Transparent, luminescent terbium doped zirconia: development of optical-structural ceramics with integrated temperature measurement functionalities

We present a method for the preparation of transparent Tb doped zirconia (Tb:ZrO2) ceramics that luminesce in the visible. The visible luminescence is temperature dependent, yielding samples that have integrated temperatures sensing capabilities. Our approach is to simultaneously react and densify ZrO2 and Tb4O7 using current activated pressure assisted densification (CAPAD). The Tb dopant serves to both stabilize the tetragonal phase of zirconia and for emitting light. The Tb:ZrO2 ceramics have an excellent combination of structural and optical properties; the toughness is comparable to yttria stabilized zirconia and the transparency in the visible is high. Moreover, the luminescent lifetimes are long and amenable to luminescent thermometry. The ceramics have promise as thermal barrier materials and high-strength windows with “built-in” temperature measurement capabilities.