Abstract
Aluminum nanocomposites containing 30 vol%Al2O3 were produced by severe plastic deformation using high-pressure torsion (HPT). HPT was conducted at room temperature under a pressure of 6.0 GPa for disk samples (Disk-HPT) and 3.0 GPa for ring samples (Ring-HPT). For comparison, an alternate rotation (Cyclic-HPT) was also adopted to check any difference in the microstructural development. Ring-HPT showed a more uniform dispersion of Al2O3 particles in the Al matrix and higher hardness values than those obtained by Disk-HPT. Agglomeration of Al2O3 particles was observed for any condition of HPT but the agglomerates were smaller in size, less in volume and more finely distributed in Ring-HPT than in Disk-HPT.