Development of environmental barrier coatings using novel flash sintering technique

The feasibility of using contactless flash sintering for the first time to densify Yb-silicate coatings on ceramic substrates was explored, focusing on optimising the process by varying electrical currents. EDS and XPS analyses were conducted on samples sintered at 80 mA, 90 mA, and 120 mA. The results indicate that at 80 mA, the Yb2O3 coating densifies without forming Yb-silicate. Increasing the current to 90 mA leads to the formation of Yb2Si2O7, while at 120 mA, Yb2SiO5 begins to form, resulting in a coating with both Yb-monosilicate and Yb-disilicate. This study also demonstrated that CFS can oxidise samples, enabling thicker Yb-silicate coatings with a fraction of a time compared to traditional sintering methods.