Investigation of Molecular Interferences at GDMS Analysis of Main Elements and Microalloing of High-Entropy Alloy AlCrFeCoNiCu

The peculiarities of the glow discharge mass-spectrometry (GDMS) analysis of the main components and elements of microalloying of high-entropy AlCrFeCoNiCu alloy are considered in the paper. Molecular interferences of Ar (x)A(y)(+i), Ar (x)G(+i), A B-x(y)+i types (where A, B are the components of the sample, G are single and 2-3 atomic gases; x, y = 1, 2, i - charge of ion, i = 1, 2), which are formed during cathode sputtering of this alloy in glow discharge plasma were calculated and experimentally tested. It is shown for spectrometers at resolution R-0.5 >= 7000, the greatest influence of molecular ions of Me-2(+) and ArMe+ types exist in the range of isotope masses from Rb-85 to about Ag-107. A careful selection of isotopes is required in this mass range to meet detection limit conditions. In other areas of the mass spectrum, the sensitivity of the analysis is limited by the background current and the sensitivity of the detectors and is at the usual ppb-level for this method.