Experimental Study on Combustion Characteristics for Polyurethane-aluminum Composite Insulation Material under Different Heat Fluxes

The decorative materials with external insulation release a large amount of smoke and heat in fires, and cause severe hazard and losses to human beings and properties. In this paper, the combustion characteristics of polyurethane-aluminum composite material, including ignition time, heat release rate, mass loss rate, concentration of gas components and other parameters, are studied and analyzed under six different heat fluxes, namely 25, 30, 35, 40, 45 and 50 kW/m2, with cone calorimeter to investigate the combustion performance of the material. The results show that the heat release rate reaches a minimum value under a flux of about 30 kW/m2. The curve trends of CO and CO2 concentrations, mass loss rate and heat release rate over time are similar, whereas the concentration of O2 changes inversely. Based on the experimental data, the classic formula between ignition time and radiation heat flux of thermally thick material can be used to predict the pyrolysis process of polyurethane-aluminum composite materials successfully, but the critical heat flux cannot be predicted.