Egg white as an environmentally friendly low-cost binder for gelcasting of ceramics

Slurries with different solids loading (34-50 vol%) of alumina were made with egg white (ovalbumin)-water premix. The ovalbumin content in the premix was decreased with increase in solids loading to lower slurry viscosity. The slurries were cast into bulk shapes and heated to 80 degreesC, resulting in denaturation of ovalbumin forming a gel. The gelled samples were dried under controlled humidity and sintered in air to densities 94%-97% of theoretical. Alumina slurries formed with egg white (no water) were used to form tapes as thin as 60 mum in the sintered state.