Determination of silicon, manganese and magnesium in cast iron by atomic emission spectrometry

A spectrograph with high voltage spark source, once pre-burned and continuous photography was used for the quantitative determination of Silicon, Manganese and Magnesium in cast iron. The experimental conditions were optimized including the control of pre-burning time, plate moving rate, slit height of the blackness measuring, the selection of electrode material, the distance between the electrodes, shape of the electrode and the diminution of interferences. The determination range of contents (omega/omega) are 0.010% - 0.090% for Mg, 1.50% - 3.50% for Si and 0.40% - 1.10% for Mn. The relative standard deviations are 10.4%, 1.9% and 3.0% for Mg,Si, and Mn, respectively.