火花源原子发射光谱法测定线材中9种元素

Determination of Nine Elements in Wire by Spark Source Atomic Emission Spectroscopy

建立了火花源原子发射光谱法测定直径为8~12mm的小规格线材中的碳、硅、锰、磷、硫、镍、铬、铜和钒等9种元素含量的方法。试样经切割和打磨后,按规格及钢种选择对应的自制夹具固定,垂直于磨样机打磨试样的端面。用随V型板专用的定位夹具将样品定位在火花源原子发射光谱仪激发孔中心位置,使试样支架中心和电极中心对齐。盖好顶盖,用氩气吹扫火花室5s,采用能量为0.2J、频率为100Hz激发光激发样品。在优化的仪器工作条件下,试样中9种元素可在10min内完成测定。采用块状光谱国家标准样品制作校准曲线,用校正公式消除了共存元素的干扰及由标准试样和实际试样形状差异带来的系统偏差。结果显示:9种元素的质量分数均在一定范围内与其对应的响应值呈线性关系,检出限(3s)为1.5~18.1μg·g^(-1);用此方法分析实际样品,所得测定值与参考文献使用的其他方法的基本一致,测定值的相对标准偏差(n=11)均在5%以内。

A method was developed for the determination of 9 elements(including carbon,silicon,manganese,phosphorus,sulfur,nickel,chromium,copper,and vanadium)in small size wire with the diameter of8-12 mm by spark source atomic emission spectroscopy.After cutting and polishing,the sample was fixed by the self-made fixture according to the specification and steel type,to grind the end face of the sample perpendicular to the sample grinding machine.The sample was positioned at the center of the excitation hole of the spark source of atomic emission spectrometer with a special fixture attached to the v-shaped plate to keep the center of the sample support aligned with the center of the electrode.The sample was excited by 0.2 Jexcitation laser at 100 Hz after the spark chamber was swept with argon gas for 5 s.Under the optimum working conditions of the instrument,the determination of 9 elements in the sample could be completed within 10 min.The calibration curves were made by using the national standard sample of block spectrum,and the interference of coexisting elements and the systematic deviation caused by the shape difference between standard sample and actual sample were eliminated by using the calibration formula.The results showed that linearity relationships between mass fractions of 9 elements and their corresponding response values were kept in the definite ranges,with detection limits(3 s)in the range of 1.5-18.1μg·g^(-1).The proposed method was used for determination of the actual samples,determined values obtained were in conformity to those of other methods from reference,and RSDs(n=11)of the determined values were all less than 5%.