings emanated from experiments using standard and proprietary instruments. Fatigue testing under repeated complex loading was used to measure the total number of load cycles to failure of SHS-TiNi samples. 70% of the tested samples, passed through 106 cycles without failure due to the reversible martensite transformation in the TiNi phase, one of the prevailing constituents of a multiphase matrix. The fractured surfaces were analyzed using SEM and confocal laser scanning instruments. Microscopic studies showed that the entire surface of the sample is concealed with the miscellaneous strata resulted from the SHS process, which effectively protect the porous alloy in a corrosive environment. Numerous non-metallic inclusions, which are also attributed to the SHS reaction, do not have a significant impact on the deformation behavior and fatigue performance. In this context, the successful in vivo functioning of porous grafts assessed in a canine rib-plasty model allows the bone substitute to be congruentially deformed in the body without rejection and degradation, having a long operational life, often greater than 17 million cycles. It acknowledges the potential benefits of SHS–TiNi as a superior osteoplastic material and its high resistance to corrosion fatigue. KW - porous TiNi KW - self-propagating high-temperature synthesis KW - fatigue strength KW - corrosion fatigue KW - biocompatibility Y1 - 2021 UR - https://iopscience.iop.org/article/10.1088/1748-605X/aba327/meta U6 - https://doi.org/10.1088/1748-605X/aba327 SN - 1748-605X VL - 16 IS - 2 ER - TY - GEN A1 - Hazil, Naouel A1 - Fellah, Mamoun A1 - Montagne, Alex A1 - Iost, Alain A1 - Obrosov, Aleksei A1 - Weiß, Sabine T1 - Study of the photocatalytic degradation of Orange methyl dye in the presence of titanium dioxide T2 - La Troisième Conférence Méditerranéenne de la Biodiversité 2019 (BIODIV 2019) N2 - The use of photocatalytic techniques for water purification and wastewater treatment is very widespread, in our work we used TiO2 to photocatalyrate orange methyl (MO). In addition, the effects of some parameters on photodegradation of MO have been studied, such as the presence and / or absence of light (UV). The use of TiO2 showed a high MO degradation efficiency of up to 98%. The presence of H2O2 in the photocatalytic reaction may favor the photocatalytic degradation efficiencies. In addition, the experimental results have demonstrated an excellent rate of the order of 99%. KW - Titanium Dioxide KW - Photocatalytic Degradation Y1 - 2019 UR - http://ascob.net/files/abstract_book_biodiv2019_finale.pdf SP - 105 PB - L’ASCOB-SYRTIS CY - Hammamet, Tunisie ER - TY - GEN A1 - Morozova, Iuliia A1 - Obrosov, Aleksei A1 - Naumov, Anton A1 - Królicka, Aleksandra A1 - Golubev, Iurii A1 - Bokov, Dmitry O. A1 - Doynov, Nikolay A1 - Weiß, Sabine A1 - Michailov, Vesselin T1 - Impact of Impulses on Microstructural Evolution and Mechanical Performance of Al-Mg-Si Alloy Joined by Impulse Friction Stir Welding T2 - Materials N2 - Impulse Friction Stir Welding (IFSW) was utilized to join 6082–T6 alloy plates at various impulse frequencies. A distinctive feature of IFSW is the generation of mechanical impulses that enhances the forging action of the tool, and thereby, alters the weld microstructure. The microstructural evolution in the Stir Zone (SZ) with special focus on the strengthening precipitation behavior, and overall mechanical properties of the IFSW joints have been investigated. It was demonstrated that the strengthening β″ precipitates reprecipitated in the SZ of the IFSW joints during natural aging. In contrast, no precipitates were found in the SZ of the Friction Stir Welding (FSW) weld. Partial reversion of β″ after IFSW is supposed to occur due to more developed subgrain network and higher dislocation density introduced by impulses that accelerated precipitation kinetics. Dynamic recrystallisation was facilitated by impulses resulting in a fine, homogeneous structure. There was no significant difference between the microhardness in the SZ, tensile and yield strength of the FSW and IFSW joints. However, the application of impulses demonstrated the smoothing of the hardness reduction in the transition region at the advancing side. The shift of the fracture location from the Heat-Affected Zone (HAZ) by FSW to the SZ as well as higher elongation of the joints by IFSW of lower frequencies could be related to the grain refinement and the change of the grain orientation. KW - Al-Mg-Si alloy KW - impulse friction stir welding (IFSW) KW - precipitation KW - microstructure evolution KW - mechanical properties Y1 - 2021 UR - https://www.mdpi.com/1996-1944/14/2/347/htm U6 - https://doi.org/https://doi.org/10.3390/ma14020347 SN - 1996-1944 VL - 14 IS - 2 ER - TY - GEN A1 - Biedunkiewicz, Anna A1 - Figiel, Paweł A1 - Garbiec, Dariusz A1 - Obrosov, Aleksei A1 - Pawlyta, Mirosława A1 - Biedunkiewicz, Witold A1 - Pruss, Przemysław A1 - Rokosz, Krzysztof A1 - Wróbel, Rafał A1 - Raaen, Steinar A1 - Weiß, Sabine A1 - Bokov, Dmitry O. T1 - Influence of Elemental Carbon (EC) Coating Covering nc-(Ti,Mo)C Particles on the Microstructure and Properties of Titanium Matrix Composites Prepared by Reactive Spark Plasma Sintering T2 - Materials N2 - This paper describes the microstructure and properties of titanium-based composites obtained as a result of a reactive spark plasma sintering of a mixture of titanium and nanostructured (Ti,Mo)C-type carbide in a carbon shell. Composites with different ceramic addition mass percentage (10 and 20 wt %) were produced. Effect of content of elemental carbon covering nc-(Ti,Mo)C reinforcing phase particles on the microstructure, mechanical, tribological, and corrosion properties of the titanium-based composites was investigated. The microstructural evolution, mechanical properties, and tribological behavior of the Ti + (Ti,Mo)C/C composites were evaluated using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), electron backscatter diffraction analysis (EBSD), X-ray photoelectron spectroscopy (XPS), 3D confocal laser scanning microscopy, nanoindentation, and ball-on-disk wear test. Moreover, corrosion resistance in a 3.5 wt % NaCl solution at RT were also investigated. It was found that the carbon content affected the tested properties. With the increase of carbon content from ca. 3 to 40 wt % in the (Ti,Mo)C/C reinforcing phase, an increase in the Young’s modulus, hardness, and fracture toughness of spark plasma sintered composites was observed. The results of abrasive and corrosive resistance tests were presented and compared with experimental data obtained for cp-Ti and Ti-6Al-4V alloy without the reinforcing phase. Moreover, it was found that an increase in the percentage of carbon increased the resistance to abrasive wear and to electrochemical corrosion of composites, measured by the relatively lower values of the friction coefficient and volume of wear and higher values of resistance polarization. This resistance results from the fact that a stable of TiO2 layer doped with MoO3 is formed on the surface of the composites. The results of experimental studies on the composites were compared with those obtained for cp-Ti and Ti-6Al-4V alloy without the reinforcing phase. KW - nanocomposites KW - TiMMCs KW - spark plasma sintering KW - (Ti,Mo)C/C KW - EBSD KW - fracture toughness Y1 - 2021 UR - https://www.mdpi.com/1996-1944/14/1/231 U6 - https://doi.org/https://doi.org/10.3390/ma14010231 SN - 1996-1944 VL - 14 IS - 1 ER - TY - GEN A1 - Marchenko, Ekaterina A1 - Baigonakova, Gulsharat A1 - Dubovikov, Kirill A1 - Yasenchuk, Yuri A1 - Chekalkin, Timofey A1 - Obrosov, Aleksei T1 - Comparative study on the high-temperature oxidation resistance of porous and solid TiNi-based alloys T2 - Surface Topography: Metrology and Properties N2 - The present work aims to characterize the surface features of solid and porous (sintered and SHS) TiNi-based alloys subjected to oxidation at 1000 °C in static air in the context of their resistance to high-temperature atmospheric attack. Clear differences between the intact and oxidated surfaces indicate the complexity of a chemicothermal diffusion process evolving therein. Microscopic and XRD studies showed that the dominant superficial constituent in all oxidated samples is titanium dioxide in the rutile modification. The phase and structural properties of the surface layers suggest that porous sintered and solid alloys are most susceptible to high-temperature corrosion due to bare reactive surfaces, which negatively affects their overall biocompatibility. Surface morphology analysis revealed microporous and loose superficial layers having a thickness of 8–10 and 50–60 μm, respectively in the solid and sintered alloy. Also, these alloys showed a high content of leaching NiO and free Ni within the surface layer. Conversely, a thin (0.5–0.6 μm), dense, and multifarious layer of oxycarbonitrides Ti4Ni2(O,N,C) concealing the porous SHS-TiNi matrix inhibits the negative effect of high-temperature oxidation. KW - high-temperature oxidation KW - TiNi alloys KW - rutile KW - oxycarbonitrides KW - diffusion Y1 - 2021 UR - https://iopscience.iop.org/article/10.1088/2051-672X/abf324/meta U6 - https://doi.org/https://doi.org/10.1088/2051-672X/abf324 SN - 2051-672X VL - 9 IS - 2 ER - TY - GEN A1 - Fouzia, Hammadi A1 - Fellah, Mamoun A1 - Hezil, Naouel A1 - Aissani, Linda A1 - Mimanne, Goussem A1 - Mechachti, Said A1 - Samad, Mohammed Abdul A1 - Montagne, Alex A1 - Iost, Alain A1 - Weiß, Sabine A1 - Obrosov, Aleksei T1 - The effect of milling time on the microstructure and mechanical properties of Ti-6Al-4Fe alloys T2 - Materials Today Communications N2 - 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. KW - Ti-based alloys KW - Microstructure KW - Mechanical properties KW - Ball-milling KW - Biomaterials KW - Milling time Y1 - 2021 UR - https://www.sciencedirect.com/science/article/abs/pii/S2352492821004207#! U6 - https://doi.org/10.1016/j.mtcomm.2021.102428 SN - 2352-4928 VL - 27 ER - TY - GEN A1 - Grudinin, V. A. A1 - Sidelev, D. V. A1 - Bleykher, G. A. A1 - Yuriev, Yu N. A1 - Krivobokov, V. P. A1 - Berlin, E. V. A1 - Grigoriev, V. Yu A1 - Obrosov, Aleksei A1 - Weiß, Sabine T1 - Hot target magnetron sputtering enhanced by RF-ICP source for CrNx coatings deposition T2 - Vacuum N2 - This article describes hot Cr target magnetron sputtering enhanced by a radio-frequency inductively coupled plasma (RF-ICP) source in an Ar + N2 atmosphere. Optical emission spectroscopy revealed an opportunity to perform magnetron sputtering in an inert (Ar) atmosphere, while the CrNx coating can be deposited on a substrate in a chemically reactive atmosphere formed by the RF-ICP source. High stability and repeatability of deposition process were observed, and the deposition rate of the CrNx coatings increased from 106 to 127 nm/min as N2 flow rate rose. The power of the RF-ICP source and the N2 flow rate can be used to tailor and control deposition conditions. The XRD and WDS measurements showed the effect of deposition conditions on the crystal structure and elemental composition of CrNx coatings. It was found that the change of substrate bias, RF-ICP source power and N2 flow rate result in variation of coating stoichiometry from pure Cr to CrN. KW - CrN coatings KW - Hot target KW - Magnetron sputtering KW - High-rate deposition KW - RF inductively Coupled plasma Y1 - 2021 UR - https://www.sciencedirect.com/science/article/pii/S0042207X21003523?via%3Dihub#! U6 - https://doi.org/10.1016/j.vacuum.2021.110400 SN - 0042-207X VL - 191 ER - TY - GEN A1 - Krzywiński, Kamil A1 - Sadowski, Łukasz A1 - Stefaniuk, Damian A1 - Obrosov, Aleksei A1 - Weiß, Sabine T1 - Engineering and Manufacturing Technology of Green Epoxy Resin Coatings Modified with Recycled Fine Aggregates T2 - International Journal of Precision Engineering and Manufacturing-Green Technology N2 - Nowadays, the recycled fine aggregate sourced from construction and demolition waste is not frequently used in manufacturing of epoxy resin coatings. Therefore, the main novelty of the article is to prepare green epoxy resin coatings modified with recycled fine aggregate in a replacement ratio of natural fine aggregate ranged from 20 to 100%. The microstructural properties of the aggregates and epoxy resin were analyzed using micro-computed tomography, scanning electron microscopy and nanoindentation. The macroscopic mechanical properties were examined using pull-off strength tests. The highest improvement of the mechanical properties was observed for epoxy resin coatings modified with 20% of natural fine aggregate and 80% of recycled fine aggregate. It has been found that even 100% of natural fine aggregate can be successfully replaced using the recycled fine aggregate with consequent improvement of the pull-off strength of analyzed epoxy resin coatings. In order to confirm the assumptions resulting from the conducted research, an original analytical and numerical failure model proved the superior behavior of modified coating was developed. KW - Manufacturing KW - Wear KW - Composite KW - Epoxy resin coating KW - Recycled aggregate KW - Green material Y1 - 2022 UR - https://link.springer.com/article/10.1007/s40684-021-00377-w U6 - https://doi.org/10.1007/s40684-021-00377-w SN - 2198-0810 VL - 9 IS - 1 SP - 253 EP - 271 ER - TY - GEN A1 - Aissani, Linda A1 - Fellah, Mamoun A1 - Chadli, Abdel Hakim A1 - Samad, Mohammed Abdul A1 - Cheriet, Abderrahmane A1 - Salhi, Faiza A1 - Nouveau, Corinne A1 - Weiß, Sabine A1 - Obrosov, Aleksei A1 - Alhussein, Akram T1 - Investigating the effect of nitrogen on the structural and tribo-mechanical behavior of vanadium nitride thin films deposited using R.F. magnetron sputtering T2 - Journal of Materials Science N2 - 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. Y1 - 2021 U6 - https://doi.org/10.1007/s10853-021-06393-0 SN - 1573-4803 SN - 0022-2461 VL - 56 IS - 30 SP - 17319 EP - 17336 ER - TY - GEN A1 - Aissani, Linda A1 - Fellah, Mamoun A1 - Belgroune, Ahlam A1 - Obrosov, Aleksei A1 - Samad, Mohammed Abdul A1 - Alhussein, Akram T1 - Effect of O2 flow rate on the structure, wettability and tribo-mechanical behaviour of Zr-O-N thin films T2 - Surfaces and Interfaces N2 - 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. KW - Magnetron sputtering KW - Zr-O-N KW - Microstructure KW - Wettability KW - Surface Energy KW - Nanoindentation KW - Friction Y1 - 2021 UR - https://www.sciencedirect.com/science/article/abs/pii/S2468023021005186#! U6 - https://doi.org/10.1016/j.surfin.2021.101441 SN - 2468-0230 VL - 26 ER -