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

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 of 8-12 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 J excitation 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 (3s) 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%.