高频燃烧红外吸收法测定氮化硅铁中碳

称取0.2g样品,置于预先盛有(0.300±0.005)g锡粒的坩埚内,覆盖(0.400±0.005)g纯铁和(2.000±0.005)g钨粒进行分析,建立了高频燃烧红外吸收法测定氮化硅铁中碳含量的分析方法。实验中,考虑到氮化硅铁标准样品较少,故选择由0.04g氮化硅标准样品JCRM R008和0.16g纯铁标准样品GBW 01148a混合配制的氮化硅铁合成校准试样(w(C)=0.025 7%)与氮化硅铁标准样品GSB 03-2469-2008(w(C)=0.35%)来绘制校准曲线。方法中碳的线性范围为0.025%~0.35%,检出限为0.000 45%。由0.10g氮化硅标准样品JCRM R008和0.10g纯铁标准样品GBW 01148a混合配制氮化硅铁合成样品1,以及由0.08g氮化硅铁标准样品GSB 03-2469-2008和0.12g氮化硅标准样品JCRM R006混合配制氮化硅铁合成样品2,采用实验方法对其中碳进行测定,测定值与认定值基本一致。采用实验方法对氮化硅铁实际样品中的碳进行测定,所得结果的相对标准偏差(RSD,n=6)为1.2%~1.7%。

Determination of carbon in ferrosilicon nitride by high frequency combustion infrared absorption method

0.2 g of sample was transferred into crucible containing(0.300± 0.005)g of tin particles. Then, (0.400±0.005)g pure iron and (2.000± 0.005)g tungsten particles were added for analysis. The determination method of carbon in ferrosilicon nitride by high frequency combustion infrared absorption was established. Since there were only few standard samples of ferrosilicon nitride in experiments, the calibration curves were prepared using standard sample (GSB 03-2469-2008,w(C)=0.35%) and synthetic sample (w(C)=0.025 7%, which was prepared using standard samples including 0.04 g of silicon nitride JCRMR 008 and 0.16 g of pure iron GBW 01148a). The linear range of carbon in proposed method was 0.025%-0.35%, and the detection limit was 0.000 45%. The synthetic sample 1 was prepared using 0.10 g of silicon nitride JCRM R008 and 0.10 g of pure iron GBW 01148a. The synthetic sample 2 was prepared using 0.08 g of ferrosilicon nitride GSB 03-2469-2008 and 0.12 g of silicon nitride JCRM R006. The content of carbon in synthetic samples was determined according to the experimental method. The found results were basically consistent with the certified values. The proposed method was applied to the determination of carbon in actual sample of ferrosilicon nitride. The relative standard deviations (RSD, n=6) were in the range of 1.2%-1.7%.