Planetary ball milling of MWCNTs reinforced NiAl composites

Multi-walled carbon nanotubes (MWCNTs) are remarkable reinforcing material with magnificent mechanical features. The presences of sp² C-C networks in their shells have been responsible for their wide-ranging mechanical abilities. MWCNT are generally known to agglomerate because of the existence of Van der Waals forces, which results in processing challenges during dispersion in metal matrices. In the present study, planetary ball milling (PM 100) was utilized in milling nickel and aluminum powders with equal stoichiometry ratio of 49.5 wt%. Subsequently, planetary ball milling (PM 400) was employed in dispersing 1 wt%-MWCNTs in the milled sample for 1.5 h. The structural damage to the nanotubes was observed using the Raman spectroscopy. Scanning electron microscopy and X-ray diffractometer revealed the morphology and phase changes in the composite respectively. The sintered composite powder was found to have better mechanical property. There was an improvement in the microhardness from 306 to 336 HV_0.1.