Structure and thermal characterization of expanded intumescent coatings for fire protection

摘要

Laboratory-scale mass-loss cone tests have been conducted on water-based intumescent coating that is designed for structural steel fire protection. Thermal insulating performance was measured for coating samples with various initial thicknesses under four constant incident heat fluxes (25, 50, 75, and 100 kW/m~2). Morphological characteristics of expanded char layers were studied using a computer tomography-based analytical method. The porosity distribution in the vertical direction was determined using ImageJ software. Thermal characteristic of expanded char layer was analyzed using differential scanning calorimetry (DSC) and dynamic plane source (DPS) methods. The specific heat capacity and apparent thermal conductivity were measured in the vertical direction of the expanded char layer. The thermal performance data obtained from the radiant cone exposure tests were correlated with the structure and thermal characteristics of intumescent coating for different initial thicknesses and incident heat fluxes.