Research Progress on the Preparation and Characterization of Ultra Refractory TaxHf1-xC Solid Solution Ceramics

doi:10.15541/jim20200440

Abstract

Abstract:

Ta_xHf_1-xC(0<x<1) solid solution ceramics, a series of solid solutions of tantalum carbide (TaC) and hafnium carbide (HfC) over the whole range of composition, have been considered as promising candidates for many important applications which can tolerate temperature above 3000 K due to their high melting points (> 4000 K), high hardness (~ 30 GPa), low coefficient of thermal expansion, excellent oxidation resistance, and excellent ablation resistance. Over the past decades, some extreme conditions required for aerospace industry have greatly promoted the development of Ta_xHf_1-_xC materials, and dozens of literatures were published in this area. In this paper, the research progress of Ta_xHf_1-_xC solid solution ceramics was introduced in terms of powder synthesis techniques, densification methods and mechanism, mechanical properties at room temperature, thermophysical properties, oxidation and ablation resistance. Advantages and disadvantages of three common techniques (solid solution between metal carbides, carbonization reaction of metals, and carbothermal reduction of metal oxides) for synthesizing Ta_xHf_1-_xC powder as well as the difficulties in densification of Ta_xHf_1-_xC solid solution ceramics were analyzed. Influence of sintering process on microstructure and mechanical properties at room temperature of Ta_xHf_1-_xC solid solution ceramics was discussed briefly. The hardness, elastic modulus, K_IC, melting point, thermal conductivity, coefficient of thermal expansion, oxidation and ablation behavior of Ta_xHf_1-_xC solid solution ceramics with different Ta/Hf ratios were summarized. It revealed that Ta_xHf_1-_xC solid solution ceramics will obtain a good performance on both mechanical properties and oxidation resistance when Ta/Hf was approximate 1. Furthermore, the remaining challenges and future outlook of Ta_xHf_1-_xC solid solution ceramics were also addressed.

Key words: TaC, HfC, ultra-high temperature, solid solution ceramics, extreme thermal environment, review

CLC Number:

TQ174

XIAO Peng, ZHU Yulin, WANG Song, YU Yiping, LI Hao. Research Progress on the Preparation and Characterization of Ultra Refractory Ta_xHf_1-_xC Solid Solution Ceramics[J]. Journal of Inorganic Materials, 2021, 36(7): 685-694.

Figures/Tables 9

References 62

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	Solid solution between metal carbides	Carbonization reaction of metals	Carbothermal reduction of metal oxides
Advantages	Easy to operate; products have high purity and could achieve densification simultaneously	High temperature is not necessary; the whole process lasts only several seconds, not time consuming	Easy to operate; raw materials are cheap; have potential to synthesize single-phase products with fine grain size at relatively low temperature
Disadvantages	Needs high temperature and long time; products are not single-phase solid solution with elements uneven distribution	The reaction process are unable to control; products are usually not pure	The phase and microstructure of products are closely related to the distribution and binding state of oxides and carbon

	Solid solution between metal carbides	Carbonization reaction of metals	Carbothermal reduction of metal oxides
Advantages	Easy to operate; products have high purity and could achieve densification simultaneously	High temperature is not necessary; the whole process lasts only several seconds, not time consuming	Easy to operate; raw materials are cheap; have potential to synthesize single-phase products with fine grain size at relatively low temperature
Disadvantages	Needs high temperature and long time; products are not single-phase solid solution with elements uneven distribution	The reaction process are unable to control; products are usually not pure	The phase and microstructure of products are closely related to the distribution and binding state of oxides and carbon

	Raw powder	Sintering method	Relative density/%	Hardness/GPa	Elastic modulus/GPa	K_IC/(MPa·m^1/2)	Ref.
Ta_0.9Hf_0.1C-12vol% MoSi₂	TaC, HfC, MoSi₂	SPS	100.0	(15.0±0.2)	—	(3.2±0.3)	[26]
Ta_0.9Hf_0.1C-12vol% TaSi₂	TaC, HfC, TaSi₂	SPS	100.0	(15.9±0.3)	—	(3.3±0.2)	[26]
Ta_0.87Hf_0.13C	TaC, HfC	HIP	>98.0	24.1	575.4	—	[3]
Ta_0.8Hf_0.2C	Ta_0.8Hf_0.2C	HP	99.6	(30.3±1.6)	(462.5±3.1)	(2.2±0.4)	[30]
Ta_0.8Hf_0.2C	Ta_xHf_1-_xC	HP	94.4	27.2	491.7	3.0	[21]
Ta_0.8Hf_0.2C	TaC, HfC	SPS	97.8	(16.7±0.9)	(443.2±23.7)	(4.6±1.1)	[40]
Ta_0.8Hf_0.2C	TaC, HfC	SPS	(97.7±0.1)	(19.3±1.3)	(459.0±5.8)	(2.9±0.9)	[32]
Ta_0.8Hf_0.2C-10vol% MoSi₂	TaC, HfC, MoSi₂	SPS	99.8	(18.5±0.5)	(482.0±2.0)	(4.2±0.2)	[29]
Ta_0.8Hf_0.2C-12vol% MoSi₂	TaC, HfC, MoSi₂	SPS	100.0	(15.2±0.5)	—	(3.9±0.2)	[26]
Ta_0.8Hf_0.2C-12vol% TaSi₂	TaC, HfC, TaSi₂	SPS	100.0	(17.7±0.4)	—	(3.2±0.1)	[26]
Ta_0.75Hf_0.25C	TaC, HfC	HIP	>98.0	28.6	567.7	—	[3]
Ta_0.7Hf_0.3C-12vol% MoSi₂	TaC, HfC, MoSi₂	SPS	97.8	(15.9±0.6)	—	(3.9±0.1)	[26]
Ta_0.7Hf_0.3C-12vol% TaSi₂	TaC, HfC, TaSi₂	SPS	98.9	(18.2±0.7)	—	(2.8±0.1)	[26]
Ta_0.67Hf_0.33C	Ta_0.67Hf_0.33C	HP	95.3	29.7	483.0	2.5	[21]
Ta_0.5Hf_0.5C	Ta_0.5Hf_0.5C	HP	99.2	(36.7±1.2)	(559.3±6.5)	(2.9±0.4)	[30]
Ta_0.5Hf_0.5C	Ta_0.5Hf_0.5C	HP	97.9	37.9	591.0	2.5	[21]
Ta_0.5Hf_0.5C	TaC, HfC	SPS	98.2	(17.1±1.1)	(523.8±7.0)	(6.0±0.7)	[40]
Ta_0.5Hf_0.5C	TaC, HfC	SPS	(95.7±0.3)	(22.1±1.8)	(549.0±11.2)	(2.9±0.7)	[32]
Ta_0.5Hf_0.5C	TaC, HfC	HIP	>97.0	23.5	469.9	—	[3]
Ta_0.3Hf_0.7C	HfO₂, Ta₂O₅, graphite	SPS	98.7	(20.0±0.9)	—	(5.2±0.2)	[48]
Ta_0.25Hf_0.75C	Ta_0.25Hf_0.75C	HP	96.5	(29.9±2.2)	(436.4±13.8)	(2.2±0.2)	[30]
Ta_0.25Hf_0.75C	TaC, HfC	HIP	>98.0	29.1	593.5	—	[3]
Ta_0.2Hf_0.8C	Ta_0.2Hf_0.8C	HP	95.9	(35.1±1.1)	(554.7±8.8)	(2.3±0.5)	[21]
Ta_0.2Hf_0.8C	TaC, HfC	SPS	(87.0±0.2)	(16.7±3.0)	(438.0±17.8)	(3.4±0.6)	[32]
Ta_0.2Hf_0.8C	TaC, HfC	SPS	98.8	(19.1±0.3)	(577.3±6.0)	(5.5±0.6)	[40]
Ta_0.2Hf_0.8C	HfO₂, Ta₂O₅, graphite	SPS	100.0	(19.7±0.7)	—	5.1	[48]
Ta_0.17Hf_0.83C	TaC, HfC	HIP	>98.0	26.6	534.2	—	[3]
Ta_0.1Hf_0.9C	HfO₂, Ta₂O₅, graphite	SPS	99.3	(19.7±0.8)	—	—	[48]

	Raw powder	Sintering method	Relative density/%	Hardness/GPa	Elastic modulus/GPa	K_IC/(MPa·m^1/2)	Ref.
Ta_0.9Hf_0.1C-12vol% MoSi₂	TaC, HfC, MoSi₂	SPS	100.0	(15.0±0.2)	—	(3.2±0.3)	[26]
Ta_0.9Hf_0.1C-12vol% TaSi₂	TaC, HfC, TaSi₂	SPS	100.0	(15.9±0.3)	—	(3.3±0.2)	[26]
Ta_0.87Hf_0.13C	TaC, HfC	HIP	>98.0	24.1	575.4	—	[3]
Ta_0.8Hf_0.2C	Ta_0.8Hf_0.2C	HP	99.6	(30.3±1.6)	(462.5±3.1)	(2.2±0.4)	[30]
Ta_0.8Hf_0.2C	Ta_xHf_1-_xC	HP	94.4	27.2	491.7	3.0	[21]
Ta_0.8Hf_0.2C	TaC, HfC	SPS	97.8	(16.7±0.9)	(443.2±23.7)	(4.6±1.1)	[40]
Ta_0.8Hf_0.2C	TaC, HfC	SPS	(97.7±0.1)	(19.3±1.3)	(459.0±5.8)	(2.9±0.9)	[32]
Ta_0.8Hf_0.2C-10vol% MoSi₂	TaC, HfC, MoSi₂	SPS	99.8	(18.5±0.5)	(482.0±2.0)	(4.2±0.2)	[29]
Ta_0.8Hf_0.2C-12vol% MoSi₂	TaC, HfC, MoSi₂	SPS	100.0	(15.2±0.5)	—	(3.9±0.2)	[26]
Ta_0.8Hf_0.2C-12vol% TaSi₂	TaC, HfC, TaSi₂	SPS	100.0	(17.7±0.4)	—	(3.2±0.1)	[26]
Ta_0.75Hf_0.25C	TaC, HfC	HIP	>98.0	28.6	567.7	—	[3]
Ta_0.7Hf_0.3C-12vol% MoSi₂	TaC, HfC, MoSi₂	SPS	97.8	(15.9±0.6)	—	(3.9±0.1)	[26]
Ta_0.7Hf_0.3C-12vol% TaSi₂	TaC, HfC, TaSi₂	SPS	98.9	(18.2±0.7)	—	(2.8±0.1)	[26]
Ta_0.67Hf_0.33C	Ta_0.67Hf_0.33C	HP	95.3	29.7	483.0	2.5	[21]
Ta_0.5Hf_0.5C	Ta_0.5Hf_0.5C	HP	99.2	(36.7±1.2)	(559.3±6.5)	(2.9±0.4)	[30]
Ta_0.5Hf_0.5C	Ta_0.5Hf_0.5C	HP	97.9	37.9	591.0	2.5	[21]
Ta_0.5Hf_0.5C	TaC, HfC	SPS	98.2	(17.1±1.1)	(523.8±7.0)	(6.0±0.7)	[40]
Ta_0.5Hf_0.5C	TaC, HfC	SPS	(95.7±0.3)	(22.1±1.8)	(549.0±11.2)	(2.9±0.7)	[32]
Ta_0.5Hf_0.5C	TaC, HfC	HIP	>97.0	23.5	469.9	—	[3]
Ta_0.3Hf_0.7C	HfO₂, Ta₂O₅, graphite	SPS	98.7	(20.0±0.9)	—	(5.2±0.2)	[48]
Ta_0.25Hf_0.75C	Ta_0.25Hf_0.75C	HP	96.5	(29.9±2.2)	(436.4±13.8)	(2.2±0.2)	[30]
Ta_0.25Hf_0.75C	TaC, HfC	HIP	>98.0	29.1	593.5	—	[3]
Ta_0.2Hf_0.8C	Ta_0.2Hf_0.8C	HP	95.9	(35.1±1.1)	(554.7±8.8)	(2.3±0.5)	[21]
Ta_0.2Hf_0.8C	TaC, HfC	SPS	(87.0±0.2)	(16.7±3.0)	(438.0±17.8)	(3.4±0.6)	[32]
Ta_0.2Hf_0.8C	TaC, HfC	SPS	98.8	(19.1±0.3)	(577.3±6.0)	(5.5±0.6)	[40]
Ta_0.2Hf_0.8C	HfO₂, Ta₂O₅, graphite	SPS	100.0	(19.7±0.7)	—	5.1	[48]
Ta_0.17Hf_0.83C	TaC, HfC	HIP	>98.0	26.6	534.2	—	[3]
Ta_0.1Hf_0.9C	HfO₂, Ta₂O₅, graphite	SPS	99.3	(19.7±0.8)	—	—	[48]