Grain Boundary Structure and Solute Segregation in CuO Doped 3 mol% Yttria Stabilized Zirconia

The microstructure of the grain boundaries and solute segregation are studied for 0.3 mol%CuO doped 3 mol% yttria-stabilized zirconia (3Y-TZP) using TEMs equipped with EDS and EELS . The observations revealed grain boundaries of various thickness ranging from a sharp boundary without any extra phase to those with amorphous-like phase, of up to 2 nm thickness in between. There were also pockets filled with amorphous-like phase at the triple junctions of grain boundaries. Segregation of Cu and Y were observed not only in these amorphous-like regions but also along sharp grain boundaries without any extra phase.