Spectrochemical analysis of aluminium alloys by oxide arc technique

The total combustion oxide arc technique aims at the elimination of structural effects and line intensity variations due to compositional changes in the analysis of different types of aluminium alloys. The method is based on the conversion of the synthetic solution standards of different types of aluminium alloys containing Cu, Si, Zn, Fe, Mn, Ti, Ni and Cr and unknown samples into powdered oxide. The results obtained in the analysis of aluminium alloys of varied composition and different metallurgical history using only one set of standards are fairly satisfactory in precision and accuracy. At lower concentration, standard deviation varies from 10 to 12 percent and accuracy from 8 to 10 percent of the amount present. At higher concentrations lower values are obtained both for precision and accuracy. (M.K Gupta, Senior Scientific Assistant and B.C. Kar, Assistant Director, National Metallurgical Laboratory, Jamshedpur)