碳/碳复合材料的激光烧蚀行为与机制

Laser ablation behavior and mechanism of carbon/carbon composites

碳/碳(C/C)复合材料作为性能优良的耐烧蚀材料得到了广泛的应用,其作为抗激光烧蚀材料的潜力待被发掘。本文制备了不同密度的C/C复合材料,在无氧环境下以CO激光器为光源,探究了高能激光与C/C复合材料之间的作用机制,系统地分析了材料的特性和激光参数不同对烧蚀表现的影响。采用三维轮廓仪对线烧蚀率进行表征。结果表明,随着烧蚀时间或激光功率的变化,C/C复合材料的烧蚀表现均为非线性变化。C/C复合材料的本征特性决定了其热量载荷。密度越高的C/C复合材料,其热量载荷越高,烧蚀性能越好。热量载荷与激光热流密度之间的关系则决定了材料的烧蚀表现,当激光的热流密度大于材料的热流载荷时,烧蚀速率会呈阶跃式攀升。

Carbon/carbon(C/C)composites have been widely used as ablative materials with excellent performance,it has great potential to be used as laser ablation resistant material.In this paper,C/C composites with different densities were prepared.COlaser was used as the heat source to explore the interaction mechanism between high-energy laser and C/C composite material under oxygen-free atmosphere,and systematically analyze the influence of C/C properties and laser parameters on ablation performance.The ablation depth was characterized by 3D profilometer.The results show that the variation of C/C ablation behavior is nonlinear with the change of ablation time or laser power.Intrinsic properties of C/C composites determine the thermal load,which determines the ablative performance of C/C composites.When the laser heat flux is greater than the thermal load of the material,the linear ablation rate will rise drastically.