To control the SiO2/Al2O3 ratio in a starting clay material for the synthesis of β′-sialon by the carbothermal nitridation process, montmorillonite was pillared with Al2O3. Conversions to sialon of pillared clay (31% Al2O3) and reference unpillared montmorillonite (18% Al2O3) have been compared. Pillared montmorillonite yielded a mixture of β′-sialon and various oxynitrides and oxycarbides of alumina as intermediate products. Pillared clay transformed faster during annealing than structural components of smectite alone. For the proper thermal treatment and clay/carbon ratio, both pillared and unpillared clays resulted in β′-sialon solid solutions.
All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Mechanics of Materials
- Mechanical Engineering