惰气熔融-热导法测定碳化钽粉中氮

Determination of nitrogen in tantalum carbide powder by inert gas fusion-thermal conductivity method

对惰气熔融-热导法测定碳化钽粉中氮量的分析方法进行了研究。针对碳化钽粉难熔的特点,对石墨坩埚类型、镍助熔剂、石墨粉用量和样品量等测试条件进行了优选。确定的最佳分析方法为,称取0.10～0.12g样品于0.35g镍囊中,投入装有0.03g石墨粉的高温型石墨坩埚中进行测定,分析功率为5.2kW。用钢标样确定氮工作曲线的校正系数,氮的加标回收率在94%～108%之间。采用本方法测定了2个碳化钽粉中氮量,测定值与GB/T15076.13-1994(蒸馏分离-奈斯勒试剂分光光度法)吻合,相对标准偏差(n=8)≤3.0%。

A study was conducted on the analysis of nitrogen in tantalum carbide powder by inert gas fusion-thermal conductivity method.Targeting at the refractory tantalum carbide powder,graphite crucible type,nickel flux,the amount of graphite powder and sample volume were optimized and selected.And the optimal analysis method was by weighing 0.10-0.12 g of sample and putting into 0.35 g of nickel sac.Then,the sample was put into a high temperature graphite crucible loaded with 0.03 g of graphite powder.The analytical power was 5.2 kW.The correction coefficient of nitrogen working curve was determined by steel standard sample.The standard recovery of nitrogen was 94 %-108 %.The method was adopted to determine the nitrogen content of two tantalum carbide powder.The result was consistent with GB / T 15076.13-1994（distillation separation-Nessler reagent spectrophotometry）.The RSD（n=8）≤3.0 %.