Dense ZrB_2-MoSi_2 composite coating fabricated by low pressure plasma spray (LPPS)

摘要

Low pressure plasma spray was applied to fabricate ZrB_2-MoSi_2 composite coatings. Their microstructure and oxidation behavior were characterized and compared with those of the ZrB_2-SiC coatings. The ZrB_2-MoSi_2 coating displayed compact and lamellar microstructure with porosity lower than 5%, where MoSi_2 phase was uniformly distributed in the ZrB_2 matrix. ZrB_2-30 vol% MoSi_2 coating exihibited much better oxidation-resistance at high temperature compared to the ZrB_2-30 vol% SiC coating. It is thought that the fine distribution of sufficient MoSi_2 in the matrix and dense microstructure of the ZrB_2-MoSi_2 coating contributed to its excellent high temperature oxidation-resistance.