Colloidal processing and ionic conductivity of fine-grained cupric-oxide-doped tetragonal zirconia

CuO-doped tetragonal ZrO2 (3-mol%-Y2O3-doped tetragonal zirconia, 3Y-TZ) gr een bodies were consolidated from zirconia slurries with Cu2+ by a pressure filtration method. The slurries were prepared by dispersing 3Y-TZ powder i n a solution of [NH4OH + NH3NO3] = 0.1 M at pH 11 and adding an appropriate amount of Cu(NO3)(.)3H(2)O solution. Green bodies with narrow pore-size di stribution were obtained after cold isostatically pressing the pressure-fil trated bodies. Small amounts of CuO-doped samples were densified fully at 1 200 degreesC. The size of a grain of 0.16-mol%-CuO-doped 3Y-TZ sintered at 1200 degreesC was 84 nm. Bulk and grain-boundary conductivities are measure d by a complex impedance method. The bulk conductivity of the CuO-doped 3Y- TZ was almost equal to the undoped one, but the grain-boundary conductivity decreased with CuO addition.