Room-temperature single-step production of ultrafine-grained bulk metallic sheets from Al powder

Abstract

Obtaining fully dense products with high strength in one step at room temperature by powder metallurgy (PM) is generally not possible. However, doing so would reduce manufacturing and energy costs substantially. In this work, we have attempted to achieve this on commercially pure aluminum by utilizing the friction-assisted lateral extrusion process (FALEP) which has the capability of producing sheets from bulk or powder metal in a single step, by applying large shear strain. The texture, microstructure, and mechanical properties of the fully compacted powder sample were examined and compared to the bulk-sheet's properties obtained also by FALEP. The powder-FALEP sample showed a smaller grain size and significantly higher strength. Simulations carried out by the Taylor-type lattice-curvature-based polycrystal model shed light on the texture characteristics of the obtained materials and were in good agreement with the experiments.