Densification during hot-pressing of carbon nanotube-metal-magnesium aluminate spinel nanocomposites

Alain Peigney (1) , Sébastien Rul (1) , F. Lefèvre-Schlick (1) , Christophe Laurent (1)

1 CIRIMAT - Centre interuniversitaire de recherche et d'ingenierie des matériaux

The densification by hot-pressing of ceramic-matrix composites containing a dispersion of carbon nanotubes (CNT), mostly single-walled, is studied for the first time. Fifteen different CNT-Co/Mo-MgAl2O4 composite powders containing between 1.2 and 16.7 vol.% CNT were prepared by catalytic chemical vapour deposition. The in situ growth of CNT within the oxide powder made it possible to obtain a highly homogeneous distribution of CNT. Low contents of CNT (up to 5 vol.%) are beneficial for the first shrinkage step (up to 1100 ◦C), dominated by the rearrangement process, while higher contents are detrimental. At higher temperatures (1100-1300 ◦C), CNT clearly inhibit the shrinkage, and this detrimental effect regularly increases with the CNT content. Several explanations are proposed, in relation with the particular mechanical properties of CNT and their highly connected web-like distribution within the material.

Mots clés: Hot pressing; Nanocomposites; Spinels; Carbon nanotubes

Domaines: Matériaux

Alain Peigney, Sébastien Rul, F. Lefèvre-Schlick, Christophe Laurent. Densification during hot-pressing of carbon nanotube-metal-magnesium aluminate spinel nanocomposites. Journal of the European Ceramic Society, 2007, vol. 27, pp. 2183-2193. ⟨10.1016/j.jeurceramsoc.2006.07.012⟩. ⟨hal-00807834⟩