Influence of Addition of Various Fillers on Char Expansion of Fire-Retardant Intumescent Coatings for Steel Structures

When steel reaches temperatures above 500 ℃ during accidental fires, it loses its mechanical strength. Fire safety of steel structures is one of the important factors to consider when designing construction infrastructure because it can save human lives and valuable property. An Intumescent coating acts as a protective layer on the steel structures at high temperatures, as it produces a carbonaceous char on reaction to fire. The char layer formed acts as insulation during fire accidents, protecting the steel structures physically and thermally. The coating composition is formulated to produce an effective carbonaceous char. An Intumescent coating is made up of fire-retardant additives and fillers combined with a binder and a solvent. The incorporation of fire-retardant fillers in the coating composition results in a variety of alterations to the produced char layer, including increased fire resistance, altered char layer growth rate, and strengthened char structure. This chapter presents the char expansion results that occur when various fillers are added to water-based fire-retardant Intumescent coating compositions.