TAPAS

Performances achievable through the use of continuous reinforced composites are today typically acquired and demonstrated. Among these composite materials, it is generally accepted that the use of thermoplastic matrices represents a major advantage because of their low environmental impact (no solvents and no VOCs) and their good behaviour in crash stress (intrinsic ductility). However, the inability to produce parts of complex geometry at controlled cost prevents the use of composite materials for applications in medium to large series. The Project objective is to develop new materials / new processing ways for the production of composite parts based on thermoplastic polymer for the automotive market, in order to meet the demand about lighter structures which become necessary because of new environmental regulations and energy dependence problems. This weight reduction requires the development of high performances parts or component modules, compatible with the requirements of cost and mass production rate. Composite fiber thermoplastics (CFRT) is a technological response to this need, but several problems have to be solved in order to consider the use of such materials. Thus, there are currently no available materials that meet the requirements of processability / performance / cost. Among the different manufacturing processes of composite structures, the consolidation in mold at low pressure (Liquid Composite Molding) present a major interest in the production of parts with complex geometry (non-developable surfaces) with the possibility of integrated functions. The recent development of new thermoplastic polymers with low melt viscosity (based on polyamide chemistry) enables access to these new processing routes, but a number of drawbacks about both the consolidated material and the final part have to be solved. This is the case of thermal transfer, the impregnation at high rate of a given reinforcing structure (deformable perform, with variable permeability), and the control of the polymer crystallization and induced residual stresses (thermal and crystallization volumic variation). The objective of the Project is fully consistent with this approach, and its complexity and character of technological breakthrough requires the use of close collaboration between industrial skills (major Groups and SMEs) and academic experts in their field. We will focus together to : - develop base materials (compatible polymers and reinforcements, polymer viscosity, wettability, crystallinity ...); - optimize the processing conditions (LCM) at lab via an instrumented mold of simple geometry (plate) in a first time; - develop a database modeling and simulation; - validate the models on a real functional piece (3D geometry) to be simulated and processed using a LCM system design; - optimize the technical and economic performance of the developed processing way (positive cost, life cycle analysis, recycling aspect ...). The complementarity of the partners in this consortium must help to realize the breaking science and technology needed to strengthen the position of France in the field of composites by opening the way to medium / large series market.