Permeable Porosity of Refractory Castables Evaluated by the Water-Expulsion Porosimetry Technique

In this work, the water‐expulsion porosimetry technique was used to quantify the permeable pores of self‐flow ultralow‐cement refractory castables that were treated at 600°–1650°C. Results have shown that the method as proposed in previous works was not valid, because water was not removed continuously from pores, relative to increased pressure. Nevertheless, the maximum pore diameter obtained according to ASTM Method E128‐89 could be successfully correlated with other castable physical properties (such as the permeability constants from the Forchheimer equation) and the apparent porosity obtained via the Archimedes technique. Although the apparent porosity decreased as the thermal treatment temperature increased, the pore morphology changed continuously, with the generation of less‐tortuous and more‐permeable paths for fluid flow.