TEM exploration of in-situ nanostructured composite coating fabricated by plasma spraying 8YSZ-Al-SiC composite powder

Abstract

A novel in-situ synthesis method, which introduced 8YSZ-Al-SiC reaction system to atmospheric plasma spraying process, was put forward to prepare ZrC composite coating. Phase transformation between 8YSZ and 15YSZ caused by in-situ reactions was observed. Efforts were focused on TEM investigation in order to explore in-situ generated microstructure containing nanosized ZrC, ZrSi 2 and 15YSZ grains in the composite coating. Moreover, the relationship between the mechanical properties and microstructure of the ZrC composite coating was preliminarily established based on the micron-indentation test. Results confirmed the feasibility of preparing ZrC composite coating by plasma spraying 8YSZ-Al-SiC composite powder and further proved the positive effect of in-situ generated microstructure of the ZrC composite coating on its mechanical properties.