为了提高激光诱导击穿光谱的质量, 探索便捷的等离子体辐射增强方法, 采用自体空间约束的方法, 研究了铜合金自体小孔约束对激光诱导等离子体辐射的增强作用。 在常压空气中, 利用Nd∶YAG脉冲激光器作为激发源, 诱导激发HPb59-1铅黄铜合金样品, 由光栅光谱仪和ICCD采集光谱, 分析了Cu和Pb元素的等离子体辐射强度随自体小孔尺寸的变化情况, 得到自体小孔约束的最佳尺寸为直径3.0 mm、 深度1.5 mm。 与无约束时相比, Cu和Pb的谱线强度分别提高了38.3%和35.4%, 信背比提高了200.2%和137.5%。 研究结果表明, 自体小孔约束方法能够有效改善激光诱导击穿铅黄铜合金样品的谱线质量, 避免外加约束结构的内壁污染对实验结果的干扰, 方法简单易行。

In this paper, self-hole confinement method was used to improve the quality of laser-induced breakdown spectroscopy and explore a convenient method to enhance the plasma radiation intensity. The effect of the self-hole confinement on plasma radiation intensity was investigated. Laser induced breakdown spectroscopy with Nd∶YAG laser was used to generate the plasma of HPb59-1 lead copper alloy sample in air. Grating spectrometer and ICCD were used to record plasma spectrum. The plasma radiation intensity of element Cu and Pb with holes of different diameters and depths were measured. Overall, the best signal intensity can be obtained with a confinement self-hole with 3 mm diameter and 1.5 mm depth. The spectral line intensities of elements Cu and Pb with self-hole are increased around 38.3% and 35.4% compared with the case without hole confinement; spectral signal-to-background ratio increased about 200.2% and 137.5%, respectively. The study results showed that the spectral quality of laser-induced lead copper alloy sample can be improved effectively by using the method of self-hole confinement. The method is sample and easy to operate which avoids the interference from the internal surface pollution of additional confinement setup of the experiment results.