用激光点火辅助火花诱导击穿光谱技术实现铝合金的高灵敏元素分析

报道了采用激光点火辅助火花诱导击穿光谱技术分析铝合金中痕量元素时的分析行为。用低能量激光脉冲聚焦于样品表面并在放电电极之间产生等离子体来触发高压火花放电以改善火花诱导击穿光谱技术的分析行为。在当前空间几何配置下，研究得到了最佳的放电电压和储能电容等参数并在最佳实验条件下分析了样品中的铜元素，其检出限达到0.7 ppm。激光点火的辅助手段改善了火花诱导击穿光谱技术在元素分析时信号的稳定性、提高了分析精度。同时它还能够有效地降低放电电压，改善其空间分辨本领。研究表明激光点火辅助火花诱导击穿光谱技术具有灵敏度高、稳定性好以及具有较好的空间分辨本领的特点，非常适合于各种合金中的痕量元素分析。

Laser Ignition Assisted Spark-Induced Breakdown Spectroscopy for Element Analysis of Aluminum Alloy with Enhanced Sensitivity

The analytical performance of laser ignition assisted spark-induced breakdown spectroscopy (LI-SIBS) for the analysis of trace metal in aluminum alloy was reported in the present article. In order to improve the analytical performance of spark-induced breakdown spectroscopy, a low energy laser pulse was focused on the surface of the sample to produce plasma between discharge electrodes to trigger high voltage spark discharge. Under current geometrical arrangement, optimized discharge voltage and capacitance were determined, and copper in aluminum alloy was analyzed under optimized experimental condition. The limit of detection of copper in aluminum alloy was determined to be 0.7 ppm. Both signal stability and measurement accuracy for spark-induced breakdown spectroscopy were improved with the assistance of laser ignition. The discharge voltage could be reduced and the spatial resolution could be improved with the assistance of laser ignition at the same time. It was demonstrated that LI-SIBS has the characteristics of high sensitivity, good stability and better spatial resolution and is suitable for trace elements analysis in different alloys.