Density, Porosity, and Permeability
Density of dense castables follows a simple trend—as the alumina content of the
base aggregate(s) increases, so does density since higher-alumina raw materials
are also denser. Particle sizing and packing also will influence density with
castables based on ordered sizing being denser than materials based on random
sizing. Porosity, on the other hand, does not depend as much on aggregate as it
does on sizing, with gap sized systems having the lowest porosity and random
systems having the higher porosities.