Abstract:

Carbon nanotubes (CNT) and nano silicon carbide (n-SiC) gradient layers reinforced aluminum (Al) matrix composite materials have been fabricated by mechanical ball milling followed by hot-pressing. The n-SiC was used as a mixing active agent for dispersing the CNT in the Al powder. The hardness of the produced composites was dramatically increased up to eight times higher than bulk pure Al with increasing the amount of nano-SiC particles. A small quantity of aluminum carbide (Al4C3) was observed by high resolution transmission electron microscopy and relatively quantified usingX-ray diffraction. Beside the enhancement of the composite hardness due to the CNT and the nano-SiC, the Al4C3seems to play also a role. This powder metallurgical gradient layers approach also could be applied to other nano-reinforced composites such as ceramics or complex matrix materials.