Cr-assisted low-temperature densification of (Ti,Zr,Nb,Ta,Mo)C high-entropy carbides with ultrafine grain and enhanced hardness

Abstract

While the use of low-melting-point metals as sintering aids for high-entropy carbide (HEC) ceramics has been well-established, their existence can compromise hardness due to residual metallic inclusions. This study demonstrates an innovative strategy to meet this challenge, where (Ti, Zr, Nb, Ta, Mo)C high-entropy carbide ceramics with ultrafine grain and enhanced hardness are obtained through Cr-metal-assisted spark plasma sintering at a temperature as low as 1600 ℃.