| Excessive firing shrinkage and secondary re-crystallization cannot
be controlled if alumina powder produced from Bayers process
is exclusively used to develop dense alumina body. High
alumina bodies having low firing shrinkage and controlled
microstructure can, however, be developed using alumina powder
from Bayers process and fused alumina grains with MgO in
the form of magnesio-aluminate hydrate (MAH) as sintering
aid. By introducing fine alumina powder pre-calcined at an optimum
temperature, a part of fused alumina grains can be replaced.
The possibility of formation of bodies involving the entire
range of graded fused alumina and fine technical alumina
powder has been explored. |
