基于腔体约束激光诱导击穿铝土矿光谱的参数优化

Parameter optimization of laser-induced breakdown bauxite spectra based on cavity confinement

基于外加腔体约束方法,对铝土矿中Al、Si两种元素的激光诱导击穿光谱(LIBS)实验参数进行了优化研究。通过设置压强、激光能量、延迟时间等参数,使用传统LIBS和外加腔体约束LIBS(CC-LIBS)分别对铝土矿样品进行激光烧蚀,选择SiⅠ288.15 nm和AlⅠ308.21 nm作为特征谱线对最优实验条件进行了分析。结果表明:压强为150 MPa时,谱线强度偏差最小;能量为80 mJ时,采集到的特征谱线信噪比(SNR)最大;延迟时间为1μs时,Al、Si两种元素得到的SNR最优,从而确定了最佳实验条件。与传统的LIBS相比,CC-LIBS采集到的特征谱线强度、SNR都有所提高,为铝土矿中Al、Si元素的检测提供了新的实验依据与思路,具有一定的参考价值。

Based on the external cavity constraint method, the experimental parameters of laser induced breakdown spectroscopy(LIBS) of Al and Si in bauxite were optimized. By setting the pressure, laser energy,delay time and other parameters, traditional LIBS and external cavity constrained LIBS(CC-LIBS) were used to ablate bauxite samples. The optimal experimental conditions were analyzed by selecting SiⅠ288.15 nm and AlⅠ308.21 nm as the characteristic spectrum. The results show that: when the pressure is 150 MPa, the deviation of the spectral line intensity is the smallest;when the energy is 80 mJ, the collected characteristic spectral line SNR is the largest;when the delay time is 1 μs, the SNR obtained by the two elements of Al and Si is the best, the optimal experiment condition is determined. Compared with traditional LIBS, the characteristic spectral line intensity and SNR collected by CC-LIBS have been improved, which provides new experimental basis and ideas for the detection of Al and Si elements in bauxite and has certain reference value.