为研究复合材料的热解问题，设计了氮气流保护条件下的低功率密度辐照实验，获得了不同辐照时间和不同功率密度下碳纤维环氧树脂复合材料层合板的热解规律。实验结果表明：试样质量损失随辐照时间持续呈单调增大趋势，但热烧蚀率却逐渐减小并有稳定趋势；试样质量损失与功率密度呈线性关系；激光功率密度的增加可提高热烧蚀率，但随功率密度的增加，试样热烧蚀率增幅减小并有饱和趋势。

In order to study the pyrolysis of composites, an experimental investigation of carbon fiber reinforced epoxy resin composites was carried out. The samples, protected by tangential nitrogen flow, were subjected to a lower power density laser. The influence laws of laser irradiation time and power density on the pyrolysis of composites were obtained and discussed. The results reveal that, along with the laser irradiation time increase, the mass loss of samples increases monotonically while the thermal ablation rate of samples decreases gradually and will tend to be steady. On the other hand, the mass loss of samples is proportional to the laser power density. However, the thermal ablation rate increases significantly at first along with the power density increase, and then slowly since it enters into the glacis.