Spectral interference and correction of vanadium,titanium and chromium during the determination of niobium in high temperature alloy and heat-resistance stainless steel by inductively coupled plasma atomic emission spectrometry

In common methods,the standard solution of suspicious interference elements was usually added into sample solution to investigate the interference elements and interference level.In this study,the standard solution was prepared by reference materials containing different amounts of niobium and larger difference of matrix and composition elements.According to the linearity of calibration curves of analytical lines,which were obtained during the determination of niobium using standard solution prepared,the spectral interference level in the determination of niobium was investigated.The results showed that,vanadium,titanium and chromium in standard solution had interference to different analytical lines of niobium.The interference of vanadium and titanium to Nb309.418 nm and Nb313.079 nm was most serious,greatly influencing on the accuracy of determination results.After correction of spectral interference by interference coefficient method,the linearity of calibration curves of analytical lines was significantly improved.Thus,the accuracy of determination results was enhanced.After modifying the spectral interference of titanium to Nb313.079 nm,the measured content of niobium in GH4169 steel was 5.21%±0.060%,which was consistent with the certified value 5.22%.By analysis and study of linearity of calibration curves of analytical lines after correction,the reason of lower determination results of niobium in Cr18Ni20Mo2Cu2Nb stainless steel was found.