激光辐照碳纤维的冲量耦合特性研究

Impulse Coupling Characteristics of Carbon Fiber Irradiated by Pulsed Laser

本文对空间碎片材料碳纤维的冲量耦合特性进行了实验研究。设计了脉冲激光烧蚀光斑尺寸测量分析方法,测量获得了不同激光能量下的烧蚀光斑尺寸。基于扭摆微冲量测量原理,测量纳秒激光烧蚀碳纤维T300的冲量,研究结果表明,在能量密度达到6 J/cm2之前,冲量和冲量耦合系数均迅速增加,当能量密度达到6 J/cm2后,由于等离子体屏蔽效应的影响,冲量增加变缓,而冲量耦合系数逐渐下降。此外,为了分析烧蚀羽流对冲量耦合特性的影响,计算了不同能量密度下的羽流透射率,计算结果表明,冲量耦合系数下降阶段对应着较低的羽流透射率,即该阶段产生了较强的的等离子体屏蔽效应。

The impulse coupling characteristics of space debris material carbon fiber were studied in the experiment.The measurement and analysis method of pulsed laser ablation spot size was designed,and the ablation spot size generated by different laser energy was measured.The impulse of carbon fiber T300 ablated by nanosecond laser was measured by a torsion pendulum.The results showed that both impulse and impulse coupling coefficient increased rapidly before the laser fluence reached 6 J/cm2.However,when the energy density was greater than 6 J/cm2,the impulse increased slowly and the impulse coupling coefficient decreased gradually due to the influence of plasma shielding effect.In addition,in order to analyze the influence of the ablation plume on the impulse coupling characteristics,the plume transmittance at different laser fluences was calculated.When the fluence was greater than 6 J/cm2,the results showed that the lower the impulse coupling coefficient was,the stronger the plasma shielding effect was.