Publications Internationales
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Item Elaboration et caractérisation mécanique d’un matériau composite hybride(2006) Hachemane, B.; Mir, A.; Bezzazi, B.Item Experimental study of sandwich multilayer reinforced by glass fibre and agglomerated cork(2014) Hami, Brahim; Irekti, Amar; Aribi, C.; Bezzazi, B.; Mir, A.This paper presents an experimental study which is determined the mechanical properties of a composite material sandwich multilayer developed in the laboratory of mechanics of materials and composites, Materials Research Unit, process and en¬vironment. This type of sandwich is composed of four layers laminated based on an epoxy resin reinforced by woven glass fibres and mast between which three plates of agglomerated cork with stacked alternately laminated layers. Specimens for bending tests three and four points were prepared from the multilayer sandwich panels. A first series of static three-point bending tests shows a clear difference in the fracture behaviour for materials, laminate and cork. These materials have undergone a large plastic deformation without rupture achieve full sandwich, with the onset of delamination between layers laminated material and cork. In order to determine the bending stiffness modules D, the shear modulus and flexural N and the shear modulus of the soul Ga, we conducted a second test campaign four points bending. As a result, we can develop a variety of white cork produced in Algeria in order to use it in the construction and automotive industriesItem Study of the green composite Jute/Epoxy(2014) Mir, A.; Aribi, C.; Bezzazi, B.Work presented is interested in the characterization of the quasistatic mechanical properties and in fatigue of a composite laminated in jute/epoxy. The natural fibers offer promising prospects thanks to their interesting specific properties, because of their low density, but also with their bio-deterioration. Several scientific studies highlighted the good mechanical resistance of the vegetable fiber composites reinforced, even after several recycling. Because of the environmental standards that become increasingly severe, one attends the emergence of eco-materials at the base of natural fibers such as flax, bamboo, hemp, sisal, jute. The fatigue tests on elementary vegetable fibers show an increase of about 60% of the rigidity of elementary fibers of hemp subjected to cyclic loadings. In this study, the test-tubes manufactured by the method infusion have sequences of stacking of 0/90° and ± 45° for the shearing and tensile tests. The quasistatic tests reveal a variability of the mechanical properties of about 8%. The tensile fatigue tests were carried out for levels of constraints equivalent to half of the ultimate values of the composite. Once the fatigue tests carried out for well-defined values of cycles, a series of static tests of traction type highlights the influence of the number of cycles on the quasi-static mechanical behavior of the laminate jute/epoxyItem Study of mechanical and thermomechanical properties of jute/epoxy composite laminate(2010) Mir, A.; Zitoune, R.; Collombet, F.; Bezzazi, B.This article presents the development and the characterization of composite material (laminate) containing natural jute fiber reinforcement. Thermal characterization of jute fiber reinforcement shows the influence of the temperature on the mechanical behavior of fiber. At 180 C the jute fabric loses 50% of its mechanical characteristics. The laminate obtained by a process known as infusion is polymerized at a temperature lower than that which affects the mechanical properties of dry fabric. The digital image correlation carried out on laminated jute/epoxy (warp and weft direction) under tensile test shows the presence of a considerable gradient of deformation. This gradient is explained by the variability related to the local voluminal change of jute fibers of one place to the other and the nature of the weaving of the jute fiber. The three-point bending tests show a significant dispersion of rupture stress. The thermomechanical tests carried out on samples in the two principal directions, show that the thermal coefficient of expansion in warp direction is 48% larger compared to the weft direction. The thermogravimetric test shows that this laminate absorbs up to 4% water mass after 8 h in a climatic chamber with 70% moisture contentItem Study of mechanical and hygrothermal properties of agglomerated cork(2012) Mir, A.; Bezzazi, B.; Zitoune, R.; Collombet, F.The mode of development of sandwich panels with cork core by the method infusion cannot prevent the resin from penetrating inside cork. This study characterizes white cork agglomerated before and after the development of sandwich panels to see the influence of the resin on the mechanical and hygrothermic characteristics of cork. Two types of cork are considered, they are characterized by their density of 270 kg/m3 (C270) and of 190 kg/m3 (C190). One notes that the modulus of rigidity of C270 cork is 20% larger than that of C190.The presence of resin increases also the module of shearing 47% for C270, 64% for C190. The hygrothermic analysis out of drying oven at 100°C shows a fall of significant mass in the first 7 hours. The analysis thermogravimetry at 220°C, the fall of significant mass is recorded in the first 5 minutesItem Fatigue behaviour of the laminates jute/epoxy(2013) Mir, A.; Aribi, C.; Bezzazi, B.Work presented is interested in the characterization of the quasistatic mechanical properties and in fatigue of a composite laminated in jute/epoxy. The natural fibres offer promising prospects thanks to their interesting specific properties, because of their low density, but also with their bio deterioration. Several scientific studies highlighted the good mechanical resistance of the vegetable fibre composites reinforced, even after several recycling. Because of the environmental standards which become increasingly severe, one attends the emergence of eco-materials at the base of natural fibres such as flax, bamboo, hemp, sisal, jute. The fatigue tests on elementary vegetable fibres show an increase of about 60% of the rigidity of elementary fibres of hemp subjected to cyclic loadings. In this study, the test-tubes manufactured by the method infusion have sequences of stacking of 0/90° and ± 45° for the shearing and tensile tests. The quasistatic tests reveal a variability of the mechanical properties of about 8%. The tensile fatigue tests were carried out for levels of constraints equivalent to half of the ultimate values of the composite. Once the fatigue tests carried out for well defined values of cycles, a series of static tests of traction type highlights the influence of the number of cycles on the quasi static mechanical behavior of the laminate jute/epoxyItem Experimental study for the choice of a matrix epoxy resin for the elaboration of laminates(2013) Aribi, C.; Bezzazi, B.; Mir, A.The performances of composite materials are influenced by the properties of the matrix used. The latter ensures the desired form and the protection of the reinforcements against the external attacks. This work comprises a comparative study between laminates developed with different matrices in epoxy resin. Their characterization has to choose the best matrix able to give best results in static and dynamic tests. The resins used are provided by Granitex Algéria and which are primary Médapoxy STR resins, Médapoxy inject 812 and Médapoxy Al resin. Hence, the results of tensile tests prove a fragility of the AL resin which influences the maximal constraint of traction compared to the STR primary resin. Furthermore, Inject 812 resin shows very limited mechanical properties due to the changes of the epoxy network with the addition of diluents which has significantly decreased its viscosity