水中薄片激光打孔反常现象的分析

Abnormal Phenomenon of Laser-Drilling a Plate Underwater

1.
Department of Electronics & Information, East China Shipbuilding Institute, Zhenjiang 212003, China;
2.
Department of Applied Physics, Nanjing University of Science & Technology, Nanjing 210094, China

摘要: 在其它条件相同的情况下，水中激光在金属薄片上的打孔效率远高于空气中的打孔效率。采用自行研制的基于光偏转原理的力学传感器，分别测量了激光在空气和水中烧蚀薄片时薄片表面所受的力。实验结果表明，激光在空气中烧蚀薄片时，靶材仅受到烧蚀力的作用，而在水中打靶时，靶受到烧蚀力和两次射流冲力等综合作用，且水中的三次冲力在幅值和持续时间均远大于空气中靶材所受的冲力，并用扫描电子显微镜观察了孔的形貌，进而分析了水下激光打孔效率远高于空气中打孔效率的机制。
- 力学传感器 /
- 激光 /
- 打孔效率 /
- 烧蚀
Abstract: The efficiency of laser-drilling a metal plate in water was observed higher than that in air. A new mechanical sensor based on optical deflection technique was applied to investigate the force acting on a metal in water and air respectively during laser-matter interaction. It is shown that in air the sample is only affected by laser-induced ablation, while underwater it is impacted not only ablation, but also two liquid-jet impulses. Both the amplitude and duration of three forces underwater are much larger than those in air. By scanning electronic microscope, the shape of laser-drilling holes is observed and their different mechanisms in water and air are analyzed in detail.
- mechanical sensor /
- laser /
- drilling efficiency /
- ablation