Synthesis and Research of Aluminum Oxide Additives for Refractory Composite Materials

Hollow Al 2 O 3 microspheres were synthesized by spray pyrolysis and investigated by x-ray phase analysis, scanning and transmission electron microscopy, and low-temperature nitrogen adsorption. The analytical results demonstrate that the aluminum oxide microspheres are hollow. The size of the microspheres varies from 5 to 10 μm. The dependence of the specific surface area and the size of the microspheres on the synthesis temperature was determined. The wall thickness of the microspheres depends on their diameter and varies from 50 to 200 nm. The paper shows the possibility of using microspheres as an additive for refractory castable and products based on them.