Gelcasting of Alumina-Spinel Refractories
The preparation process of alumina-spinel slurries by using micro-sized alumina-spinel mixtures as raw materials was investigated. The slurries with solids content of 62 vol% and viscosity of 0.3 Pa·s were prepared by adding self-made dispersant ANSP which was a mixture of AN-2000 and STP in mass ratio of 4 to 1. The alumina-spinel refractory was fabricated from the slurries by gelcasting process. The dry parts containing micro-sized alumina-spinel powders with 3.57wt% gel have the highest bending strength of 29.8 MPa and 17.6 MPa with 15:1 AM-MBAM and 4:1 MAM-MBAM respectively. The bending strength enhanced with the increase of reaction temperature. For example, to the 15 wt% 15:1 AM-MBAM gel premix, the bending strength of the parts gelled at 25°C and 55°C were 27.3 MPa and 32.4 MPa respectively. The bending strength also increased with the rising of the amount of monomer.
Wei Pan and Jianghong Gong
K. Q. Liu et al., "Gelcasting of Alumina-Spinel Refractories", Key Engineering Materials, Vols. 368-372, pp. 1149-1151, 2008