Interfacial phenomena in thermally sprayed multiwalled carbon nanotube reinforced aluminum nanocomposite

The interfacial phenomena in thermally sprayed (plasma and high-velocity oxyfuel spraying) hypereutectic Al-Si composite with multiwalled carbon nanotube (MWCNT) reinforcement have been analyzed both theoretically and experimentally. The formation of an ultrathin β-SiC reaction layer at the interface is confirmed. Plasma sprayed composite exhibits a thicker SiC layer (∼5 nm) than the high-velocity oxyfuel sprayed composite (∼2 nm). The presence of SiC layer formation is also corroborated in a chemical vapor deposition experiment where Si was deposited on MWCNTs. The formation of β-SiC is responsible for the improved wettability of the molten Al-Si alloy matrix with MWCNT reinforcement.