Reactive flash spark plasma sintering of high-entropy ultrahigh temperature ceramics

SCRIPTA MATERIALIA

卷:170

Article

Gild, Joshua¹  Kaufmann, Kevin²  Vecchio, Kenneth^1,2  Luo, Jian^1,2 

[1] Univ Calif San Diego, Program Mat Sci & Engn, La Jolla, CA 92093 USA

[2] Univ Calif San Diego, Dept NanoEngn, La Jolla, CA 92093 USA

关键词: High-entropy ceramics;    Spark plasma sintering;    Ultrahigh temperature ceramics;    Borides;    Carbides;   

DOI  :  10.1016/j.scriptamat.2019.05.039

来源: Elsevier

【 摘 要 】

A new Reactive Flash Spark Plasma Sintering (ReaFSPS) method has been developed to synthesize high-entropy ultrahigh temperature ceramics (UHTCs), using (Hf0.2Zr0.2Ta0.2Nb0.2Ti0.2)B-2 and (Hf0.2Zr0.2Ta0.2Nb0.2Ti0.2)C as examples. X-ray diffraction, energy dispersive X-ray spectroscopy, and electron backscatter diffraction collectively show the formation of a single high-entropy phase within similar to 2 min. Notably, adding 3 wt.% of carbon can promote the formation and homogenization of a high-entropy diboride phase without aggressive mechanical alloying, achieving a >99% relative density. This work has established a new rapid and potentially scalable method to use ReaFSPS to synthesize homogenous high-entropy UHTCs from commercial powders of individual constituents. (C) 2019 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

【 授权许可】

Free