TY - CHAP A1 - Fellah, Mamoun A1 - Hezil, Naouel A1 - Abderrahim, Karima A1 - Samad, Mohammed Abdul A1 - Montagne, Alex A1 - Mejias, Alberto A1 - Iost, Alain A1 - Kossman, Stephania A1 - Chekalkin, Timofey A1 - Obrosov, Aleksei A1 - Weiß, Sabine T1 - Investigating the Effect of Sintering Temperature on Structural and Tribological Properties of a Nanostructured Ti–20Nb–13Zr Alloy for Biomedical Applications T2 - Characterization of Minerals, Metals, and Materials N2 - β-type Ti–20Nb–13Zr alloys with low Young’s modulus were prepared at different sintering temperatures (950, 1050, 1150, and 1250 °C). The morphological and structural characteristics of as-prepared samples were investigated by several methods. Wear tests were conducted using a ball-on-plate type oscillating tribometer under different applied loads (2, 10, and 20 N). The morphological characterization indicated that the mean pore and crystallite size continuously decreased with increasing sintering temperature to reach lowest values of 40 nm and 38 nm at 1250 °C, respectively. The relative density of the 1250 °C sintered sample was as high as 98.7%. Moreover, the higher sintering temperature resulted in higher relative density and closed porosity of the sample. Both the friction coefficient and wear rate were lower in the sample sintered at 1250 °C as compared to other samples. This enhancement in tribological properties was attributed to a closed porosity. KW - Ti-20Nb-13Zr KW - Nanobiomaterials KW - Tribological behaviour KW - Nanotribology KW - Sintering KW - Biomedical applications Y1 - 2020 SN - 978-3-030-36628-5 SN - 978-3-030-36627-8 U6 - https://doi.org/10.1007/978-3-030-36628-5_61 SN - 2367-1181 SN - 2367-1696 SP - 619 EP - 629 PB - Springer CY - Cham ER - TY - GEN A1 - Fellah, Mamoun A1 - Hezil, Naouel A1 - Touhami, Mohamed Zine A1 - Hussien, Mohammed A. A1 - Montagne, Alex A1 - Mejias, Alberto A1 - Iost, Alain A1 - Kossman, Stephania A1 - Chekalkin, Timofey A1 - Obrosov, Aleksei A1 - Weiß, Sabine T1 - Effect of Sintering Temperature on Mechanical and Tribological Behavior of Ti–Ni Alloy for Biomedical Applications T2 - TMS 2020 149th Annual Meeting & Exhibition Supplemental Proceedings N2 - Ti–Ni powder compacts were prepared by mechanical alloying (MA), followed by hot isostatic pressing (HIP). Afterwards, the samples were sintered at different temperatures (950, 1050, 1150 and 1250 °C). Microhardness, density, crystallite size as well as microstrain of the sintered samples were measured and analyzed. Wear characteristics in phosphate-buffered saline (PBS) solution was tested under different applied loads of 2 N, 10 N, and 20 N, respectively. The results indicated that the crystallite size continuously decreases with increasing sintering temperature and reaches the lowest value of 31.3 nm at 1250 °C. The relative density of the sample sintered at 1250 °C is 98.0%. Moreover, the higher sintering temperatures lead to the higher relative density and the increase in hardness and young’s modulus of the sample. At the same time the friction coefficient and wear rate were lower for the samples sintered at 1250 °C. This improvement in friction and wear resistance is attributed to the grain size refinement. Ti–Ni sintered at 1250 °C showed good tribological performance under all test conditions. KW - Ti–Ni KW - Nanobiomaterials KW - Tribological behaviour KW - Sintering KW - Biomedical applications Y1 - 2020 SN - 978-3-030-36295-9 SN - 978-3-030-36296-6 U6 - https://doi.org/10.1007/978-3-030-36296-6_157 SN - 2367-1181 SN - 2367-1696 SP - 1701 EP - 1710 PB - Springer CY - Cham ER - TY - GEN A1 - Hezil, Naouel A1 - Fellah, Mamoun A1 - Montagne, Alex A1 - Iost, Alain A1 - Obrosov, Aleksei A1 - Weiß, Sabine T1 - Removal of Chromium (VI) from Water onto Activated Carbon by Adsorption in Dynamic Mode T2 - TMS 2020 149th Annual Meeting & Exhibition Supplemental Proceedings N2 - Hexavalent chromium pollution from industrial waste water is a serious problem as it can cause adverse effects on the environment. Several methods are used to reduce the harmful effects of this pollutant, especially physico-chemical methods, such as adsorption technology. The present study aims to remove Cr (VI) from industrial sources in a fixed-bed column of activated carbon. The experiments were carried out at natural pH and temperature with a flow rate (5, 10, and 20 mL/min) and bed height (3.5 cm). Breakthrough curves for feed concentrations (0.01, 0.03, and 0.05 mol/L) were investigated. The results indicated a marked decrease up to 99%. The value of the flow constant for the Thomas model decreased with the increase in the concentration of the incoming substance, but increased with the increase in the flow rate. KW - Hexavalent chromium KW - Activated carbon KW - Adsorption KW - Breakthrough curve KW - Fixed-bed column Y1 - 2020 SN - 978-3-030-36295-9 SN - 978-3-030-36296-6 U6 - https://doi.org/https://doi.org/10.1007/978-3-030-36296-6_80 SN - 2367-1181 SN - 2367-1696 SP - 855 EP - 863 PB - Springer CY - Cham ER - TY - GEN A1 - Evdokimov, Anton A1 - Doynov, Nikolay A1 - Ossenbrink, Ralf A1 - Obrosov, Aleksei A1 - Weiß, Sabine A1 - Michailov, Vesselin T1 - Thermomechanical laser welding simulation of dissimilar steel-aluminum overlap joints T2 - International Journal of Mechanical Sciences N2 - Mixing of steel and aluminum within the weld pool during keyhole laser welding results in a complex dissimilar microstructure, which in turn, initiates a shift in weld metal mechanical properties. In this study, a numerical model for computation of distortions in laser-welded dissimilar overlap joints (austenitic stainless steel 304 – 6082-T6 aluminum alloy), which considers properties of the mixed steel-aluminum weld metal was developed. The required yield strength, Young's modulus, and strain hardening exponent of the weld metal were experimentally determined using the indentation technique coupled with energy-dispersive X-ray spectroscopy. The designed material model calculates the weld elastic-plastic properties as a function of the aluminum concentration. The softening of the alloys in the heat-affected zone was determined by physical simulations and considered as a function of maximum temperature. Computed and measured distortions showed good agreement for various welding regimes with an average deviation of 18.4%. The sensitivity analyses indicated that the application of the developed weld material model significantly improves the accuracy of the thermomechanical simulations. Y1 - 2021 U6 - https://doi.org/10.1016/j.ijmecsci.2020.106019 SN - 1879-2162 VL - 190 ER - TY - GEN A1 - Fellah, Mamoun A1 - Hezil, Naouel A1 - Touhami, Mohamed Zine A1 - Samad, Mohammed Abdul A1 - Obrosov, Aleksei A1 - Bokov, Dmitry O. A1 - Marchenko, Ekaterina A1 - Montagne, Alex A1 - Iost, Alain A1 - Alhussein, Akram T1 - Structural, tribological and antibacterial properties of (α + β) based ti-alloys for biomedical applications T2 - Journal of Materials Research and Technology N2 - Implant-related follow up complications resulting from poor implant integration, delamination, chipping, mechanical instability, inflammation or graft-vs-host reaction may lead to low patient tolerance, prolonged care and sometimes leading to a second surgery. Hence, there is an urgent need for developing biomaterials which will help to overcome the above compatibility problems. Ti based alloys have been widely used for biomedical applications, due to their excellent properties, such as low modulus, high biocompatibility and high corrosion resistance. In order to further improve the physical, mechanical and tribological properties of these alloys, microstructural modification is often required. Hence, this study aims to develop and evaluate the structural and tribological behavior of Hot Isostatic Pressed (HIPed) and sintered Ti-6Al-7Nb samples containing niobium, which is less toxic and less expensive as compared to the usual alloying element, vanadium (Ti-6Al-4 V). The Ti-6Al-7Nb alloys were fabricated by using nanoparticle powders milled for different durations (2, 6, 12 and 18 h) to evaluate the effect of milling time on the morphological and structural properties. Friction and wear tests were carried out on the (HIPed) and finally sintered Ti-6Al-7Nb alloy samples, to evaluate their tribological properties under different applied loads (2, 8 and 16 N), with an alumina α-Al2O3 ball as a counter face using an oscillating tribometer. The physical characterization of the nanopowders formed using different milling times indicated that the particle and crystallite size continually decreased with increasing milling time, while the microstrain increased. It is observed that the friction coefficient and wear rate for the samples prepared by powders milled for 18 h and tested under 2 N were lowest with values of 0.25 and 1.51 × 10−2 μm3∙N-1 μm-1, respectively compared to other milled samples. This improvement in tribological properties is attributed to the grain refinement at high milling times. The antibacterial evaluation of the fabricated alloys showed an improvement in antibacterial performance of the samples milled at 18 h compared to the other milling times. KW - Mechanical properties KW - Hot Isostatic Pressure KW - Ti-6Al-7Nb KW - Powder metallurgy KW - Milling time KW - Physical characterization KW - biomaterials KW - microstructure Y1 - 2020 UR - https://www.sciencedirect.com/science/article/pii/S2238785420318421 U6 - https://doi.org/10.1016/j.jmrt.2020.09.118 SN - 2238-7854 VL - 9 IS - 6 SP - 14061 EP - 14074 ER - TY - GEN A1 - Baigonakova, Gulsharat A1 - Marchenko, Ekaterina A1 - Chekalkin, Timofey A1 - Kang, Ji-hoon A1 - Weiß, Sabine A1 - Obrosov, Aleksei T1 - Influence of Silver Addition on Structure, Martensite Transformations and Mechanical Properties of TiNi–Ag Alloy Wires for Biomedical Application T2 - Materials N2 - The microstructural and functional behavior of TiNi-based wires with a silver content of 0–1.5 at.% was evaluated. The concentration range for Ag doping determined for the TiNi wires with potential for the medical industry was 0–0.2 at.%. Microstructure analysis of TiNi wires with different silver contents at room temperature indicated a multiphase structural state. Various internal structures with tangled grain boundaries were formed by intense plastic deformation. The nanocrystalline structure and phase state of wire with the minimum silver content (0.1 at.% Ag) provide full shape recovery, the greatest reversible strain, and optimal strength and ductility. TiNi ingots with a high Ag content (0.5–1.5 at.%) cracked under minimum load due to excess silver that crystallized along the grain boundaries and broke cohesion bonds between the TiNi grains. KW - shape memory alloy KW - silver KW - doping KW - mechanical properties KW - nanostructured material KW - wire Y1 - 2020 UR - https://www.mdpi.com/1996-1944/13/21/4721 U6 - https://doi.org/10.3390/ma13214721 SN - 1996-1944 VL - 13 IS - 21 ER - TY - GEN A1 - Saoudi, Adel A1 - Fellah, Mamoun A1 - Hezil, Naouel A1 - Lerari, Djahida A1 - Khamouli, Farida A1 - Atoui, L'hadi A1 - Bachari, Khaldoun A1 - Morozova, Iuliia A1 - Obrosov, Aleksei A1 - Samad, Mohammed Abdul T1 - Prediction of mechanical properties of welded steel X70 pipeline using neural network modelling T2 - International Journal of Pressure Vessels and Piping N2 - An artificial neural network (ANN) model was developed to predict tensile and impact properties of a submerged arc helical welded (SAHW) pipeline steel API X70 based upon its chemical composition. Weight percent of the elements was considered as the input, while the tensile and Charpy impact properties were considered as the outputs. Scatter diagrams and two statistical parameters (absolute fraction of variance and relative error) were used to evaluate the prediction performance of the developed artificial neural network model. The predicted values were found to be in excellent agreement with the experimental data and the current model has a good learning precision and generalization (for training, validation and testing data sets). The results revealed that the developed model is very accurate and has a strong potential for capturing the interaction between the mechanical properties and chemical composition of welded high strength low alloy (HSLA) steels. KW - API X70 KW - Artificial neural network (ANN) KW - Submerged arc welding KW - Modeling KW - Mechanical properties KW - Chemical composition Y1 - 2020 U6 - https://doi.org/10.1016/j.ijpvp.2020.104153 SN - 0308-0161 VL - 186 ER - TY - GEN A1 - Fellah, Mamoun A1 - Hezil, Naouel A1 - Guerfi, Kamel A1 - Djellabi, Ridha A1 - Montagne, Alex A1 - Iost, Alain A1 - Borodin, Kirill A1 - Obrosov, Aleksei T1 - Mechanistic pathways of cationic and anionic surfactants sorption by kaolinite in water T2 - Environmental Science and Pollution Research N2 - Surfactants are widely used in many chemical industries and as primary components of cleaning detergents due to their specific characteristics, which in turn results in high pollution of domestic and industrial wastewaters by such substances. In this study, the mechanistic pathways of the adsorption of cationic benzyl-dimethyl-dodecyl ammonium bromide (BDDAB) and anionic sodium dodecyl sulfate (SDS) surfactants on kaolinite clay in water were investigated. The results showed that the adsorption of anionic surfactant (SDS) on kaolinite is better compared with cationic surfactant (BDDAB), wherein the ♦maximum adsorption capacity was found 161.4 μmol g−1 and 234 μmol g−1 for BDDAB and SDS, respectively. Adsorption kinetics were the best suited to pseudo-second-order model for both BDDAB and SDS with an adsorption rate constant of 0.028 g μmol−1 min−1 and 0.023 g μmol−1 min−1, respectively. Meanwhile, the adsorption of BDDAB by kaolinite showed that the isotherm adsorption tended to follow the Langmuir-Freundlich and Freundlich isotherm models. However, the SDS adsorption isotherm obeyed only the Langmuir-Freundlich model. KW - Surfactant KW - Adsorption KW - Kaolinite KW - Water remediation KW - Adsorption modeling Y1 - 2021 UR - https://link.springer.com/article/10.1007/s11356-020-11083-6 U6 - https://doi.org/10.1007/s11356-020-11083-6 SN - 1614-7499 VL - 28 IS - 6 SP - 7307 EP - 7321 ER - TY - GEN A1 - Kokorev, Oleg A1 - Chekalkin, Timofey A1 - Marchenko, Ekaterina A1 - Yasenchuk, Yuri A1 - Gunther, Sergey A1 - Serebrov, Vladimir A1 - Chernyshova, Alena A1 - Obrosov, Aleksei A1 - Kang, Ji-hoon T1 - Exploring the role of surface modifications of TiNi-based alloys in evaluating in vitro cytocompatibility: a comparative study T2 - Surface Topography: Metrology and Properties N2 - The aim of this study was the comparative analysis of in vitro bio-testing of solid and porous TiNi samples with modified surfaces (intact, oxidated, and etched). Tests for cytocompatibility, hemolysis, and cytotoxicity (MTT) as well as visualization by confocal and scanning electron microscopy have shown that the chemically modified samples are the most cytocompatible. The intact and etched samples did not induce hemolysis greater than 2%, and thus they comply with the ISO 10993-4:2018 standard for hemolysis by blood-contacting biomaterials. Direct culture of etched samples with MCF-7 cells and human leukocytes showed low cytotoxicity. At the same time, the cytotoxicity of samples oxidated at 500 °C was significantly greater than that of the etched samples. Confocal and electron microscopy also confirmed the abovementioned quantitative data. The cells attached to the etched surface in numbers sufficient for them to be able to grow and proliferate on this substrate in vitro. These findings indicate that solid and porous TiNi alloy with surface modifications achieved by a cost-effective method is biotolerable and promising for clinical use and for tissue engineering. KW - biocompatibility KW - cytocompatibility KW - TiNi alloys KW - tissue engineering KW - surface modification Y1 - 2020 UR - https://iopscience.iop.org/article/10.1088/2051-672X/abc0f9/meta U6 - https://doi.org/10.1088/2051-672X/abc0f9 SN - 2051-672X VL - 8 IS - 4 ER - 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 -