Nuclear radiation effects on the ablation performance of advanced composite heatshield materials

Results are presented from experiments to define the influence of simulated nuclear radiation damage on the ablation response of carbon-phenolic materials. Tests were conducted in a 50 MW arc jet facility. Several damaging methods were used and the effects of material properties were studied. The data were used to refine theoretical models of the ablation response. Effects of nonisothermal thermocouple measurements and material expansion due to outgassing and delamination are included. Results show that the ablation response is critically dependent upon the char layer expansion characteristics and material properties are shown to have a significant influence. The effect of the simulated nuclear damage on the ablation performance of these materials is negligible.