论文部分内容阅读
用波长1.06μm,脉冲半峰全宽(FWHM)约10 ns的Nd∶YAG激光照射在薄铜靶上,研究了打孔效率同离焦量之间的关系。实验中脉冲能量分别为26 mJ,52 mJ,85 mJ,204 mJ和274 mJ,在各脉冲能量下,改变离焦量,测出相应的打孔效率。结果表明,离焦量是影响打孔效率的重要因素;实际打孔过程中,采用较低的激光功率密度和+3~+4 mm的离焦量是合理的选择。当离焦量d<0时,打孔效率主要由激光照射产生的热烧蚀、等离子体屏蔽两个物理机制决定;当离焦量d>0时,打孔效率是激光照射产生的热烧蚀、等离子体屏蔽和焦斑处空气等离子体辐射的促吸收效应共同作用的结果。
The relationship between the efficiency of drilling and the amount of defocus was studied using a Nd: YAG laser with a wavelength of 1.06μm and a pulse width at half maximum (FWHM) of about 10 ns on a thin copper target. In the experiment, the pulse energy was 26 mJ, 52 mJ, 85 mJ, 204 mJ and 274 mJ, respectively. Under the pulse energy, the defocusing quantity was changed and the corresponding drilling efficiency was measured. The results show that the defocusing amount is an important factor affecting the drilling efficiency. In the actual drilling process, the lower laser power density and the defocus amount of +3 ~ +4 mm are reasonable choices. When the defocusing quantity d <0, the drilling efficiency is mainly determined by the thermal ablation generated by the laser irradiation and the two physical mechanisms of the plasma shielding. When the defocusing quantity d> 0, the drilling efficiency is the heat generated by laser irradiation Erosion, plasma shielding and focal spot at the air plasma radiation absorption effect of the joint effect of the results.