Synthesis of zirconium carbide whiskers by a combination of microwave hydrothermal and carbothermal reduction
Abstract
Zirconium carbide (ZrC) whiskers were successfully synthesized by a combination of microwave hydrothermal (MH) and carbothermal reduction. The precursors of ZrC whiskers were produced by MH, subsequently carbothermally reduced to ZrC whiskers at 1100-1600 °C in an Ar atmosphere. Effects of the reduction temperature and precursors with various carbon/zirconium (C/Zr) molar ratios on the synthesis of ZrC whiskers were investigated. The results showed that the carbothermal reduction occurred at 1100 °C, and terminated at a relatively low temperature (1400 °C). When the reduction temperature was 1500 °C and the C/Zr molar ratio was 5:1, the ZrC whiskers with the largest aspect ratio and the most uniform distribution were produced. The whiskers exhibited the diameters of 0.1-2 μm and the lengths of 5-30 μm. The synthesized ZrC whiskers with a single crystalline phase displayed cylindrical and pagoda-like morphologies. The growth of ZrC whiskers was considered to be governed by the Ostwald ripening and S-L-S mechanism.
- Publication:
-
Journal of Solid State Chemistry France
- Pub Date:
- February 2018
- DOI:
- 10.1016/j.jssc.2017.11.002
- Bibcode:
- 2018JSSCh.258..383L
- Keywords:
-
- ZrC whiskers;
- Microwave hydrothermal;
- Carbothermal reduction;
- Growth mechanism