Production of Al–20 wt.% Al2O3 composite powder using high energy milling

High energy ball milling was used to produce a nanostructured Al matrix composite reinforced by submicron α-alumina particles. Scanning electron microscopy analysis as well as tap and green density measurements were used to optimize the milling time needed for the completion of the mechanical milling process. Results show that addition of alumina particles as the reinforcement has a drastic effect on the size, morphology and pressability of the powder. Scanning electron microscopy shows that distribution of alumina particles in the Al matrix reaches a full homogeneity after steady state. This would increase the hardness of powder due to a nano-structured matrix and oxide dispersion strengthening.

The effect of milling time and addition of alumina powder on the morphology, structural evolution and steady state time of Al was investigated. Presence of alumina particles has a considerable effect on the structural properties of Al during milling and reduces steady state time.Figure optionsDownload as PowerPoint slide