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This paper focuses on the numerical simulation of the polypropylene / multi-walled carbon nanotubes (PP/MW CNT) flow into a twin screw mixer, during the mixing phase. The PP/MW CNT behavior obeys an innovating Carreau law enriched temperature built on the rheological properties carried out previously. The polypropylene was mixed with different MW CNTs contents (1, 2, 4 and 8 wt% of MW CNT content) and the rheological tests were performed at shear rate ranges from 10-1 to 2 10 4 s-1 at four temperatures (180, 200, 220 and 240°C). Thus the effects of the temperature and the MW CNTs content on the rheological properties of the PP/MW CNT composites were investigated. The finite element (FEM) analysis of the PP/MW CNT flow allows to compute the velocity, the shear rate and the temperature during the mixing phase period. A good agreement between the experimental measured torque on the screw and the calculated one is shown. Therefore, one can consider that the physical flow is generally well described, awaiting a numerical simulation of the PP/MW CNT mixing phase.

A finite element simulation is proposed for the shaping of glass fiber fabric. The overall mechanical behavior of the fabric is obtained by combining the tensile behavior of a single thread and the current position of threads in the fabric. The constitutive model for a single thread in tension is based on a statistical approach and is identified using tensile tests. Shear and tensile tests have been carried out on fabric specimens to demonstrate that the behavior of the fabric mainly results from the contribution of each thread, the sliding between fiber threads having a small effect on the energy for the deformation mechanism of these fabrics. A numerical model for the shaping process is obtained based on a finite element approach using three‐ and four‐node membrane shell elements. The formulation accounts for the large displacements and large strains involved in the process as well as the mechanical behavior. A drawing simulation is presented in the case of an hemispherical punch. The comparison with experimental results obtained in this case shows good agreement.

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in order to have high ultimate material properties and a good corrosion resistance. This paper concerns the effect of processing con-There are several authors who have investigated from ditions in metal injection moulding on the resultant experiments the role of process parameters on the final properties of produced parts. A multicavities mould properties of the components5,6 through the different has been designed and manufactured in the laboraprocess stages. The main results show that adapted sintering tory for performing experiments on 316L based feedcycles have to be developed to obtain the best mechanical stock. A set of experiments covering injection properties. moulding, debinding, and sintering stages have beenIn order to develop the proposed methodological realised, investigating the main role of the process analysis, a five cavity mould has been designed and parameters. The properties of the produced parts are manufactured to carry out this research work. This mould analysed through SEM observations, mass measureis equipped with pressure and temperature sensors to ments, and tensile and bending mechanical tests. The measure and control the necessary parameters. All necessary modelling and numerical simulation of the injection parameters are verified and determined to analyse their moulding stage has been developed based on a influence on the injected parts. The research is then biphasic flow approach of the feedstock mixture. The conducted throughout the debinding and sintering stages powder volume fraction is considered as a key varito obtain the final parts with excellent quality. The able to describe phase segregation during moulding microstructures after each stage are verified by SEM and allows powder contours to be found after the observations and the mechanical properties of the final injection stage. Finally the mechanical properties of parts are investigated by tensile and bending experiments. the parts are measured and identified. An inverseThe injection stage is perhaps the most important one. identification procedure combining experiments and All defects appearing in this stage, such as jetting, bubble simulation permits the results to be checked. and phase segregation, etc., will be certainly amplified in PM/0926 all the next stages.7 The modelling of the fluid particle flows has been considered by several methods. The granular Dr T. Barriere and Professor J. C. Gelin are in media mechanics8,9 calculate the motion of each particle in the Applied Mechanics Laboratory, University of the fluid. Powder characterisation, as grain size and Franche-Comte ´and CNRS, 24 Chemin de l'Epitaphe, distribution, can be taken into account, but this method, 25000 Besancon, France. Professor B. Liu is taking of account the evolution of each particle, does not with Southwest Jiaotong University, Institute of allow the modelling of the industrial problems. Several Engineering Science, 610031 Chengdu, Sichuan, authors10,11 use a fluid with an equivalent viscosity but People's Republic of China but is currently a...

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