研究最高熔化温度材料：TaC-HfC 体系的激光熔化研究。

Investigating the highest melting temperature materials: A laser melting study of the TaC-HfC system.

机构信息

Centre for Advanced Structural Ceramics, Department of Materials, Imperial College London, South Kensington, London, SW7 2AZ, UK.

European Commission, Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, D-76125 Karlsruhe, Germany.

出版信息

Sci Rep. 2016 Dec 1;6:37962. doi: 10.1038/srep37962.

DOI:10.1038/srep37962

PMID:27905481

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC5131352/

Abstract

TaC, HfC and their solid solutions are promising candidate materials for thermal protection structures in hypersonic vehicles because of their very high melting temperatures (>4000 K) among other properties. The melting temperatures of slightly hypostoichiometric TaC, HfC and three solid solution compositions (TaHfC, with x = 0.8, 0.5 and 0.2) have long been identified as the highest known. In the current research, they were reassessed, for the first time in the last fifty years, using a laser heating technique. They were found to melt in the range of 4041-4232 K, with HfC having the highest and TaC the lowest. Spectral radiance of the hot samples was measured in situ, showing that the optical emissivity of these compounds plays a fundamental role in their heat balance. Independently, the results show that the melting point for HfC, (4232 ± 84) K, is the highest recorded for any compound studied until now.

摘要

TaC、HfC 及其固溶体由于其极高的熔点（高于 4000K）等特性，是高超音速飞行器热防护结构的有前途的候选材料。略微亚化学计量的 TaC、HfC 和三种固溶体组成（TaHfC，x=0.8、0.5 和 0.2）的熔点长期以来被认为是已知的最高熔点。在当前的研究中，它们首次使用激光加热技术重新进行了评估，时间跨度长达五十年。结果表明，它们的熔点在 4041-4232K 范围内，其中 HfC 的熔点最高，TaC 的熔点最低。原位测量了热样品的光谱辐射，表明这些化合物的光学发射率在其热平衡中起着基本作用。此外，结果表明，HfC 的熔点（4232±84）K 是迄今为止所研究的任何化合物中记录到的最高熔点。