Feasibility of Synthesising Lightweight Nanophase Al Materials by Mechanical Alloying

The current research is aimed at producing kilogram quantities of Al nanomaterials derived from mechanically alloyed (MA) and atomized precursors. Although MA is a time intensive process, it gives bulk quantities of fine powders featuring a smaller grain size (14 nm or less) than found in atomized material. Consolidation was achieved at 350 C by HIP/forge and extrusion methods but produced grain growth; despite this growth, MAed materials remained more than 40 pct harder than atomized specimens, which was attributed to a fine grain structure (less than 160nm diameter) in the former material. (Author)