Loss Mechanism of Rare-Earth Tungsten Cathode Applied to High-Temperature Electrostatic Precipitation

Abstract:

Rare-earth tungsten thermionic emission material was used in the high-temperature electrostatic dust removal technology. A static test facility was self-designed to explore the emission characteristic. XRD, SEM and EDS were used to analyze the microstructure and element distribution. Working in high-temperature and oxidizing condition, tungsten in the thermionic emission materials is oxidized to tungsten trioxide, but the rare-earth tungstate in the grain boundary has no chemical changes. In high-temperature and oxidizing ambience, there is oxidation and volatilization on the surface of rare-earth tungsten, resulting in materials loss. The degree of loss depends on the composition of gas.

• Periodical: Advanced Materials Research (Volumes 113-116)
• Pages: 908-912
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.113-116.908
• Online since: June 2010
• Authors: Jin Jin Xu, Zhong Zhu Gu, Xiao Li Xi, Wei Min Dai, Juan Juan Liu
• Keywords: Cathode Loss, Microstructure, Rare Earth Tungsten, Thermionic Emission

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