Paration of a Nanodispersed Aluminum Hydroxide-Based Binder Used for the Production of Refractory Corundum Ceramics

摘要

The preparation of the rehydrated metastable p phase of alumina with a large specific surface based on domestic aluminum hydroxide is studied in order to develop a method for producing a calcium-free binder (analog of the a-Bond binder produced abroad by the Almatis company for the preparation of corundum refractories with a high thermal stability). Three types of aluminum hydroxide specimens from three enterprises, i.e., obtained from different raw materials and by different methods, are studied. The specimens with a specific surface smaller than -240 m~2/g represented by the η-, χ-, v-, θ-, ρ-, and δ-Al_2O_3 structural modifications are isolated due to "impact" dehydration. The dehydration of Al(OH)_3 under reduced pressures is studied. The product with a phase composition closest to that of the a-Bond binder is obtained under an impact thermal load at 600°C and a rarefaction of 0.01 MPa.