ABSTRACT
Abstract. The addition of trace quantities of alwnina to yttria stabilised tetragonal zirconia polycrystal (Y-TZP) leads to enhanced degradation !'llSistance. High spatial resolution EELS measurements were performed on a polycrystalline sample of 3wt% Yz03 - stabilised Zr02 + 0.15wV'/o Ah03; EEL spectra were recorded both on and off grain boundaries. J)istinct EELS evidence for AI was obtained at some, but not all boundaries. AI L2,3-and AI K-edges were recorded and compared to the corresponding spectra obtained from a polycrystalline a-alwnina. The AI K and L2,3-ELNES obtained from the modified Y-TZP grain boundaries show a significant decrease in the relative intensity of the two initial peaks lying within about 10 eV of the edge on-set, as compared to the alwnina spectra suggesting that this may be interpreted as a lower coordination of oxygen to alwniniwn compared with the slightly distorted 6-fold coordination found in a-alumina.
