The effect of LaSi2 content on the powder characteristics and coating structure of ZrB2-SiC

Abstract

To investigate the effect of LaSi2 content on the properties of ZrB2-SiC composite powder and coatings, different amounts of LaSi2 were added to the ZrB2-SiC system. The composite powders were prepared using the induction plasma spheroidization process, and the coatings were fabricated using atmospheric plasma spraying. Results showed that LaSi2 significantly improves the density of both the powder and the coatings. As LaSi2 content increase to 15 vol%, the density of the powders increases to 2.75 g/cm3 and the porosity of the coatings decreases to 6.92 %. Our results suggest that LaSi2 can fully melt in the plasma jet field and act as a sealing phase to heal pores, thereby improving the performance of both the powders and subsequently, the coatings.