MATHEMATICAL MODELING OF MUTUALLY INFLUENCING ELEMENTS BY THE METHOD OF FUNDAMENTAL PARAMETERS FOR X-RAY FLUORESCENT ANALYSIS OF HIGH-ENTROPY AlCrFeCoNiCu ALLOY

Abstract

A mathematical model and a computer program (FLUOR81) have been developed to implement the method of fundamental parameters for X-ray fluorescence analysis of new types of alloys. The model takes into account the excitation of X-ray tube by poly-chromatic radiation and the secondary excitation of some elements by other ones. Testing the program using state standard samples of steels and alloys with nickel and cobalt matrices show that the intensity of characteristic lines can be calibrated using pure elements if there are no standard samples. In this case, the relative measurement error is no more than 3–4%. This approach is used for mathematical modeling of the mutual influence of elements in the AlCrFeCoNiCu high-entropy alloy (HEA). The relative deviations of the initial concentrations of components (ignoring their mutual influence) from the stoichiometric values were found to be within ±50% and slightly change with concentration by varying the stoichiometric coefficients in the AlCr_xFeCo_xNi_xCu alloy (x = 0.5, 1, 2). These patterns can be used for semiquantitative estimates of the composition of HEAs for which there are no standard samples. To obtain results with a relative error of 3–4%, calculations using the developed program are needed.