Review: carbon nanotube dispersal mechanisms in the fabrication of powder metallurgy metal matrix composites and effects on mechanical properties

Optimizing powder metallurgy methods: Effects of carbon nanotube dispersal mechanisms on mechanical properties of aluminium/carbon nanotube composites

“…In this study, SWCNTs are not subjected to a functionalization procedure, as previous studies have shown the process to be too aggressive completely destroying their tubular motif. 9 SEM analysis was carried out using a FEI Quanta 3D Field Emission Gun SEM/focused ion beam instrument. Energy dispersive spectroscopy (EDS) analysis was also carried out using this SEM instrument, as this gives a qualitative picture of aluminium oxide growth formed during curing of composite powders.…”

“…8 However, in a comprehensive review previously carried out by the authors of this study, research carried out in the fabrication (via PM methods) and mechanical characterization of CNT/MMCs within the past couple decades, a broad range of mechanical properties are reported using various nanotube dispersion techniques. 9 Furthermore, researchers report different mechanical properties using the same nanotube dispersion technique in reinforcing the same metal system. 9 Therefore, the authors of this study find it necessary to investigate the synergetic effect of CNT surface functionalization and combinations of nanotube dispersion techniques in optimizing mechanical performances and microstructure of Al/CNT nanocomposites.…”

“…9 Furthermore, researchers report different mechanical properties using the same nanotube dispersion technique in reinforcing the same metal system. 9 Therefore, the authors of this study find it necessary to investigate the synergetic effect of CNT surface functionalization and combinations of nanotube dispersion techniques in optimizing mechanical performances and microstructure of Al/CNT nanocomposites.…”

“…11 A diverse set of mechanical properties have been measured and reported by different research teams for the same metal composite materials incorporating CNTs. 9 Typical CNT dispersal mechanisms in the fabrication of CNT/MMCs via PM methods are wet process (surfactant assisted), mechanical milling, hand grinding, mechanical stirring, ultrasonication, electroless deposition (plating), in situ chemical vapour deposition, molecular-level mixing and other novel dispersal mechanisms. 9 Some researchers have explored the use of surfactants (wet process) to exfoliate CNT bundles into individual tubes.…”

“…9 Typical CNT dispersal mechanisms in the fabrication of CNT/MMCs via PM methods are wet process (surfactant assisted), mechanical milling, hand grinding, mechanical stirring, ultrasonication, electroless deposition (plating), in situ chemical vapour deposition, molecular-level mixing and other novel dispersal mechanisms. 9 Some researchers have explored the use of surfactants (wet process) to exfoliate CNT bundles into individual tubes. With regard to their use in the dispersion of CNTs within a matrix medium, two important qualities of surfactants are useful.…”