Gel‐casting of MgAl2O4 transparent ceramics using a common dispersant

Abstract The ethanolaminic salt of citric acid (commercial name Dolapix CE 64) has commonly been used as a dispersant for colloidal based ceramic forming process. In this paper, a surprise was presented that MgAl 2 O 4 spinel slurries consisting of MgAl 2 O 4 spinel nanoparticles and Dolapix CE 64 gelled in air at room temperature spontaneously. The MgAl 2 O 4 spinel slurries with high solid loading (54 vol%) were prepared with Dolapix CE 64 and the green body with up to 57% relative density was obtained. MgAl 2 O 4 transparent ceramics with small grain size (0.92 μm) and high transmittance (81.7% at 600 nm) were fabricated after pre‐sintering at 1500°C and hot‐isostatic sintering at 1550°C.