Abstract:The paper establishes a method for the determination of iron content in silicon nitride by inductively coupled plasma atomic emission spectrometry (ICP-AES) after fusion with lithium tetraborate-lithium metaborate. Lithium tetraborate-lithium metaborate is used to dissolve the sample, and the effects of the sample weighing amount and the dosage of the lithium tetraborate-lithium metaborate mixed solvent on the determination results of iron are investigated. The results show that there is a good linear relationship between the mass concentration of the iron standard solution and the spectral intensity, and the correlation coefficient is greater than 0.999. Drawing the calibration curve by the matrix matching method can eliminate the influence of the matrix effect, and the detection limit of iron is 0.0085mg/L. Taking the standard silicon nitride sample JCRM R005 as an example, the relative standard deviation (RSD) of the determination results is 3.12% (n=6), and the measured value is basically consistent with the standard value. The standard deviation of the Fe element determination in the three actual silicon nitride samples was between 2.80% and 3.70%. When this method is used to determine the standard silicon nitride samples, the determination results are within the allowable range of the standard values. The method has the advantages of rapidity, accuracy, high sensitivity, etc., and is suitable for the detection of iron element content in silicon nitride.