Relationship between color changes and ternary eutectic reaction in Yb/Y-co-doped SiAlON ceramics

Abstract

This study investigated the relationship between the green/brown colors and Yb/Y-co-doped ternary eutectic reactions. A color difference was initially observed at 1600 °C. The green color indicates a relatively highly porous area compared to the brown color, and it was confirmed that the green color was spherical in all samples. This difference in color was analyzed through photoluminescence (PL), and it was confirmed that the reduction of Yb2+ increased at temperatures higher than 1550 °C owing to the reducing atmosphere generated by the carbon ambient. The reaction sequence of the phase formation of SiAlON exhibited a difference resulting from the reduction in Yb ions, and the sequence of phase formation improved with an increase in the content of Y substituted for Yb.