熔融制样-X射线荧光光谱测定镍铬生铁中主次成分  

Determination of major and minor elements in nickel-chromium pig iron by X-ray fluorescence spectrometry with fusion sample preparation

作　　者：刘云利 曾垚 LIU Yunli;ZENG Yao(Liugang Zhongjin Stainless Steel Co.,Ltd.,Yulin 537624,China)

机构地区：[1]柳钢中金不锈钢有限公司,广西玉林537624

出　　处：《冶金分析》2024年第6期57-63,共7页Metallurgical Analysis

摘　　要：为解决高温熔融时镍铬生铁中还原物质对铂金坩埚的腐蚀问题,开发出一步熔融法制备镍铬生铁玻璃片的方法。称取0.1 g试样,用5.0 g四硼酸锂+2.0 g偏硼酸理+1.5 g四硼酸锂覆盖方式加入助熔剂,1.0 g碳酸锂为氧化剂;在700℃保持10 min,850℃保持10 min,用500 g/L溴化锂溶液为脱模剂,熔融得到光滑、平整、均匀的玻璃片;用国标方法定值的具有一定含量跨度且呈一定含量梯度的生产样作为校准样品系列绘制校准曲线,用铬对铁、硅分别进行重叠校正,而镍、铬、磷谱线不需基体校正,采用X射线荧光光谱法(XRF)对玻璃片进行测定,建立了镍铬生铁中总铁(TFe)、镍、铬、铁、硅含量的测定方法。按照实验方法测定5个镍铬生铁样品中的TFe、镍、铬、铁、硅,结果的相对标准偏差(RSD,n=11)为0.13%~1.3%。分别采用本法与国标方法、电感耦合等离子体原子发射光谱法(ICP-AES)进行方法比对,测定结果基本一致。方法使用全自动熔融炉将氧化和熔融步骤整合,制备玻璃片,省去繁琐复杂的挂壁操作,并有效保护铂金坩埚不受腐蚀。In order to solve the corrosion problem of platinum crucible caused by reducing substances in nickel-chromium pig iron samples during high temperature melting,a one-step melting method was developed to prepare nickel-chromium pig iron glass sheet.0.1 g of sample was weighed.The flux was added by 5.0 g of lithium tetraborate,2.0 g of lithium metaborate,and 1.5 g of lithium tetraborate covering method.1.0 g of lithium carbonate was used as oxidant.After the sample was melted at 700℃ for 10 min and 850℃ for 10 min,a smooth,flat and uniform glass sheet was obtained with 500 g/L lithium bromide solution as release agent.The production samples with a certain content span and a certain content gradient,which were determined by national standard methods,were used as calibration sample series to draw calibration curves.The overlapping corrections of iron and silicon were conducted with chromium,respectively.The matrix corrections of spectral lines of nickel,chromium and phosphorus were not required.The prepared glass sheet was determined by X-ray fluorescence spectrometry(XRF).Thus,a method for determination of total iron(TFe),nickel,phosphorus,chromium and silicon in nickel-chromium pig iron was established.The contents of TFe,nickel,phosphorus,chromium and silicon in five nickel-chromium pig iron samples were determined according to the proposed method,and the relative standard deviations(RSD,n=11)were between 0.13% and 1.3%.The proposed method was compared with national standard methods and inductively coupled plasma atomic emission spectrometry(ICP-AES).It was found that the results were basically consistent.In the proposed method,the procedures of pre-oxidation and melting were integrated by a fully automatic melting furnace for sample preparation.The complicated wall hanging operation was not required.Moreover,it could effectively protect the crucible from corrosion.

关 键 词：一步熔融 熔融制样 镍铬生铁 X射线荧光光谱法(XRF) 主次元素 助熔剂 氧化剂 

分 类 号：O657.34[理学—分析化学] TF644[理学—化学]