Mechanical properties of Al-Mg/MWCNT nanocomposite powder produced under different parameters of ball milling process

Abstract

In this study, the effects of multi-wall carbon nanotubes (MWCNTs) and the ball milling process parameters on the structure of the AlMg alloy powders have been studied. For this purpose, three different composite powders have been synthesized through the ball-milling process at different times and milling rates. The microstructural and phase analyses have been carried out via scanning electron microscopy (SEM), field emission scanning electron microscopy (FESEM), and X-ray diffraction (XRD) spectroscopy, respectively. The results indicate that increasing time and speed of the ball-milling process leads to the formation of finer particles, which consequently intensifies the plastic deformation and results in a smaller crystallite size, and the results indicated that the amount of crystal size decreased by almost 83%. The morphological investigations indicate that in lower milling rates, the MWCNTs are agglomerates and increasing milling rate and time results in improving the distribution of the MWCNTs, decreasing nanotubes' length, and promoting their diffusion into the AlMg matrix. Furthermore, the formation of AlMg intermetallic phases through the ball-milling process of the composite powders has also been confirmed via microstructural investigations.