Tribological properties of hot-pressed alumina–CNT composites

Carbon nanotubes (CNTs) have lately attracted remarkable attention as reinforcements of materials because of their exceptional mechanical and electronic properties. However, studies on the ceramic–CNT composite have been rarely reported. Alumina–CNT composites have been produced to investigate the effect of carbon nanotube addition on the mechanical and tribological properties by hot-pressing. The alumina–CNT composite powder was prepared by catalytic pyrolysis of acetylene gas with an iron nitrate impregnated alumina. The contents of iron nitrate were controlled from 0 to 0.5 mol.% to change the CNT compositions in the alumina–CNT composite. The microstructures and mechanical properties of hot-pressed composites have been investigated to explain the effect of the CNT compositions on the tribological properties of the alumina reinforced with CNT composites.