Publications Internationales
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Item Physical, mechanical and thermal properties of Spanish broom (Spartium junceum L.) fibre reinforced unidirectional polyester composites(SAGE, 2025) Djerad, Abdelkader; Benhamadouche, Lamia; Moussaoui, Nafissa; Bennouioua, Tahar; Jawaid, MohammadThis research analyses Spanish broom fibres (Spartium junceum L.) as possible reinforcement in polymer composites. It includes fibre extraction, characterisation, and composite construction. We extracted the Spanish broom fibres by water retting for 30 days, followed by hand washing and air drying. The fibres were spun into skeins using circular spinning. The fibres exhibited a density of 1.27 ± 0.03 g/cm3 and an average diameter of 170 ± 1.80 μm. The SEM investigation revealed a rough, uneven surface with microfibrils and spaces, that are typical of lignocellulosic fibres. Cellulose, hemicellulose, and lignin were detected using FTIR analysis. TGA revealed three weight-reduction phases, with the most significant cellulose degradation temperature around 319°C. XRD analysis revealed a 48.09% crystallinity index and 15.7 nm crystallite size. Single fibre tensile testing showed an elastic modulus of 20.51 ± 5.30 GPa, a fracture stress of 486.17 ± 129.16 MPa, and a fracture strain of 1.57 ± 0.43%. Spanish broom yarn and polyester resin were used to create unidirectional composites. Results indicate that both unreinforced polyester and SJL fibre-reinforced composites have enhanced mechanical characteristics, with maximum stress of 29.79 ± 0.79 MPa and Young’s modulus of 3.10 ± 0.25 GPa. This work highlights the significance of employing Spanish broom fibres as a green reinforcing material for polymer composites and suggests future research optionsItem Durability Indices of a Sealing Mortar Incorporating Blast Furnace Slag(2025) Ikhaddalene, Soumia; Irekti, Amar; Oualit, MehenaGround granulated blast furnace slag generated from steel manufacturing presents environmental challenges, but it can be valuable when utilized as a supplementary material in concrete, contributing to the development of sustainable materials. In this research, a new sealing mortar was prepared by substituting 10% of the cement with slag (M10). This material can provide performance comparable to M234, a M0 sealer used for sealing and wedging supports and machine bases. The mechanical properties and durability indices of both M10 and M234 were compared to the reference mortar MISO, which is a laboratory-made mortar free of slag. XRD analysis was conducted to determine the crystallinity of the starting cement, and granulometry revealed a median size distribution of 23 μm for the slag after grinding. Capillary absorption and water-accessible porosity were tested for all samples.Item Relationship between structural and mechanical properties of polyethylene matrix nanocomposites(Faculty of Engineering, Khon Kaen University, 2024) Rahmaoui, Fath Eddine Zakaria; Belaidi, IdirThis study examined the impact of incorporating graphene nanoplatelets (GnP) into high-density polyethylene (PE) to create nanocomposites, with and without a compatibiliser. We specifically focused on the impact of structural crystallinity on the mechanical properties of the nanocomposites. These nanocomposites exhibited a much higher Young's modulus compared with pure PE. Specifically, the Young’s modulus increased exponentially with the addition of a compatibiliser and linearly without it. One explanation for this exponential rise in Young's modulus is that the crystal's compacted polymer chain structure improved its stiffness, facilitating effective load transfer. Additionally, a poor distribution of GnP in the nanocomposites with a filler content of 0.5 and 1 wt.%, both with and without a compatibiliser, led to a decreased stress and strain at break. However, at higher filler contents, well-distributed GnP play a key role in enhancing stress and strain at break.Item Exploring tensile properties of bio composites reinforced date palm fibers using experimental and Modelling Approaches(Elsevier, 2024) Saada, Khalissa; Zaoui, Moussa; Amroune, Salah; Benyettou, Riyadh; Hechaichi, Amina; Jawaid, Mohammad; Hashem, Mohamed Ibrahim; Uddin, ImranThe objective of this study was to assess the tensile strength of epoxy bio-composites reinforced with palm fibers, both untreated and treated with sodium carbonate NaHCO3 at a concentration of 10 % (w/v) for 24 and 96 h, with varying weight percentages of fibers (15 %, 20 %, 25 %, and 30 %). To predict the mechanical performance of the composites, two methods were employed: artificial neural network (ANN) and response surface methodology (RSM). A Box-Behnken RSM design was used to conduct experiments and establish a mathematical model of the bio-composite behavior as a function of the fiber percentage in the samples, specimen cross-section, and treatment time. The ANN forecasts showed consistent expected values for the bio-composite sample behavior, with a correlation coefficient (R2) greater than 0.98 for Young's modulus and 0.97 for stress. Similarly, the correlation coefficients obtained by RSM for the mechanical properties were also highly satisfactory, with an R2 of 0.89 for Young's modulus and 0.87 for stress. Finally, the errors generated by each method (Box-Behnken and ANN) were compared to the experimental results.Item A systematic DFT study of (Ti3/2RE1/2)AlC alloys: A new database for adjustable mechanical and electronic properties(Elsevier, 2022) Meftah, C.; Iles, N.; Rabahi, L.; Gallouze, M.; Feraoun, H.I.; Drir, M.In this study, ab initio calculations based on Pseudo-Potential Density Functional Theory (PP-DFT) method are carried out in order to highlight the partial substitution effect of Rare Earth (RE) elements in the well-known 211-MAX phase of Ti2AlC. The considered elements are Y, Sc and RE = La, Ce, Pr, Nd, Sm, Eu, Gd leading to (Ti3/2RE1/2)AlC alloys. According to the obtained results, the (Ti3/2RE1/2)AlC alloys are significantly less compressible under uniaxial stress along x and z axes. They exhibit high resistance to shearing along [removed] direction. In addition, the calculated heat capacity for (Ti3/2RE1/2)AlC alloys increases with respect to the temperature, a maximum is found in the temperature range 200–300 K. Localized states occur in (Ti3/2RE1/2)AlC alloys due to the f states filling of the rare earth elements. The magnetic moment of (Ti3/2RE1/2)AlC compounds increases according to 4fn(n=2 for Ce to n=7 for Gd) filling. Our findings provide a theoretical database for new tunable properties of (Ti3/2RE1/2)AlC alloysItem Wear Behavior and Microstructure of Thermally Sprayed NiCrBSiFeC and Composite NiCrBSiFeC-WC(Co) Coatings(2021) Abderrahmane, Abderrahmane; Gaceb, Mohamed; Cheikh, Mohammed; Le roux, SabineIn this work, a study was carried out on the friction and wear behavior of flame thermal sprayed NiCrBSiFeC-WC(Co) composite and NiCrBSiFeC coatings subjected to severe wear conditions. For this purpose, flame remelted samples were tested in reciprocating wear conditions based on a cylinder-on-flat configuration. The wear assessment of the coatings was achieved using scanning electron microscopy (SEM) and 3D optical profilometry. The microstructure and the mechanical properties of the coatings were investigated using SEM, EDS and XRD techniques as along with indentation tests. The tribological behavior of the substrate and the coatings was successfully studied thanks to wear tests conducted on an adapted multi test apparatus. The results show that both NiCrBSiFeC and composite coatings induced a significant increase in the steel substrate hardness and wear resistance due to the formation of precipitates with high hardness well dispersed within an ultra-crystalline structure. Besides, adding WC(Co) to NiCrBSiFeC leads to a composite coating with hardness and wear resistance further improved. In return, it increases the coefficient of friction (COF) and the coatings’ roughness. Furthermore, improvements in the surface hardness, the roughness and the coating-substrate adhesion were attained after the remelting process for both NiCrBSiFeC and NiCrBSiFeC-WC(Co) coatings. Wear tracks investigations indicated that reciprocating dry sliding based on cylinder-on-flat test configuration promote several wear mechanisms that may occur simultaneously.Item Dynamic characterization of the magnetomechanical properties of off axis anisotropic magnetorheological elastomer(De Gruyter Open, 2022) Bendjeddou, Walid; Aguib, Salah; Chikh, Noureddine; Nour, Abdelkader; Djedid, Toufik; Kobzili, Lallia; Meloussi, MounirThe use of magnetorheological elastomers in the mechanical and acoustic fields, by the automotive, aeronautical, and building industries, is currently developing strongly and rapidly. The perfect understanding of the capacity of smart insulation based on the absorption of the vibratory waves by magnetorheological elastomers materials passes by the knowledge of their dynamic mechanical behavior. In this present work, we have characterized the dynamic mechanical properties of the magnetorheological elastomer off axes anisotropy by the inclination, of different angles (15°, 30°, and 45°), of the pseudo-fibers of the iron particles formed by the application of a magnetic field at different intensities using an optimal loading rate of 30%. The rubber specimens were prepared by mixing micron-sized iron particles dispersed in room temperature vulcanized (RTV) silicone rubber by solution mixing. The experimental results obtained show a clear dependence of the effect of inclusion of ferromagnetic chains on the magnetomechanical properties. It is observed that the mechanical properties are better when applying a magnetic field of 0.6 T with an angle of inclination of 45°. The improvements added in this work could be useful in several industrial applications, such as automotive, aeronautic through adaptive control of damping and vibration levelItem Dissimilar FSW of AA2024 and AA7075 : effect of materials positioning and tool deviation value on microstructure, global and local mechanical behavior(Springer, 2021) Hadji, Idir; Badji, Riad; Gaceb, Mohamed; Cheniti, BillelIn this work, the effect of material location and tool deviation on global and local mechanical behavior of dissimilar AA2024/ AA7075 friction stir weld joints was investigated. The results showed that increasing the tool deviation value up to 1 mm towards the soft material, fixed in the advancing side, improved the material mixing quality and enhanced the grain refine- ment in the stir zone. It was found that the highest ultimate tensile strength was obtained when the AA7075 alloy was fixed in the retreating side for 1-mm tool deviation towards the AA2024 alloy. Above this deviation value, a gradual decrease of the global mechanical properties of the weld joints was noticed. The digital image correlation (DIC) technique coupled to tensile testing revealed an improvement of local strain in the stir zone as well as the heat-affected zones of the dissimilar joints when the AA2024 alloy was positioned in the advancing sideItem New generation of fiber self-compacting concrete based on pyrophyllite(ICE Publishing, 2021) Mansour, Sabria MalikaThe aim of this work is to develop new-generation ultra-high-performance fiber self-compacting concretes (SCCs) by introducing pyrophyllite rock powder as a cement substitute and assess its effects on the fresh and hardened properties. Three series of concretes were developed. The first series of reference fiber SCCs without pyrophyllite contained 1% adherent steel fibers or 1% slippery polymeric polypropylene fibers or a mixture of 0.5% steel and 0.5% polypropylene fibers. The second and the third series contained fibers and 10 or 20% pyrophyllite. The results showed that incorporation of pyrophyllite generates good fluidity, satisfactory stability without any risk of segregation and an ability to flow in a confined environment without risk of blocking of the fiber SCC. Moreover, the ultrasonic velocity, elastic dynamic modulus and rebound hammer number increase with increasing pyrophyllite rate. Also, a gain in compressive and flexural strengths was obtained at 28 days and the fiber SCCs were judged to be of good quality. The best formulation is the one containing steel fibers and 10% pyrophyllite. This additive has shown its potential to be used as a substitute for cement and its beneficial effect in protecting the environmentItem The effect of carbon black on the curing and mechanical properties of natural rubber/ acrylonitrile- butadiene rubber composites(Universidad Nacional Autonoma de Mexico, 2021) Boukfessa, Hind; Bezzazi, B.The present work investigates the effect of the amount of carbon black on curing and mechanical properties such as tensile strength, elongation at break, hardness and abrasion resistance of the natural rubber (NR)/ acrylonitrile-butadiene rubber (NBR) blend. For that purpose, a blend composed of 65% NR and 35% NBR filled with different content of carbon black N330 was used. The curing results indicate that the viscosity and the crosslink density of rubber composites increase and the scorch and curing times decrease with increasing the filler content. Mechanical properties such as tensile modulus and hardness of the CB filled NR/NBR blend were remarkably improved, indicating the inherent reinforcing potential of CB. Regarding tensile strength and abrasion resistance, they increase with the addition of carbon black, up to 50 phr. After that, these properties decrease slightly with filler addition
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