Fig. 1.

SEM images of raw materials of Cu, Ti₃SiC₂, C, MWCNT, and graphene powders after ball milling, taken at a low magnification (b) and a high magnification (a, c, d). a–c Nanocomposites with 0.5 wt% graphenes and 0.5 wt% MWCNTs. d Nanocomposites with 0.8 wt% graphenes and 0.2 wt% MWCNTs