Preparation of translucent alumina ceramic specimen using slip casting method

Abstract

A commercial alumina nanopowder has been applied to prepare high density alumina ceramic specimens using a simple slip casting method. Slurry preparation process is one of important steps to enhance density and optical property of alumina specimens to be fabricated. In this work, the effect of the amount of ammonium salt of poly(methacrylic) acid dispersant and polyvinyl alcohol binder in alumina suspension on the slurry viscosity was discussed. Green body with relative density higher than 55% could exhibit homogenous appearance when a certain ratio of dispersant to binder is employed. The fully dense translucent alumina compact consisting of submicron grain could be fabricated by atmospheric sintering at 1350°C with soaking time of 3600 s and further HIP-sintering at 1300°C for 7200 s in argon atmosphere.