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The mechanical behavior of aluminum alloy under impact loading using different configurations is described. Perforation tests are referred in this work at wide ranges of specimen using several projectile shapes to analyze their effect on the ballistic curve VR -V0 (conical, hemispherical and blunt), with a diameter of 6.mm. A wide range of impact velocities from 40 to 100 m/s has been used. Experimental and numerical analysis have been carried out to predict the mechanical behavior of the studied aluminum alloy. This analysis has been done using a high-pressure gas gun. Specimens have been prepared from standard 1.0 mm and 1.5 mm thick aluminum sheets with 13x13 cm plates. The resistance and the energy absorbed by the aluminum sheets under dynamic load have been obtained by measuring the initial and residual velocities of the projectiles. The experimental and numerical results are presented and compared in terms of ballistic curve VR -V0, and a good correlation is observed between the two types of results.

Composite materials are attracting increasing interest from many industrial sectors, and their use is becoming more widespread. The naval industry, for example, remains a large field of investigation for composite materials due to their mechanical properties, able to reach very interesting performance levels. Composites are often composed of plies arranged according to loading directions and forming structures called laminates; these directions can have a great effect on the structural behavior of the composite. For this, the study carried out in this article, consists in determining orientations and stacking sequences effect on the mechanical performance of a glass/epoxy composite panel, with a thickness of 8 mm containing 12 plies of the same thickness and different orientations, inclined at an angle of 10° and impacting the water at a velocity of V = 8 m/s.

Since carbon nanotubes and carbon fibers were discovered, the number of research works on these composite materials has exploded, and that’s the reason behind using them in this article as reinforcement to improve the mechanical, electrical and thermal behaviors of materials, to enable their use as Nano-sensors in several new applications. This article aims to describe the structure of these materials and their multi-functionality. An analytical estimation of physical properties was presented, using the homogenization technique. Then, a numerical study in Abaqus, to determine thickness and volume fraction effect of CNts on the behavior of composite materials.

International audience; The structural design of spars for horizontal axis wind turbine blades to achieve satisfactory levels of performance starts with the knowledge of aerodynamic forces acting on the blades. The present paper proposes a comparative study of the geometries of three spars designed for a 48 m long composite blade. The spars are evaluated under compression, bending loads as well as on free vibration. Different Subroutines have been developed and coupled with Finite Element Analysis (FEA) software to analyze the mechanical performances and the qualities of each one of the three designed spars. In other words, it seeks not only to define the behavior and response of each one of the spars and the effect of composite materials on the improvement of the structure stiffness and weight, but also to determine the suitable spars type for the wind turbine blade and the results shows that the Box spars offers a compromise of the main parameters.