Research Progress of High-entropy Carbide Ultra-high Temperature Ceramics

doi:10.15541/jim20230562

Abstract

Abstract:

The development of high-speed flight technology has put forward an urgent demand for high- performance thermal structure materials. High-entropy carbides (HECs) ceramics are a fast-emerging family of materials that combine the excellent properties of high-entropy ceramics and ultra-high temperature ceramics. HECs have a broad application prospect in extreme service environments, which has received extensive attention from scholars in recent years. Compared with traditional ultra-high temperature carbides containing only one or two transition metal elements, HECs have a greater potential for development because of their improved comprehensive performance and greater designability of composition and properties. After successive exploration of HECs in recent years, researchers have obtained many interesting results, developed a variety of preparation methods, and gained comprehensive understanding of microstructure and properties. The basic theories and the laws on HECs obtained from experimental process are reviewed in this paper. Preparation methods of HECs including powders, blocks, coatings and films, as well as fiber-reinforced HECs-based composites are summarized. Research progress on the properties of HECs, such as the mechanical properties, thermal properties, and especially the oxidation and ablation resistance related to high-temperature applications, is reviewed and discussed. Finally, the scientific issues that need to be further explored in this area are emphasized, and the prospects are proposed.

Key words: high-entropy carbide, ultra-high temperature ceramic, mechanical property, oxidation resistance, ablation resistance, review

CLC Number:

TQ174

CAI Feiyan, NI Dewei, DONG Shaoming. Research Progress of High-entropy Carbide Ultra-high Temperature Ceramics[J]. Journal of Inorganic Materials, 2024, 39(6): 591-608.

Figures/Tables 14

References 152

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Synthesizing method	Composition (lattice parameter)	Starting materials	Synthesizing conditions	Grain size	Oxygen content/ % (in mass)
Mechanical alloying^[32-33]	(TiZrHfVNb)C (0.4496 nm) (TiZrHfVTa)C (0.4495 nm) (TiZrHfNbTa)C (0.4526 nm) (TiZrVNbTa)C (0.4440 nm) (TiHfVNbTa)C (0.4425 nm) (ZrHfVNbTa)C (0.4493 nm)	Transition metals + Graphite powder	50-70 h	2.5 nm 2.4 nm 3.3 nm 4.0 nm 3.2 nm 3.0 nm	-
Carbothermal reduction method^[34-35]	(TiZrHfNbTa)C (0.4524 nm)	Metal oxides + Graphite powder or carbon black	Carbothermal reduction (CTR) 1600 ℃, 1 h; Solid solution (SS) 2000 ℃, 1.5 h	550 nm	0.2
Carbothermal reduction method^[34-35]	(TiZrHfNbTa)C (0.4503 nm)		2200 ℃, 1 h	0.5-2 μm	-
Molten salt synthesis^[36]	(TiVNbTa)C (0.4468 nm)	Metal carbides + Molten salt media KCl	1300 ℃, 1 h	50-110 nm	-
Liquid precursors method^[37-38]	(TiZrHfNbTa)C (-)	Metal chlorides + Furfuryl alcohol	CTR 1400 ℃, 1 h; SS 2000 ℃, 1 h	132 nm	0.22
Liquid precursors method^[37-38]	(TiZrHfTa)C (0.4529 nm)	Equiatomic metal containing monomers + Allyl-functional novolac resin	1800 ℃, 2 h	~100 nm	-
Direct synthetic method^[39]	(TiZrHfNbTa)C (0.4508 nm)	Metal carbides	1950 ℃, 5 min (SPS)	~2 μm	-

Synthesizing method	Composition (lattice parameter)	Starting materials	Synthesizing conditions	Grain size	Oxygen content/ % (in mass)
Mechanical alloying^[32-33]	(TiZrHfVNb)C (0.4496 nm) (TiZrHfVTa)C (0.4495 nm) (TiZrHfNbTa)C (0.4526 nm) (TiZrVNbTa)C (0.4440 nm) (TiHfVNbTa)C (0.4425 nm) (ZrHfVNbTa)C (0.4493 nm)	Transition metals + Graphite powder	50-70 h	2.5 nm 2.4 nm 3.3 nm 4.0 nm 3.2 nm 3.0 nm	-
Carbothermal reduction method^[34-35]	(TiZrHfNbTa)C (0.4524 nm)	Metal oxides + Graphite powder or carbon black	Carbothermal reduction (CTR) 1600 ℃, 1 h; Solid solution (SS) 2000 ℃, 1.5 h	550 nm	0.2
Carbothermal reduction method^[34-35]	(TiZrHfNbTa)C (0.4503 nm)		2200 ℃, 1 h	0.5-2 μm	-
Molten salt synthesis^[36]	(TiVNbTa)C (0.4468 nm)	Metal carbides + Molten salt media KCl	1300 ℃, 1 h	50-110 nm	-
Liquid precursors method^[37-38]	(TiZrHfNbTa)C (-)	Metal chlorides + Furfuryl alcohol	CTR 1400 ℃, 1 h; SS 2000 ℃, 1 h	132 nm	0.22
Liquid precursors method^[37-38]	(TiZrHfTa)C (0.4529 nm)	Equiatomic metal containing monomers + Allyl-functional novolac resin	1800 ℃, 2 h	~100 nm	-
Direct synthetic method^[39]	(TiZrHfNbTa)C (0.4508 nm)	Metal carbides	1950 ℃, 5 min (SPS)	~2 μm	-