The addition of polymeric fibers in the refractory castables formulation is a well-known technique to reduce the risks of explosive spalling during the drying steps. Fibers are believed to be able to promote permeability increase, allowing an easier release of pressurized steam of the castable structure. Authors' previous works described same of the factors that can affect its performance, such as volumetric content, type and fiber length. Up to now, the way this permeability increase affects the drying behavior was not explored in a systematic way. In this work, a mechanism for the fibers performance was proposed, based on the correlation among the magnitude of the permeability generated, the temperature range it occurs, the thermal characterization of the polypropylene fibers and the dehydration kinetics of the castable.
refractory castables; drying; permeability; polymeric fibers