Determination of 15 Trace-Impurities in High Purity Tungsten by Inductively Coupled Plasma Mass Spectrometry

The traceimpurities in high purity tungsten were determined by inductively coupled plasma mass spectrometry (ICP-MS). The interferences for K, Ca, Fe and Si produced by polyatomic ions were eliminated by H₂ reaction technology. Under the optimized conditions of measured isotopes and internal standard elements, the acid and matrix effects were investigated， and the method for the analysis of 15 trace-impurities in high purity tungsten was established. Determination limits obtained ranged between 0.12 and 0.50 μg/g for this fifteen impurities. The accuracy of the method was evaluated by recovery measurements on spiked samples, and good recovery results (96.1%—110.6%) with precision（RSD） of less than 8% were achieved. The method was used for the analysis of high purity tungsten bar and power. The result showed that the method was suitable for the analysis of 4N—5N high purity tungsten products.