激光诱导击穿光谱法分析表面氧化钢铁样品中的碳硅锰磷硫铬镍铜铝

摘要

Nine elements including carbon, silicon, manganese, phosphorus, sulphur, chromium, nickel, copper and aluminum were quantitatively analyzed in middle-low alloy steel by laser-induced breakdown spectroscopy. By taking iron as the internal standard and applying signal integration averaging method, the effect of experiment parameters on laser spectroscopy signals, such as the height of sample stage, laser focus position, delay time and gas environment, were studied. Through repeated experiments, 4 mm below the sample surface was selected as the optimal focusing distance, and 4 000 Pa was selected as the optimal argon environment. Under optimal conditions, the linear correlation coefficients of nine elements in steel standard samples GSBH40068-93 are all above 0. 99. This method was applied to the direct determination of middle-low alloy steel samples with rust surface without sample pre-treatment. The result was consistent with the spark spectrum measurements.%利用激光诱导击穿光谱法对中低合金钢中的碳、硅、锰、磷、硫、铬、镍、铜、铝九种元素进行了定量分析.采用铁基体作参比、信号积分平均的数据处理方法,考察了样品台高度、激光聚焦位置、积分延迟时间、低压充氩等因素对激光光谱信号的影响.通过反复试验,确定了焦点位于样品表面之下4 mm、氩气氛围为4 000 Pa等最佳分析条件.在优化条件下,中低合金钢标准样品GSBH40068-93中9种元素线性相关系数均大于0.99.所建立的方法可应用于存在表面氧化钢铁样品的直接测定.实验表明,本法在不进行样品处理条件下测定值与火花光谱测量结果相吻合.