Quantitative Analyses of MWCNT-Ti Powder Mixtures using Raman Spectroscopy: The Influence of Milling Parameters on Nanostructural Evolution

Carbon nanotubes (CNTs) are considered as promising reinforcements for metal matrix composites because of their unique mechanical and thermal properties. High energy ball milling (HEBM) via powder metallurgy has emerged as an effective technique to disperse CNTs in metal powder matrices. Despite the effectiveness in dispersion, HEBM under harsh milling conditions may damage the CNTs. In this study, a planetary ball mill has been employed to disperse 0.5 wt% multi‐walled carbon nanotubes (MWCNTs) into a titanium (Ti) powder matrix. The results indicated that harsh ball milling conditions created non‐sp2 defects in MWCNTs. In‐situ formation of TiC depended upon the milling parameters and milling environment. Harsh ball milling conditions create structural disorders such as non‐sp2 defects in the form of open edges and vacancies in the C–C system of multi‐walled carbon nanotubes (MWCNTs). These open edges (existing along the side walls) and vacancies provide potential sites for the formation of interfacial reaction products of titanium carbides (TiC).