Slip casting of sialon for pressureless sintering

The properties of aqueous slips of sialon were studied. Ammonium polyacryla te was used as a deflocculant. It was shown that the apparent viscosity for slips with solid content 40 vol % was low and the slip resulting from this is almost Newtonian. This slip proved sufficiently fluid for casting. Howe ver, the apparent viscosity for slips with solid content 45 vol % increased significantly. The slips resulting from this exhibited dilatant flow and w ere difficult to cast. The viscosity, fluidity, and pH of the slips were st udied and tiles were cast and fired in nitrogen at 1740 degrees C for 3 h t o a bulk density of 3.20 g cm(-3). (C) 1998 Kluwer Academic Publishers.