Abstract Scope |
Multi-principal component carbide ceramics, or high-entropy carbide ceramics (HECC), are novel and promising materials for extreme environments. The first HECC, (Hf0.2Zr0.2Ta0.2Nb0.2Ti0.2)C, with a single phase rock salt structure, was synthesized by spark plasma sintering (SPS) in 2018. Recently, direct selective laser sintering (SLS) process has been successfully developed for additive manufacturing of high-entropy carbide ceramics (HECC), in which a Yb fiber laser was employed for ultrafast reactive sintering of HECC specimens from a powder mixture of constitute monocarbides. A single-phase non-equiatomic HECC was successfully formed in the 4-HECC specimen with a uniform distribution of Zr, Nb, Hf, Ta, and C. In contrast, a three-layer microstructure was formed in the 5-HECC specimen with five metal elements (Zr, Nb, Hf, Ta and Ti), consisting of a TiC-rich top layer, a Zr-Hf-C enriched intermediate layer, and a non-equiatomic Zr-Ta-Nb-Hf-C HECC layer. |