Determination of nitrogen in ferrosilicon by pulse melting thermal conductivity method
脉冲熔融-热导法测定硅铁中氮

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.