Influence of ZrB2 Nanoparticles on the Mechanical and Thermal Behaviors of Carbon Nanotube Reinforced Resol Composite

The present study focuses on the thermal response of carbon ?ber-reinforced phenolic composites, where the matrix has been modi?ed with different reinforcements. Two types of materials, multiwalled carbon nanotubes and zirconium diboride（ZrB2）, were used in a new design of mixture to produce the heatresistant ablative composite system. The CNT/ZrB2/carbon/phenolic nanocomposite（Z/NT-CR） system corresponding to CNT/carbon/phenolic nanocomposite（NT-CR） showed a reasonable decrease in mass loss and the ablation rate as compared to carbon/phenolic composite（CR）. However, substantial drop in two factors was found for Z/NT-CR as compared to carbon/phenolic and NT-CR. Ablation mechanisms for all three composites were investigated by thermal gravimetric analysis in conjunction with microstructural studies using a ?eld emission scanning electron microscope. The microstructural studies revealed that CNTs acted as an ablation resistant phase for protection against 2000 °C, and the conversion from ZrB2 to Zr O2 played an important role as an insulator in the performance of char layer in the ablation resistance.