Fabrication, microstructure, and microhardness of copper composites reinforced by carbon nanotubes

Composites with a copper matrix, reinforced by carbon nanotubes, have been produced by the multistage method including functionalization of carbon nanotubes, their dissolution, mixing with a copper powder, preliminary warm isostatic compaction, and severe plastic deformation by torsion. The microstructure and microhardness of composites containing to 4 wt % of carbon nanotubes have been studied. It has been shown that the matrix grain size after severe plastic deformation significantly decreases, while the internal stress level, dislocation density, and composite microhardness increase with increasing concentration of nanotubes.