Preparation of A Thermoelectric Composite of AgSbTe_2/Ag_2 Te by Mechanical Alloying

摘要

Synthesis of AgSbTe_2/Ag_2Te composite by mechanical alloying from elemental powders is described. Mechanical alloying was done by vibratory ball milling with a ball-to-powder ratio of 100 : 1. The studied composition range was Sb_2Te_3 - xmol percent Ag_2Te (x = 43 approx 70); the (beta + Ag_2Te) region in the Sb_2Te_3 - Ag_2Te phase diagram. XRD analysis showed that after sufficient milling beta compound AgSbTe_2 was found to be formed for x = 43. The composites of various compositions were formed depending on the initial mixing ratios. The sintered compacts of the mechanically alloyed powders had homogeneous composite microstructures and exhibited the increase in the connectivity of the second phase Ag_2Te in the AgSbTe_2 matrix with increase in the Ag_2Te content.