MOHAMED Benhamida

BENHAMIDA Riadh

Etude des propriétés électroniques et magnétiques de Mn2RuGa

SAGHIEUR Messaoud

Propriétés optiques des oxo-borate des terres rares

The structural, elastic and electronic properties of the ternary transition metal nitrides alloys TaxHf1-xN at (0-x-1) in the rock-salt structure are investigated by ab initio calculations. The calculations were performed using the first-principles Exact Muffin-Tin Orbitals method using full charge density technique within the framework of density functional theory. The compositional disorder is treated within the coherent potential approximation. The estimated formation enthalpy indicates that Ta0.5Hf0.5N is thermodynamically the most stable alloy. The obtained lattice parameters of the TaxHf1-xN alloys are in good agreement with other available theoretical and experimental values. The predicted elastic stiffness constants C11, C12 and indicate that the TaxHf1-xN alloys are mechanically stable and the addition of Ta increases their ductility. The Ta0.7Hf0.3N found to be hardest alloy. The correlation between Pettifor’s criterion (C12-C44) normalized by bulk modulus B and Pugh’s ratio G/B with increasing the degree of alloying x allowed us to predict that the critical value G/B=0.53, which correspond to x around 0.6 +/- 0.05, marks the brittle to ductile transition.

Citation

MOHAMED Benhamida , riadh guendouz , , (2025-02-01), Effects of Ta on the Structural, mechanical and electronic properties of the ternary alloys TaxHf1− xN: A computational study, Physica B: Condensed Matter, Vol:968, Issue:1, pages:416749, North-Holland

Bidirectional hybrid polymer-based composites are being introduced in many industrial applications. This is because the weaving patterns of woven composites have significant contributions to resulting composite performances. The main goal of this work was to study the effect of chemical treatments and the effect of hybridization on the mechanical properties of intra-layer hybrid Alfa/Jute fabric composites. Jute and Alfa fibers were used as natural fibers reinforcing the polyester matrix-based composites. First of all, the untreated, alkali and permanganate treated Alfa fibers were analyzed by using physical and mechanical tests (ATR-FTIR, XRD, and MEB). Weibull statistical analysis was employed to estimate the variability of untreated and treated Alfa fiber-resin interfacial shear strength. On the other hand, three plain-woven intra-ply hybrid fabrics were used as reinforcements for the polyester matrix. These three produced composite samples were subjected to mechanical, and physical tests such as three-point flexural strength, compressive strength, water absorption, and optical observation. The results were examined, analyzed, and compared to a jute-woven composite reinforced with the same resin. The results show that the chemical treatment can affect positively the fibers’ properties. In others hand, among the studied composites, the developed treated intra-ply woven fabric reinforced polyester resin have good mechanical properties in term of flexural and compression resistance. Weibull statistical analysis was conducted to evaluate and quantify the variability in the tensile strength of various intra-layer hybrid Alfa/Jute fabric composites

Citation

MOHAMED Benhamida , MANSOUR Rokbi , , (2025-01-21), Effect of chemical treatment on the mechanical properties of intra-layer hybrid Alfa/Jute fabric composites, Journal of Composite Materials, Vol:0, Issue:0, pages:27, SAGE Publications

STRUCTURAL AND ELASTIC PROPERTIES OF HIGH ENTROPY CARBIDE (TiMoHfNbTa)C: A FIRST-PRINCIPLES STUDY

Citation

MOHAMED Benhamida , riadh guendouz , ,(2024-11-20), STRUCTURAL AND ELASTIC PROPERTIES OF HIGH ENTROPY CARBIDE (TiMoHfNbTa)C: A FIRST-PRINCIPLES STUDY,International Conference on Material and Mechanic ICMM'2024,Boumerdes

Investigation of structural and elastic properties of high entropy

Citation

MOHAMED Benhamida , riadh guendouz , ,(2024-10-30), Investigation of structural and elastic properties of high entropy,The first International conference on technological application of materials,Setif

Ductility behaviour of a ternary transition metal nitride alloys: a first-principles study

Citation

MOHAMED Benhamida , riadh guendouz , ,(2024-10-26), Ductility behaviour of a ternary transition metal nitride alloys: a first-principles study,International Seminar on Materials and Engineering Structures (ISMES’2024),RELIZANE

This study presents the measured data of the "Oued Keberit" PV plant over a period of four months (January to April 2022) after nearly 6 years of outdoor exposure to the climate of Souk Ahras, eastern Algeria, in order to evaluate the performance of the solar PV system. This evaluation includes the calculation of PV system performance variables such as module performance, final performance and performance of the module references, system losses, photovoltaic friendly efficiency, system efficiency, performance ratio and capacity factor based on measured data, allowing comparison of actual PV system performance and reference values determined by manifacturers. The results showed that the four-month average values of the parameters Eac, Yr, Yf, PR, h, CF are 1.06375125MWh, 4.08h, 4.25h, 1.06, 16.40%, 60.28% respectively. Also, the high efficiency of the photovoltaic system was obtained during winter, due to the low temperature and the sufficient amount of solar radiation. However, the photovoltaic system generates a lot of energy during summer, although there is less output than during the winter season. This is because summer has maximum values for sunshine duration and solar radiation.

Citation

MOHAMED Benhamida , rzohir.torki@univ-msila.dz, , (2023-12-15), Effects of Temperature and Solar Radiation on Photovoltaic Modules Performances Installed in Oued Keberit Power Plant, Algeria, Journal of Advanced Research in Fluid Mechanics and Thermal Sciences, Vol:112, Issue:1, pages:204-216, Scopus

Bio-based composites are outstanding materials to replace many synthetic fiber-based composites due to their biodegradability and sustainable environmental properties. This research aims to characterize and analysis a new cellulosic fibers extracted from Echinops spinosissimus plant stem, to study their integration in the field of various industries such as composites and textiles. Thus, adding and incorporating a new natural fiber to the list of fibers that enter into the production of Bio-based composites materials, and meet the needs of the market that knows a shortage of these materials. In addition, the extracted fibers from Echinops spinosissimus plant, which is abundant and have acceptable properties that can replace the synthetic fibers. The stem anatomy results showed a strong presence of fiber cells, fiber SEM micrographs showed that fiber surface become rough, these fibers have a density of 0.97 ± 0.01 g/cm3, and diameter 280.76 µm. FTIR and XRD showed that these fibers are cellulosic. Thermal analysis revealed that Echinops spinosissimus fiber have a thermal stability of 208°C. Tensile strength, Young modulus and strain at failure were found as 217.54 ± 54.16 MPa, 19.23 ± 0.76 GPa and 3.78 ± 0.36%, respectively. SEM showed that the studied fiber becomes more roughness in the outer surface following the chemical treatments, thus contributing to better adhesion with resin. This work confirmed that Echinops spinosissimus fibers are suitable materials for use in textile and biocomposite applications.

Citation

MOHAMED Benhamida , sidali ZERNADJI , , (2023-10-25), Extraction and characterization of novel natural cellulosic fiber from Echinops spinosissimus plant stem, Journal of Composite Materials, Vol:57, Issue:29, pages:4503-4519, SAGE Publications

In the last few years, several techniques for separate determination of adhesion and friction in micromechanical tests have been developed but their experimental realization is rather complicated, because they require an accurate value of the external load at the moment of the crack initiation. So, in this perspective, an effort is done to estimate the interfacial parameters between two kind of thermoset resins and the natural Alfa fiber determined from Microbond tests. As known, the diameter of natural fiber is a crucial factor that participates in the estimation of the interfacial adhesion characteristics. In others words, the measurement of the maximum force required to pull out a fiber from the polymeric resins is investigated by using the micro-droplet test.

Citation

sidali ZERNADJI , MANSOUR Rokbi , MOHAMED Benhamida , , (2022-01-08), Estimation of fiber/polymer bond strength from maximum load values recorded in the micro-bond tests, Materials Today: Proceedings, Vol:53, Issue:2022, pages:247–252, Science Direct, Elsevier

In the last few years, several techniques for separate determination of adhesion and friction in micromechanical tests have been developed but their experimental realization is rather complicated, because they require an accurate value of the external load at the moment of the crack initiation. So, in this perspective, an effort is done to estimate the interfacial parameters between two kind of thermoset resins and the natural Alfa fiber determined from Microbond tests. As known, the diameter of natural fiber is a crucial factor that participates in the estimation of the interfacial adhesion characteristics. In others words, the measurement of the maximum force required to pull out a fiber from the polymeric resins is investigated by using the micro-droplet test.

Citation

MOHAMED Benhamida , MANSOUR Rokbi , , (2022), Estimation of fiber/polymer bond strength from maximum load values recorded in the micro-bond tests, Materials Today: Proceedings, Vol:53, Issue:1, pages:247-252, Materials Today

Based on ab-initio calculations, we have investigated the structural, electronic, and magnetic properties of diluted magnetic semiconductors with (K, Mn) substitution in the parent compounds, BaFZnAs and BaFMnAs. The coexistence of two types of magnetic exchange coupling interactions was detected via the calculation of the distance-resolved and the individual exchange parameters , where runs over the th nearest neighbor atom () of the reference one distanced by . The short-range interactions (SRI), at and , are strongly influenced by hole doping and substitutional disorder of both hole and spin co-doping. The long-range interaction (LRI), at distances beyond the , of a ferromagnetic nature, is less sensitive to hole doping, although these holes are the reason for their appearance. The results analysis showed that the dependence of the LRI on doping ratio, in the co-doping system, is more systematic than on the or doping separately. In (BaK)F(ZnMn)As system, a peak appears in the LRI at around 1.5 of doping ratio. Therefore, an estimation of the optimal hole doping for each spin doping concentration was given, where it is important to obtain the maximal ferromagnetic coupling, therefore the highest ferromagnetic ordering temperature, . Our findings are consistent with experiments, manifested, especially, in the saturation of the ordering temperature at large hole doping, as was obtained for the experimental of system. The results also show a doubling of the when the spin doping is doubled at high hole doping. Finally, we demonstrated via a proposed model that the SRI has the Ruderman–Kittel–Kasuya–Yosida (RKKY) interaction nature.

Citation

MOHAMED Benhamida , , (2022), Competing long-range and short-range interactions in ferromagnetic semiconductors: Evidence from first principle calculations, Journal of Magnetism and Magnetic Materials, Vol:559, Issue:1, pages:169518, Elsevier

composites materials have been widely used in engineering fields like civil, automotive, and aerospace industry, due to their high light weight, strength, and longue life expectancy. In the present study, biocomposites were prepared from thermoset resins named unsatured Polyester (UP) as matrix, and sisal ( Agave fourcroydes) as natural reinforcing fibers, requires a strong adhesion between fiber and matrix., biocomposites were prepared by putting small drops of synthetic matrix (UP) on the untreated and 3% NaOH alkali treated sisal fibers. The mechanical properties of the sisal fibers were studied by tensile strength tests, where mechanical properties of biocomposites prepared were characterized in terms of microbond tests, by estimating the values of external loads at moment of crack initiation. The results of mechanical properties showed a significant improvement for tensile strength and young's modulus was observed for treated sisal fiber, also a good interfacial adhesion with treated sisal fibers and matrix.

Citation

sidali ZERNADJI , MANSOUR Rokbi , MOHAMED Benhamida , ,(2022), STUDY OF THE INTERFACIAL ADHESION BETWEEN SISAL FIBERS AND THE POLYMER MATRIX BY MICRO-BOND TESTS,IMMAT' 2022,Sousse, Tunisie

The mechanical properties of transition metal carbides Ti x M1–x C (0 ≤ x ≤ 1) alloys, with TM = Nb, V and Zr, were carried out using a first-principles pseudopotential calculation. The Ti substitution by a transition metal TM is assumed to completely random so we can use the virtual crystal approximation (VCA) for the disordered alloys. These calculation shows that the mechanical properties are largely affected by the alloying due to the interplay between ionic and covalent bonding of TM-C. The TiNbC and TiVC show an increase of the hardness with increasing x, while for TiZrC a decrease is observed. The variation of elastic constants is correlated to the electronic structure and the nature of bonding for TMC.

Citation

MOHAMED Benhamida , Nadjib Baadji , Kh. Bouamama, , (2019), Computational Study of Mechanical and Electronic Properties of Transition Metal Carbides Ti x M1–x C with M = Nb, V and Zr, Journal of Nanoelectronics and Optoelectronics, Vol:14, Issue:4, pages:622, American Scientific Publishers

First-principles pseudopotential calculations of the lattice constants and of the single-crystal elastic constants for TixTa1 − xN (0 ≤ x ≤ 1) alloys with B1-rocksalt structure were first carried out. These calculations were performed using density functional perturbation theory (DFPT) within the virtual crystal approximation (VCA) for the disordered alloys and the supercell method (SC) for the ordered alloys, with the ABINIT program. For disordered structures, partial comparisons of the lattice constants and of the bulk modulus are provided with calculations that used the coherent potential approximation (CPA) with the exact muffin-tin orbitals (EMTO). For the exchange-correlation potential we used the generalized gradient methods (GGA). The calculated equilibrium lattice parameters by VCA are in good agreement with the stress-free lattice parameters a0 and exhibit a positive deviation from Vegard's rule corresponding to a positive bowing parameter while the calculated single-crystal stiffness c12 and c44, gradually increase when c11 decreases from TaN to TiN. In a second stage, we have estimated by homogenization methods the averaged stiffnesses , the Young modulus and Poisson ratio of polycrystalline TixTa1 − xN (0 ≤ x ≤ 1) alloys considering a random orientation of crystallites. Finally, comparisons are made with the experimental effective out-of-plane shear elastic modulus C44 and the effective out-of-plane longitudinal elastic constant C33 measured by Brillouin light scattering and picosecond ultrasonics, respectively, on thin films elaborated by magnetron sputtering.

Citation

MOHAMED Benhamida , P. Djemiaa, Kh. Bouamama, L. Belliard, D. Faurie, G. Abadias, , (2013), Structural and elastic properties of ternary metal nitrides TixTa1 − xN alloys: First-principles calculations versus experiments, Surface and Coatings Technology, Vol:215, Issue:1, pages:199, Elsevier

In this paper, the dependence of the optical properties of thin titanium nitride films deposited by reactive DC magnetron sputtering on different nitrogen pressures, as well as the electrical properties and mechanical properties is investigated. The normal reflectivity is measured in a range from 0.5 to 5.5 eV. The results have been fitted using a dielectric function which takes into account the presence of several Lorentz oscillators. Contributions to the absorption due to bound and conduction electrons are separated. This approach allows the computation of the mean free path of conduction electrons, screened plasma energy, and the optical conductivity, which informed about the nature of the defects in TiNx compound.

Citation

MOHAMED Benhamida , A. Meddour, S. Zerkout, S. Achour, , (2006), Calculation of the optical and electronic properties of TiNx thin films on domain IR–VIS–UV, Journal of Molecular Structure, Vol:777, Issue:1, pages:41, Elsevier