Ex situ Al-Al2O3 ultrafine grained nanocomposites produced via powder metallurgy

Commercial purity aluminum powder and Al2O3 nano-particles were ground by high energy ball milling in order to embed and disperse the ceramic phase in the soft metal matrix. The composite powders were consolidated by ECAP. SEM and EBSD analysis were performed to investigate the microstructure of metal matrix and the distribution of reinforcement. The specific powder metallurgy route proposed in this work revealed to be an effective method for the production of ex situ ultra-fine grained matrix nano-composites characterized by homogeneous dispersion of discrete nano-particles and by improved hardness.