Yuan Haofang, Geng You, Wang Xianyu, Wu Lizhi, Shen Ruiqi
Department of Applied Chemistry, School of Chemistry and Chemical Engineering, Nanjing University of Science and Technology, Nanjing, Jiangsu 210094, China.
Micro-Nano Energetic Devices Key Laboratory, Ministry of Industry and Information Technology, Nanjing, Jiangsu 210094, China.
ACS Appl Mater Interfaces. 2024 Jan 31;16(4):5326-5335. doi: 10.1021/acsami.3c18250. Epub 2024 Jan 19.
Laser-driven flyers (LDF), which can launch the flyer on the interaction of a laser pulse with a thin film of metal, have been widely used in many fields, such as ignition, space scrap metal science, and dynamic high-pressure physics. However, at present, further development of LDF is being hindered by the high reflectivity of the ablation layer and low energy utilization efficiency of LDF on the fiber end face. Herein, improved LDFs were designed and fabricated by mask plate and magnetron sputtering. Improved LDF incorporates a Ti/Al composite film as the ablation layer, while the flyer layer features a smaller diameter round platform design. Reflectivity of samples under static and dynamic conditions and driving characteristics of samples were tested using an optical isolator and photonic doppler velocimetry system. The velocity of the improved LDFs reaches 1.7 km/s with a peak acceleration of 8.7 × 10 m/s. LDF with a Ti/Al composite film as the ablation layer demonstrates a static absorption rate of 59%, which gradually increases to 65% under laser irradiation. This absorption rate is notably higher compared with the static absorption rate (20%) and the peak absorption rate under laser irradiation (40%) of an Al layer. Consequently, there is a substantial improvement of about 35% in the flyer velocity. In contrast to the plane-shaped LDF, the velocity profile of the flyer and impact crater morphology suggest that the step-shaped LDF offers a 15% improvement in velocity and a 50% increase in acceleration, with better flyer integrity observed.
激光驱动飞片（LDF）通过激光脉冲与金属薄膜相互作用来发射飞片，已在许多领域得到广泛应用，如点火、太空废金属科学和动态高压物理等。然而，目前LDF的进一步发展受到烧蚀层高反射率以及光纤端面上LDF能量利用效率低的阻碍。在此，通过掩膜板和磁控溅射设计并制备了改进型LDF。改进型LDF采用Ti/Al复合膜作为烧蚀层，而飞片层采用较小直径的圆形平台设计。使用光隔离器和光子多普勒测速系统测试了样品在静态和动态条件下的反射率以及样品的驱动特性。改进型LDF的速度达到1.7 km/s，峰值加速度为8.7×10 m/s。以Ti/Al复合膜作为烧蚀层的LDF静态吸收率为59%，在激光辐照下逐渐增加到65%。与Al层的静态吸收率（20%）和激光辐照下的峰值吸收率（40%）相比，该吸收率显著更高。因此，飞片速度有大约35%的显著提高。与平面形状的LDF相比，飞片的速度分布和撞击坑形态表明，阶梯形LDF的速度提高了15%，加速度增加了50%，并且观察到飞片完整性更好。
