Fabrication of high-entropy carbide (TiZrHfTaNb)С by high-energy ball milling

Abstract

Abstract In this study, we report on the process to fabricate powder of high-entropy carbide (TiTaNbZrHf)С. We have obtained a high-entropy carbide phase by two-step high-energy ball milling (HEBM) of metallic precursors and carbon. At the first stage of HEBM, a powder of high-entropy alloy TiTaNbZrHf was prepared. 15 min of HEBM were found to be adequate to converse the initial metallic precursors into a bcc solid solution. High-entropy carbide was fabricated at the second stage of HEBM from TiTaNbZrHf high-entropy alloy and carbon. The formation of the fcc carbide phase under HEBM occurs in two stages within 15–30\xa0min. The first one is reaction diffusion of carbon into a metal matrix forming an intermediate bcc solid solution of TiTaNbZrHf\xa0+\xa0C followed by its second stage where a bcc structure transforms into an fcc one. The fabricated powder of high-entropy carbide (TiTaNbZrHf)С demonstrates thermal stability up to 1200\xa0°C during 6\xa0h.