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<div>The work deals with the study of progressive materials based on a matrix of NiAl and a reinforcing FeSi phase. The fabrication is realized through vacuum induction melting and centrifugal casting. In terms of the ratio of the base matrix and the strengthening phase, two experimental alloys were prepared, which were subsequently heat treated at 1173 K/3h. The microstructural characteristics were evaluated using the LOM and SEM methods. The chemical composition of the prepared alloys was determined using EDX. The phase composition was investigated by powder X-ray diffraction analysis. The microstructure of the as-cast FeSi–NiAl (1:1) material consisted of Ni–Al-based dendrites and eutectic. The interdendritic spaces were mainly formed by Fe and Si. As a result of the heat treatment, the dendrites softened and therefore their volume fraction decreased. The microstructure of the FeSi – NiAl (2:1) alloy consisted of dendrites and eutectic. Dendrites contained Fe and Si. Ni and Al were also found in the interdendritic space. All the prepared materials had the character of in-situ composites, which means that the process of their formation occurred during the preparation process. In all samples, the matrix (binder phase) was based on Ni–Al, while the reinforcement was based on Fe–Si. Heat treatment of the samples led to the equalization of the chemical composition and the almost complete disappearance of the AlNi2Si and Al2FeSi phases. From the point of view of phase composition, all samples after heat treatment were mostly two-phase and contained phases based on FeSi and NiAl.</div>
Keywords: Composite, silicide, aluminide, melting, microstructure© This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.