脉冲熔融-热导法测定硅铁中氮

硅铁中氮的测定没有标准方法和相应的参考物质，本文通过以屑状钢中低氮参考物质建立氮校准曲线，采用镍箔助熔自动分析模式测定，建立了脉冲熔融热导法测定硅铁中氮的方法。对比了直接投样手动分析模式、添加石墨粉手动分析模式和镍箔助熔自动分析模式3种分析模式对氮的测定影响，结果表明，采用镍箔助熔自动分析模式测定硅铁中氮，氮释放完全、测试结果稳定。本方法的测定下限为0000 37%，用于2种硅铁样品中氮的测定，测定结果的相对标准偏差分别为10%和9%（n=4）。

Determination of nitrogen in ferrosilicon by pulse melting thermal conductivity method

There are no standard method and corresponding reference material for the determination of nitrogen in ferrosilicon.In this study,the calibration curve of nitrogen was plotted using reference material of crumb steel with low nitrogen.The determination of nitrogen in ferrosilicon by pulse melting thermal conductivity method was established using nickel foil fluxing-automatic analysis mode.The influences of three analysis modes including direct injection-manual analysis,graphite powder addition-manual analysis and nickel foil fluxing-automatic analysis on the determination were compared.The results showed that when nickel foil fluxingk-automatic analysis mode was used to determine the nitrogen in ferrosilicon,the release of nitrogen was complete and the measurement results were stable.The lower determination limit of this method was 0.000 37 %.The proposed method was applied to the determination of nitrogen in two types of ferrosilicon samples,and the relative standard deviations(RSD,n=4) of measurement results were 10 % and 9 %,respectively.