Chemical stability of carbon nanotubes in the 2024Al matrix

Five volume percent of carbon nanotubes and 2024Al alloy powder were mixed with ball milling method, and then the composite was fabricated at 873 K by hot pressing sintering technique. The microstructure of the composite was investigated using optical microscopy, transmission electron microscopy, and X-ray diffraction. The experimental results showed that carbon nanotubes are reacted and changed into Al4C3. Nano-Al4C3 phases with needle shape are distributed mainly on Al grain boundaries; meanwhile some of them exist within Al grains. The reaction mechanism of carbon nanotubes-Al is discussed.