Showing papers by "Patrick S. Nicholson published in 2002"

Electrical conductivity of a 3Y-TZP/alumina laminate composite synthesized by electrophoretic deposition

Abstract: Electrical conductivity measurements were applied to a 3Y-TZP/alumina laminate composite fabricated by electrophoretic deposition in order to evaluate characteristics of its laminar structure non-destructively. Electrical conductivity of the composite was measured in directions parallel and perpendicular to the alumina layers. The composite showed the electrical properties of 3Y-TZP in the direction parallel to the alumina layers, and those of alumina in the perpendicular direction. Electrical conductivity measurements well reflected the laminar structure of the zirconia/alumina composite.

Single-crystal β″-alumina films

Abstract: This chapter focuses on β "-Alumina (Al 2 O 3) single-crystal films and their preparation, characterization, luminescence, and mechanical composite studies. The chapter deals with film-growth technology. Film preparation involves the generation of alkali vapors and their chemical reactions with sapphire substrates. Sodium (Na)- β "-Al 2 O 3 forms at the expense of the sapphire substrate via chemical reaction with alkali rather than vapor–vapor deposition. The latter has a minor influence on film growth at high temperatures. β "-Al 2 O 3 is a superionic solid electrolyte with interesting optical properties. The β "-Al 2 O 3 crystal lattice accommodates exchanged or doped optically active ions at different and high concentration levels. Cu (I)-doped Na-, K-, barium (Ba)-, and Ag/Na- β" -Al 2 O 3 films are prepared with the use of ion exchange and emission spectra measured under UV excitation. Among the host ions, large polarizability favors blue emission. Luminescence patterning is achieved in β "-Al 2 O 3 single-crystal films by charging in an aqueous electrochemical cell with a designed electrode configuration.