飞秒激光在甘油介质中烧蚀恒弹合金的规律研究

A Study of Femtosecond Laser Ablation of Constant Elastic Alloy in Glycerol Solution

为了深入研究恒弹合金的飞秒激光烧蚀工艺,探索了飞秒激光在甘油介质中对恒弹性合金进行烧蚀的规律。因为激光烧蚀诱导产生的气泡在液体辅助烧蚀中扮演了一个重要角色,因此在实验中使用了粘度较大的甘油溶液,以研究气泡对于烧蚀规律的影响。在进行烧蚀时,采用不同的离焦量分别打点,以研究溶液介质对于激光聚焦点位置的影响。实验表明,在甘油溶液介质中对样品表面烧蚀时,孔深的变化比之在空气中烧蚀差别很大,在离焦量由正到负的过程中出现了两个孔深峰值,分别位于正负离焦量区间,并且在零离焦量附近达到极小值。而孔径的变化则基本呈现聚焦点位置越深入样品表面内部越大的趋势。根据对实验过程和结果的观察分析,这主要是由于气泡对激光烧蚀能力产生了很大的影响,从而导致了液体辅助烧蚀与在空气中烧蚀截然不同的结果。

In order to further study the mechanism of the femto-second laser ablation of constant elastic alloy,this paper explores the femtosecond laser ablation of constant elastic alloy in glycerol solution.Laser-induced bubbles play an important role during liquid assisted ablation.Therefore glycerol solution is chosen due to its larger viscosity which makes it easier to generate bubbles.During the ablation,multiple craters have been drilled under different defocusing distances,so as to study the influence of liquid solution to the laser focal point.The results show that,during the process from positive defocusing distance to negative defocusing distance,the depths of craters reach its peak twice,and a minimum value occurs near the zero defocusing distance,which is very distinctive from the ablation in air.The diameters of craters basically enlarge along with the reduction of defocusing distance.However,same as the depths,the diameters reach a minimum value near the zero defocusing distance.From the observation of experiments and analysis of results,such phenomenon is mainly because of the laser-induced bubbles which significantly affects the efficiency of laser ablation.