OBRABOTKAMETALLOV MATERIAL SCIENCE Vol. 26 No. 3 2024 с Fig. 7. The End The microdiffraction patterns obtained from different areas are represented, first of all, by reflections of varying intensities. The identified reflections correspond to the BCC phase Al – 91 wt. %, Si – 8 wt. % (PDF Card – 04-003-7125). In the microdiffraction pattern, Figure 8 b, obtained using the largest field diaphragm at the low magnification of the specimen, there are also reflections located circumferentially which indicates that there are fine particles in the structure of the specimen. At high magnifications and dark-field images it is clearly visible that these fine particles are located at the grain boundaries. To analyze the homogeneity of element distribution in the specimen under study energy-dispersive microanalysis was used. First of all, element distribution maps throughout the analysis area were built. Mapping showed that the main element of the alloy, Al, is distributed evenly in the grains, but its content decreases along the grain boundaries. The second most abundant element, Si, on the contrary, is mainly concentrated along the grain boundaries. The third element in terms of content, Mg, is distributed evenly throughout the volume under study. Based on the nature of the total spectrum, Figure 9, no other elements are detected in the specimens. The elemental composition of the area under study is presented in Table 2. To confirm the local heterogeneity of the element composition we also completed the study of elemental composition along a given line. The results of the study are shown in Figure 10. The nature of elements distribution is similar to that of the mapping: at the grain boundaries we observe reduced Al and increased Si content. As can be seen the concentration of Mg, when studied using this method, is also heterogeneous. However, since the Mg content in the composition is low (less than 0.5 wt. % according the data of elemental analysis) this cannot be postulated accurately. A specimen of a complex geometric shape (Figure 11) was produced from the prepared powder mixture under the obtained optimal SLM conditions.
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