中文摘要：

利用1064nm波长Nd：YAG脉冲激光诱导击穿合金钢产生激光等离子体光谱，采用高分辨率及门宽控制的ICCD探测LIBS信号光谱。选用铁元素原子谱线404．581，414．387，427．176和438．355nm进行分析，研究了不同实验参数对LIBS光谱信号强度的影响结果。实验结果表明，激光脉冲能量、激光聚焦位置以及ICCD探测器的延时等实验参数对合金钢LIBS信号有较大影响。通过优化这些实验参数，获得高光谱强度和信背比的LIBS信号，确定了LIBS技术用于合金钢微量元素成分分析的最佳实验条件，从而开展合金钢样品成分分析。

英文摘要：

Laser induced plasma spectroscopy of alloy steel was produced by Nd ： YAG pulsed laser at 1 064 nm, and the spec-tral signal was detected by high resolution and width controlled ICCD. Several Fe atomic spectral lines such as 404. 581, 414. 387, 427. 176 and 438. 355 nm were chosen for analysis, and the effects of different experimental parameters on LIBS spec-tral signal intensity were investigated. It is shown that the experimental parameters such as pulse energy, laser focus location and laser delay time have great influence on the LIBS signal. LIBS signals with high spectral intensity and signal-background ra-tio （SBR） as well as the optimum experiment conditions were obtained by optimizing these experiment parameters so as to make composition analysis of the alloy steel.