超高熔点TaxHf1-xC固溶陶瓷的制备工艺与性能研究进展

doi:10.15541/jim20200440

摘要/Abstract

摘要：

Ta_xHf_1-_xC固溶陶瓷是碳化钽(TaC)和碳化铪(HfC)在一定条件下以任意比例形成的系列固溶体, 其熔点普遍在4000 K以上, 最高可达4300 K, 且硬度高、模量高、热导率低、抗高温氧化和抗烧蚀性能优异, 具备在极端热环境(>3000 K)下服役的潜力, 成为耐超高温材料领域的研究热点和前沿。本文综述了近年来Ta_xHf_1-_xC固溶陶瓷在粉体合成技术、致密化工艺和机理、室温力学性能、热物理性能、抗氧化性能、抗烧蚀性能等方面所取得的研究进展, 分析了Ta_xHf_1-_xC固溶陶瓷粉体不同合成技术的优劣及致密化的难点, 讨论了Ta_xHf_1-_xC固溶陶瓷组成、结构和性能之间的相互关系。此外, 本文还指出了Ta_xHf_1-_xC固溶陶瓷目前存在的挑战, 并对未来潜在的发展方向作了展望。

关键词: TaC, HfC, 耐超高温, 固溶陶瓷, 极端热环境, 综述

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

中图分类号:

TQ174

肖鹏, 祝玉林, 王松, 余艺平, 李浩. 超高熔点Ta_xHf_1-_xC固溶陶瓷的制备工艺与性能研究进展[J]. 无机材料学报, 2021, 36(7): 685-694.

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.

图/表 9

参考文献 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]