GDR CNRS 2024
Multiscale Mechanics of fibrous media

The optimization of processing tools and manufacturing procedures are key issues for the development of high-performance biocomposite materials. In this study, we investigated the manufacturing of commingled flax/polypropylene fabrics by fast induction-heated compression moulding to produce lightweight thermoplastic biocomposites. The processing/microstructure/mechanical behaviour relationships of these biocomposites were established based on a careful characterisation of material’s microstructure through SEM and X-ray tomography. Elastic properties of the biocomposites could be maintained even at high processing temperature, but their strength was drastically decreased due to extensive fibre degradation and formation of macro-pores. An optimised set of processing parameters was found for an improved microstructure with limited porosity and fibre degradation. The use of fast induction-heated systems can thus be an interesting solution to overcome the thermal degradation processes occurring with natural fibres reinforced biocomposites, hence opening the doors for the use of higher melting point polymer matrices.