Fabrication of CrSi₂ Thermoelectric Material Using Mechanical Alloying

Abstract

Elemental powders of chromium and silicon have been mixed to give the desired composition of Cr-66.66 at%Si and milled in a planetary ball mill under an argon atmosphere. CrSi₂ has been synthesized in situ during ball milling. The obtained powder milled for 360ks consisting nano-sized Cr, Si and CrSi₂ enables us to prepare dense compacts at the consolidating temperature 1290K which is about 170K lower than that of the other milled powders for various times. This is due to a decrease of powder particles and grains. Power factor of Cr-66.66 at%Si compact prepared by mechanical alloying and pulse current sintering is higher than that of other silicides below 650K, and shows the maximum value of 1.4×10_-3 (W⋅K_-2⋅m_-1) at 550K.