EUROPEAN CONGRESS AND EXHIBITION ON ADVANCED MATERIALS AND PROCESSES - EUROMAT 2021

Preparation techniques of reinforced composite materials that include nanostructured phases such as carbon nanotubes need a characterization tool that quantifies the degree of homogenization of the nanophase embedded in the composite. Homogenization is a critical aspect during the manufacturing because the presence of aggregates is a major problem for the mechanical performance of the resulting composite as they play the role of structural defects instead of contributing to increase the toughness. This is the case for ceramic materials reinforced with CNTs, in which, typically, aggregates of the nanophase can be observed. Thus, the reinforcing strategy of composites by adding CNT has not been sufficiently exploited yet, and is currently limited to very low carbon contents. This work aims to help the fabrication protocols in order to better manufacture ceramic matrix composites with maximized mechanical properties.
Given the size of CNTs (nm - µm), techniques such as SAXS or SANS can help to characterize this problem of inhomogeneity in the manufacturing processes, as they explore just this range of typical sizes. Thus, a computational tool is being developed to identify how the differences in the dispersion degree of CNTs in the small-angle scattering experiments are revealed. Firstly, the computational tool has been tested with fully-known hierarchical structural models in order to confirm the adequate identification of the existing characteristic sizes of the structures. Then, several spatial arrangements of CNTs are built, and their scattering curves will be obtained. That is, the “scattering signature” of the CNT distributions with different degrees of homogeneity, from the individually dispersed nanotubes to large aggregates, will be identified. Contrasting the set of simulation curves with experimental results could help to identify the correct preparation of nanostructured composites.