熔融制样-X射线荧光光谱法测定硬质合金中钨钴镍铁铌钽铬

采用高纯氧化物经四硼酸锂和碳酸锂熔融制样制备单一氧化物熔融细粉,称取不同质量单一熔融细粉混合后二次熔融合成各元素含量不同的硬质合金人工标准样品,制作校准曲线,选用经验系数法进行基体校正,建立了无定值标样下X射线荧光光谱法(XRF)测定钨钴或钨镍类钨基硬质合金中钴、镍、铁、铌、钽、铬、钨元素的分析方法。各元素校准曲线线性范围宽,相关系数均大于0.998。对人工配制标准样品的精密度进行考察,结果的相对标准偏差(RSD)小于0.5%;对硬质合金样品进行精密度考察,精密度良好。准确度验证结果表明,测定结果与GB/T 26050-2010的测试结果及化学法测定值吻合。方法的建立解决了硬质合金定值标准样品难于获得的问题。

Determination of tungsten,cobalt, nickel,iron, niobium,tantalum and chromium in hard alloy by X-ray fluorescence spectrometry with fusion sample preparation

The single oxide fusion fine powders were prepared with high-purity oxides using lithium tetraborate and lithium carbonate as flux. The fine powders with different masses were mixed and fused to synthesize the artificial standard samples of hard alloy with different elemental contents. The calibration curves were prepared. The matrix effect was corrected with empirical coefficient method. The analysis method of cobalt, nickel, iron, niobium, tantalum, chromium and tungsten in tungsten-cobalt or tungsten-nickel tungsten-based hard alloys by X-ray fluorescence spectrometry (XRF) without certified standard samples was established. The linear range of calibration curve of elements was wide. The correlation coefficients were all higher than 0.998. The precision test was conducted on the artificially prepared standard samples with the relative standard deviation (RSD) of less than 0.5%. The determination precision of hard alloy samples was investigated and the results were good. The accuracy test indicated that the determination results were consistent with those obtained by GB/T 26050-2010 and chemical method. The proposed method solved the problems of lack of certified reference materials of hard alloy.