Influence of Yb and Si content on the sintering and phase changes of Yb:YAG laser ceramics

Yb-doped yttrium aluminum garnet (Yb:YAG) ceramics were prepared via solid state reaction of oxide powders. The Yb concentration ranged from 0 to 10 at.%. Silicon in the form of tetraethyl orthosilicate (TEOS) was added as a sintering aid in amounts of 0.3 and 0.5 wt.% with respect to the weight of solid. Thermal analyses (high temperature XRD, TG-DSC, dilatometric analyses) were performed on various compositions. Sintering was conducted under high vacuum and clean atmosphere. The influence of TEOS addition and Yb content was observed both in connection with phase transformations in function of temperature, and with microstructure and properties of sintered materials.