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With the aim of damage modeling in long fiber composite structures during drilling, a simplified framework of study is adopted with the choice of orthogonal cutting. This study consists of two parts. The first is related to the experimental analysis of the orthogonal cutting applied to unidirectional laminates in carbon/epoxy for various angles between the direction of fibers and the tool cutting direction (cutting speed). The second part concerns the numerical modeling of the orthogonal cutting in statics for the simple case of fibers orientated at 0° with respect to the tool’s cutting direction. The experimental study of the cut highlights the great influence of the angle between the fiber orientation and the direction of cutting speed of the tool on the chip formation as well as the rupture modes. Numerical computation is based on the fracture process and more particularly on the computation of the energy release rate by the method Virtual Crack Extension (using the software, SAMCEF). It makes it possible to measure the influence of the geometry of the cutting tool and the depth of the cut on the cutting force.

A pulsed Nd:YAG laser combined with a thermogravimetric cell has been used to spall in situ the oxide films grown on a Fe–2.25Cr–1Mo steel at high temperature in oxidizing media. This technique allows to define the oxidation rate of bare metal surfaces, which can be used to simulate the corrosion-dominated regime during slurry–erosion tests.

CASTEM is a general purpose finite element software for the solution of mechanical and heat transfer analysis for the linear or non-linear problems. It has been developed since 10 years jointly by the mechanical and thermal research department (DEMT) of the French Atomic Energy Commission (CEA) and the CISI which commercializes this system. The CASTEM system is based on the very extensive experience acquired by the CEA engineers, in the main problems encountered in the nuclear industry. This capabilities are continuously upgraded by the mechanical testing sessions performed at the CEA, mainly for the purpose of development and validation of the computational schemes.

CASTEM is a general purpose finite element software for the solution of mechanical and heat transfer analysis for the linear or non-linear problems. It has been developed since 10 years jointly by the mechanical and thermal research department (DEMT) of the French Atomic Energy Commission (CEA) and the CISI which commercializes this system. The CASTEM system is based on the very extensive experience acquired by the CEA engineers, in the main problems encountered in the nuclear industry. These capabilities are continuously upgraded by the mechanical testing sessions performed at the CEA, mainly for the purpose of development and validation of the computational schemes.

The tortoise is an animal the Gbaya hunt during three months of the wet saeson. It can be kept in captivity for two or three months. It is cooked and eaten by men only. It is a highly esteamed and valued dish that can be reserved for special occasion.s. It occupies an important place in Gbaya symbolism and is also a cunning and intelligent character in tales; La tortue est un gibier expressément recherché pendant trois mois en saison des pluies. Elle peut ensuite être gardée en captivitée deux ou trois mois. C'est une nourriture d'homme que les femmes ne consomment pas. Ce sont les hommes qui la préparent et la consomment. Très appréciée, elle constitue un mets de choix pouvant être offert dans certains circonstances. Elle est très investie sur le plan symbolique et est aussi un personnage rusé et intelligent des contes.