离心浇铸制样-X-射线荧光光谱法测定铌铁合金中铌硅磷

Determination of niobium,silicon and phosphorus in ferrocolumbium by X-ray fluorescence spectrometry using sample preparation technique of centrifugal casting

采用纯铁作为铌铁合金的稀释剂,经高频加热熔融,离心浇铸成块状样品,用X-射线荧光光谱法分析铌铁合金中铌、硅、磷。为了避免陶瓷坩锅材料污染测定组分,采用内层涂有氧化锆的陶瓷坩锅,该制样方法能有效克服铁合金存在的矿物效应和颗粒效应。试验结果表明,块状样品表面不同部位及不同深度的化学成分分布均匀,相同熔融条件下的样品重复性良好,解决了用粉末压片制样对测定结果带来的误差。方法用于测定铌铁合金中Nb,Si,P,其相对标准偏差分别为0.14%,1.97%,3.03%,与化学法测定结果有较好的一致性,满足了常规分析要求。

Through using pure iron as the diluting agent, the sample of ferrocolumbium was prepared by high frequency melting and centrifugal casting into massive sample. Then niobium, silicon and phosphorus in ferrocolumbium were determined by X-ray fluorescence spectrometry. In order to prevent ceramic crucible material from polluting testing component, the ceramic crucible with zirconia coating inside was used. This sample preparation technique could effectively eliminate mineral effect and particle effect of ferroalloy. The results indicated that the chemical compositions in sample surface and different depths were homogenous and the repeatability of determination results was also good under the same preparation conditions, which eliminate the error caused by sample prepared by powder press. This method has been applied to the determination of niobium, silicon and phosphorus in ferrocolumbium with the RSDs of 0.14 %, 1.97% and 3.03%, respectively. The determination results were in good agreement with those obtained by chemical method. This method has fulfiled the requirements of routine analysis.