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This paper introduces the preparation method and characterization results of TiB 2 ceramics with CoCrFeNiAl high-entropy alloy (HEA) as a sintering aid by Spark Plasma Sintering (SPS). Good wettability between HEA and TiB 2 was proved by the sessile drop method, indicating promising prospects for this composite. The sintering results showed that the addition of HEA could dramatically promote the sinterability of TiB 2 . TiB 2 -5 wt. % HEA dense ceramics prepared at the optimal temperature of 1650 • C showed fine morphology without formation of brittle phases. The liquid phase in the ceramics was highly consistent with the so-called "supra-nano-dual-phase materials (SNDPM)", with near-ideal strength. This study represents the first time that a ceramic-SNDPM composite has been fabricated since the invention of such structures.

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In the study, an equiatomic CoCrNiCuZn high-entropy alloy (HEA) was prepared by mechanical alloying (MA) and the phases, microstructures, and thermal properties of the alloy powder were explored. The results suggest that a solid solution with body-centered cubic (BCC) phase and a crystalline size of 10 nm formed after 60 h of milling. Subsequently, the alloy powder was consolidated by spark plasma sintering (SPS) at different temperatures (600 °C, 700 °C, 800 °C, and 900 °C). Two kinds of face-centered cubic (FCC) phases co-existed in the as-sintered samples. Besides, Vickers hardness and compressive strength of the consolidated alloy sintered at 900 °C were respectively 615 HV and 2121 MPa, indicating excellent mechanical properties.

Zirconium carbide (ZrC) ceramic is one of the most important and promising materials with a high melting point. However, its low diffusion coefficient affects its densification behavior, which dramatically limits its engineering application. For polycrystal ceramic materials, sintering by thermal diffusion is the most widely used method for consolidation. But in view of the difficult densification behavior of ZrC, it is necessary to develop new sintering methods together with another driving force. In the study, we reported an ultra-high-pressure sintering strategy to fully densify ZrC ceramic under 1.7 GPa at 1600°C. The sintered sample exhibited high density, fine grain size, excellent mechanical properties, and a large number of crystal defects, including dislocation networks and walls, which were similar to those in deformed metals. Its hardness increased to 2057.44 HV0.1 because of its unique microstructure.

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