掺杂吸收剂对激光烧蚀GAP推进性能的影响

推进技术 ›› 2018, Vol. 39 ›› Issue (11): 2615-2623.

掺杂吸收剂对激光烧蚀GAP推进性能的影响

罗乐乐¹,窦志国^1,2,周伟静¹,刘昭然¹

航天工程大学激光推进及其应用国家重点实验室，北京 101416,航天工程大学激光推进及其应用国家重点实验室，北京 101416; 航天工程大学训练部，北京 101416,航天工程大学激光推进及其应用国家重点实验室，北京 101416,航天工程大学激光推进及其应用国家重点实验室，北京 101416

发布日期:2021-08-15
作者简介:罗乐乐，男，硕士生，研究领域为激光航天应用技术，微冲量测量技术。E-mail: luolele010@163.com 通讯作者:窦志国，男，硕士，教授，研究领域为先进技术及理论物理。
基金资助:
国家自然科学基金(11602304)。

Effects of Different Dopants on Laser Ablation Propulsion Performance of GAP

State Key Laboratory of Laser Propulsion and Application，Space Engineering University，Beijing 101416，China,State Key Laboratory of Laser Propulsion and Application，Space Engineering University，Beijing 101416，China;Training Department，Space Engineering University，Beijing 101416，China,State Key Laboratory of Laser Propulsion and Application，Space Engineering University，Beijing 101416，China and State Key Laboratory of Laser Propulsion and Application，Space Engineering University，Beijing 101416，China

Published:2021-08-15

摘要/Abstract

摘要： 对激光烧蚀微推力器而言，聚合物靶材的激光烧蚀推进性能至关重要。为了研究掺杂剂对靶材推进性能的影响，寻找优化靶材性能的方法，以含能聚合物聚叠氮缩水甘油醚(GAP)作为烧蚀靶材，以纳米碳粉和红外染料作为掺杂剂，采用高精度扭摆、能量计和高倍显微镜测量的方法，以冲量耦合系数、比冲和能量转化效率参数作为量化指标，改变聚合物的掺杂浓度、靶材厚度以及激光入射方式，对掺杂不同吸收剂后的GAP的推进性能进行了研究。结果表明:纳米碳粉以局部热区的形式加速聚合物的气化分解，推进性能受掺杂浓度的影响较小；掺杂纳米碳粉的GAP表现为面吸收特性，随着靶材厚度增加，喷射产物的气化程度降低，聚合物推进性能下降；较薄的掺杂纳米碳粉的GAP的等离子体阈值低，表现出高比冲和高能量转化效率，其中能量转化效率最优值接近300%，适合作为透射式激光烧蚀微推力器的烧蚀靶材。红外染料对1064nm波长的激光具有较好的吸收性能，掺杂红外染料使GAP对激光能量的吸收增强，化学能释放更充分；聚合物的推进性能对红外染料的掺杂浓度十分敏感，在掺杂浓度为5%时性能表现优秀；不同浓度红外染料掺杂下GAP的烧蚀深度不同，当靶材的厚度与烧蚀深度相近时，GAP的推进性能表现最好。

关键词: 激光烧蚀微推力器；纳米碳粉；红外染料；GAP；推进性能；真空

Abstract: For laser ablation micro-thruster， the laser ablation propulsion performance of polymer target is of great importance. To explore the way to optimize polymer propulsion performance， the energetic polymer glycidyl azide polymer(GAP) was put as ablation target， doped with nano carbon powder and infrared dye， measured by high-precision torsion balance， energy meter and high-power microscope. Considering impulse coupling coefficient， specific impulse and ablation efficiency as quantitative indices， the effects of different dopants on the propulsion performance were studied by changing dopants concentration， material thickness and laser incident mode. The results show that nano carbon powders accelerate the gasification and decomposition of polymer in the form local hotspots， and the concentrations of carbon have little effect on the propulsion performance. The surface absorption characteristic of GAP after doped with nano carbon powders results in the decrease of gasification degree of plume and propulsion performance with the increase of thickness of GAP target. The thinner GAP target doped with nano carbon powders has lower plasma threshold， meanwhile， it has higher specific impulse and high ablation efficiency which is up to 300%. The infrared dye which has good absorption to the 1064nm wavelength laser promotes release of chemical energy by increasing the polymer absorptivity of laser and concentrations of IR-dye have a great effect on the propulsion performance. 5% concentrations IR-dye doping is appropriate. The IR-dye concentrations are crucial to absorption depth of GAP. When the thickness of target is close to absorption depth，the GAP has best propulsion performance. In conclusion，the thinner GAP doped with carbon powders is more suitable for laser ablation micro-thruster in transmission mode.

Key words: Laser ablation micro-thruster；Nano carbon powder；Infrared dye；GAP；Propulsion performance；Vacuum

罗乐乐,窦志国,周伟静,刘昭然. 掺杂吸收剂对激光烧蚀GAP推进性能的影响[J]. 推进技术, 2018, 39(11): 2615-2623.

LUO Le-le¹,DOU Zhi-guo^1,2,ZHOU Wei-jing¹,LIU Zhao-ran¹. Effects of Different Dopants on Laser Ablation Propulsion Performance of GAP[J]. Journal of Propulsion Technology, 2018, 39(11): 2615-2623.

参考文献

[1] 洪延姬, 王广宇, 窦志国. 激光烧蚀微推力器研究进展[J]. 航空学报, 2009, 30(9): 1555-1565.
[2] Phipps C R, Birkan M, Bohn W, et al. Review: Laser-Ablation Propulsion[J]. Journal of Propulsion and Power, 2010, 26(4): 609-637.
[3] 叶继飞, 洪延姬, 王广宇. 激光微推进的靶特性研究进展[J]. 推进技术, 2009, 30(6): 751-756. (YE Ji-fei, HONG Yan-ji, WANG Guang-yu. Progress in Laser Micro Ablation of Target Research[J]. Journal of Propulsion Technology, 2009, 30(6): 751-756.)
[4] 刘克非. 真空环境下激光烧蚀羽流特性实验研究[D]. 北京:装备学院, 2015.
[5] Lippert T, Urech L, Fardel R, et al. Materials for Laser Propulsion: Liquid Polymers[C]. New Mexico: High-Power Laser Ablation VII, 2008.
[6] 李南雷, 叶继飞, 周伟静. 掺杂对甘油激光烧蚀冲量耦合特性的影响[J]. 推进技术, 2015, 36(10): 1595-1600. (LI Nan-lei, YE Ji-fei, ZHOU Wei-jing. Effects of Dopant on Impulse Coupling of Laser Ablated Glycerin[J]. Journal of Propulsion Technology, 2015, 36(10): 1595-1600.)
[7] Lippert T, Phipps C R. Designed Polymers for Laser-Based Microthrusters: Correlation of Thrust with Material, Plasma, and Shockwave Properties[C]. New Mexico: High-Power Laser Ablation V, 2004.
[8] Urech L, Lippert T, Phipps C R, et al. Polymers as Fuel for Laser Plasma Thrusters: A Correlation of Thrust with Material and Plasma Properties by Mass Spectrometry[C]. New Mexico: High-Power Laser Ablation VI , 2006.
[9] Urech L, Lippert T, Phipps C R, et al. Polymers as Fuel for Laser-Based Microthrusters: An Investigation of Thrust, Material, Plasma and Shockwave Properties[J].Applied Surface Science, 2007, 253(19): 7646-7650.
[10] 刘昭然, 洪延姬, 叶继飞, 等. 靶材厚度对透射式激光烧蚀性能的影响[J]. 推进技术, 2017, 38(7):1669-1674. (LIU Zhao-ran, HONG Yan-ji, YE Ji-fei, et al. Effects of Propellant Thickness on Laser Ablation Performance in Transmission Mode[J]. Journal of Propulsion Technology, 2017, 38(7): 1669-1674.)
[11] Tan R, Lin J, Hughes J, et al. Experimental Study of Coupling Coefficients for Propulsion on TEA CO₂ Laser[C]. Sendai:Proceedings of the Second International Symposium on Beamed Energy Propulsion, 2004.
[12] 李龙, 胡晓军, 唐志平. 激光化学微推进推力性能的实验研究[J]. 兵工学报, 2014, 35(6): 908-914.
[13] Phipps C R, Luke J R, Helgeson W, et al. Performance Test Results for the Laser-Powered Microthruster[J]. Performance Test Results for the Laser Powered Microthruster, 2006, 830(1): 224-234.
[14] 罗乐乐, 窦志国, 李南雷. 基于扭摆测量系统的微冲量测量方法[J]. 机电产品开发与创新, 2017, 30(2):70-73.
[15] 孙承纬, 陆启生, 范正修, 等. 激光辐照效应[M]. 北京:国防工业出版社, 2002.
[16] Sinko J E, Pakhomov A V, Millen S, et al. Delrin for Propulsion with CO₂ Laser: Carbon Doping Effects[C]. New York: Fifth International Symposium on Beam Energy Propulsion, 2008.
[17] Phipps C R, Turner T P, Harrison R F, et al. Impulse Coupling to Targets in Vacuum by KrF, HF, and CO₂, Single-Pulse Lasers[J]. Journal of Applied Physics, 1988, 64(3): 1083-1096.
[18] Phipps C R, Harrison R F, Shimada T, et al. Enhanced Vacuum Laser-Impulse Coupling by Volume Absorption at Infrared Wavelengths[J]. Laser & Particle Beams, 1990, 8(1-2): 281-298.　　　　　　　　　　　　　　收稿日期:2017-10-21；修订日期:2017-12-20。基金项目:国家自然科学基金(11602304)。作者简介:罗乐乐,男,硕士生,研究领域为激光航天应用技术,微冲量测量技术。E-mail: luolele010@163.com通讯作者:窦志国,男,硕士,教授,研究领域为先进技术及理论物理。E-mail: dou-zhiguo@tom.com(编辑:朱立影)