Phase Transitions and Oxidation Behavior During Oxyacetylene Torch Testing of TaC–HfC Solid Solutions
Phase Transitions and Oxidation Behavior During Oxyacetylene Torch Testing of TaC–HfC Solid Solutions
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TaC·HfC 固溶体氧乙炔炬测试期间的相变和氧化行为
DOI：
10.1002/adem.202300138
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发表时间：
2023
影响因子：
3.6
通讯作者：
Graeve, Olivia A.
中科院分区：
文献类型：
--
作者：
Sanchez, Maritza;Acord, Katherine A.;Frueh, Samuel;Rueschhoff, Lisa M.;Graeve, Olivia A.
在过渡金属碳化物、硼化物和氮化物中，碳化钽(TAC)和碳化镓(HFC)具有最高的熔化温度，使它们在高速飞行和高温结构应用中具有广阔的应用前景。与纯TAc或HFC相比，TAc和HFC的固溶体具有更强的抗氧化性，因此特别令人感兴趣。研究了Hf含量对TaC-HFC烧结体抗氧化性的影响。采用放电等离子烧结法(2173 K，50 Mpa，10 min)将5种成分制备成块体样品。用氧-乙炔火焰氧化60 S的方法分析了一组成分(100 Vol%Tac、80 Vol%Tac + 20 Vol%HFC和50 Vol%Tac + 50 Vol%HFC)的氧化行为，发现随着HFC含量的增加，TaC-HFC样品的氧化膜厚度减小，质量烧蚀率降低。抗氧化性能的提高可以归因于Hf6Ta2O17相的形成。这一相通过减少氧扩散并作为未氧化材料的保护层来增强抗氧化性。TAC-HFC样品优异的抗氧化性能使这些材料成为高速飞行涂料发展的有力竞争者。
Tantalum carbide (TaC) and hafnium carbide (HfC) have some of the highest melting temperatures among the transition metal carbides, borides, and nitrides, making them promising materials for high‐speed flight and high‐temperature structural applications. Solid solutions of TaC and HfC are of particular interest due to their enhanced oxidation resistance compared to pure TaC or HfC. This study looks at the effect of Hf content on the oxidation resistance of TaC–HfC sintered specimens. Five compositions are fabricated into bulk samples using spark plasma sintering (2173 K, 50 MPa, 10 min hold). Oxidation behavior of a subset of the compositions (100 vol% TaC, 80 vol% TaC + 20 vol% HfC, and 50 vol% TaC + 50 vol% HfC) is analyzed using an oxyacetylene torch for 60 s. The TaC–HfC samples exhibit a reduction in the oxide scale thickness and the mass ablation rate with increasing HfC content. The improved oxidation resistance can be attributed to the formation of a Hf6Ta2O17phase. This phase enhances oxidation resistance by reducing oxygen diffusion and serving as a protective layer for the unoxidized material. The superior oxidation resistance of TaC–HfC samples makes these materials strong contenders for the development of high‐speed flight coatings.