Effect of flake-like powder morphology on the microstructure and texture in Mg-Al-RE alloy

Abstract

Wet-milling of magnesium powder was performed at room temperature in ethanol covered by argon atmosphere. It is shown that the wet-milling in ethanol can produce highly deformed powder of flake-like morphology. Subsequently, bulk samples were consolidated by spark plasma sintering technique in the temperature range 400–550 °C. It is shown that milling caused severe microstructural refinement. The flake-like shape of the milled particles was transferred into the compacts and caused formation of a layer-like microstructure which was predominantly perpendicular to the external force applied during sintering. Grain growth was highly limited by powder particles’ interface and secondary phase particles present in the matrix. Formation of texture in the compacts was attributed to the combination of SPS thermo-mechanical effect and continuous static recrystallization acting during the sintering.