Effect of Glass-Fabrics and High-Melting Powder Fillers on Thermal Protective Properties of Thermosetting Laminates

The present work investigates the ablative and thermal properties of phenol formaldehyde glass-fabrics laminates filled with mixtures of corundum Al₂O₃ and carbon C powders. The laminates specimens of dimensions 10x25x35 mm were treated with hot combustion gases having a temperature of more than 2800ºC. The carbonization of the thermosetting matrix was observed. Statistical methods for planning experiments were used, and the effect of components on the average rate of ablation, the maximum back side temperature of specimen and the average mass waste under intensive heat flow after 30 s of treatment with hot combustion gases was established. The best thermal protective properties were exhibited by the laminate containing 30% matrix, 25% fibre glass-fabric reinforcement, 9% corundum, and 36% carbon powder.