High-alumina compounds are reduced with aluminum by applying simultaneous n
itriding. Andalusite, mullite and kaolinite are employed as raw materials.
The sequence of reaction was followed using thermal techniques (ATD-TG-DTG)
and XRD. The reactions that occur are similar for all the aluminosilicates
employed. Silicon and aluminum nitride appear at low temperatures. The fin
al phases are sialon and alumina. (C) 1999 Elsevier Science B.V. All rights
reserved.