Abstract:The ARL3460 spark discharge atomic emission spectrometer was used to determine the iron content in pure aluminum. As the detection time increased, the determination results of iron gradually decreased. The characteristic parameters of stability of analytical instrument were evaluated by mathematical statistics, which could not meet the stability requirements. Based on the detection principle of spark discharge atomic emission spectrometer, the cause of this malfunction was analyzed. It may be attributed to the excitation system, optical system, and photometric system. The instrument was maintained from the hardware aspect, including the maintenance of counter electrode, argon system and auxiliary electrode, the cleaning of lens, the tracing of slit, and the replacement of pipeline and photomultiplier. The stability test was conducted again after maintenance and repairment. The results showed that the stability could meet the requirements, and the stability time was improved from 0.5 h to 4 h. The hardware treatment method was more effective than the commonly used drift correction by analysis software. This method could enable the instrument to meet quality control requirements for a long time, and also provide reference for other laboratories using the same type of instrument.