Production of AlCrNbTaTi High Entropy Alloy via Electro-Deoxidation of Metal Oxides

Abstract

High entropy alloys (HEAs) have attracted increasing attention because of their outstanding properties for various applications. During the preparation of HEAs, however, high-purity metals are usually used as raw material, which limits the large-scale application of HEAs. In this work, a simple electrochemical method is demonstrated to achieve homogeneous AlCrNbTaTi HEAs directly from metal oxide mixtures, and meanwhile the cathodic reduction mechanism is discussed. The patterns of both X-ray diffraction and selected area electron diffraction show that the as-prepared AlCrNbTaTi HEAs present body centered cubic structure. Upon electrolysis for 12 h, the oxygen content of the product is similar to 0.6 wt% and the cathodic current efficiency is similar to 46.7%. The results also suggest that the cathodic reduction process obeys a three-phase interline propagation mechanism, with the pellet surface initially metallized. (C) 2018 The Electrochemical Society.