Fluorescence and time-resolved spectra of ZTA ceramics

Two sets of high density zirconia-toughened aluminas (ZTA) are investigated by photoluminescent techniques. The luminescence response of the ceramics can be understood primarily on the basis of a mixed luminescence from the zirconia and alumina components. Possible effects of microstructure and impurities on the luminescence of zirconia components are discussed mainly in terms of internal damage related to toughening mechanisms and to differences in the nature of grain boundaries. Luminescence decays and time-resolved spectra of Cr3+ emissions upon excitation with light of different wavelengths are performed at room temperature. Most details of the emission and excitation spectra are consistent with the predictions of crystal field theory for Cr3+ ions in alumina host. (C) 1997 Elsevier Science Ltd.