Optimization of ball-milling process for preparation of Si-Ge nanostructured thermoelectric materials with a high figure of merit

We report on the thermoelectric properties of nanostructured SiGe alloys which are well known to be reliable materials at high temperatures. Our aim was to optimize the synthesis parameters in order to simplify the manufacturing process. Here we show that 1 h ball milling process followed by consolidation of the mechanically alloyed nanopowders by spark plasma sintering is sufficient to prepare an n-type nanostructured SiGe bulk sample with a high figure of merit ZT similar to 4.1 at 800 degrees C. (C) 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.