OBRABOTKAMETALLOV MATERIAL SCIENCE Vol. 27 No. 3 2025 matrix, indicated by the detection of carbon, silicon, and aluminum. Furthermore, the EDX results clearly demonstrate the presence of graphene nanoparticles in the aluminum matrix, with carbon peaks observed in both specimens. The dispersion of SiC and graphene nanoparticles throughout the aluminum matrix highlights their potential to enhance the mechanical properties of the composite material. Energy dispersive X-ray spectroscopy (EDX) analyzes the elemental composition of the Al7075-based nanocomposites. Figs. 6 and 7 show a dominant aluminum signal in the EDX spectra, confirming that the matrix material is primarily aluminum. The presence of titanium (Ti) and zirconium (Zr) peaks suggests their role in mechanical optimization as reinforcing elements. Silicon (Si) may be present as intermetallic compounds or ceramics. Trace peaks of iron (Fe), manganese (Mn), chromium (Cr), nickel (Ni), copper (Cu), and zinc (Zn) indicate the presence of a multi-elemental alloying system designed to improve strength, wear resistance, and corrosion resistance. While EDX has limited sensitivity to light elements like carbon, a minor carbon peak near 2 keV suggests the presence of graphene or graphitic carbon structures. Even at low concentrations, graphene’s high tensile strength and large surface area contribute to enhanced structural and functional performance of the composite. Overall, the EDX results demonstrate the successful incorporation of both micro- and nano-scale reinforcements into the aluminum matrix, highlighting its suitability for advanced structural applications. Fig. 7 illustrates the elemental distribution within the eighth composite specimen. The prominent AlKα signal at 1.5 keV confirms aluminum as the primary matrix material. The presence of a strong MgKα peak indicates the addition of magnesium to enhance the strength-to-weight ratio and improve corrosion resistance. Peaks corresponding to titanium (TiLα, TiKα), zirconium (ZrLα), and silicon (SiKα) suggest the presence of reinforcing phases that contribute to mechanical and thermal stability. Transition metals such as chromium (Cr), manganese (Mn), iron (Fe), nickel (Ni), copper (Cu), and zinc (Zn) are detected across a wide energy range, particularly between 5 and 9 keV, suggesting their role as alloying elements or secondary reinforcements. These constituents can enhance the composite’s hardness, wear resistance, and multifunctionality. Variations in magnesium content between spectra suggest a compositional design modification. Overall, the spectrum depicts a complex multi-phase aluminum-based composite system with tailored elemental additions for improved structural and functional performance. Fig. 8 presents optical micrographs illustrating the microstructures of Specimen 7 (Al7075 + 0.5% graphene + 3% SiC) and Specimen 8 (Al7075 + 1% graphene + 2% SiC). Both specimens were fabricated with different combinations of graphene and SiC. Specimen 7 (Fig. 8, a) exhibits a consistently polished grain structure with well-defined, continuous grain boundaries. The absence of porosity or clustering suggests enhanced interfacial bonding, while the presence of fine grains indicates effective nucleation facilitated by properly dispersed SiC particles. High-resolution SEM images reveal the nanoscale reinforcement particle size and dispersion within the composite matrix. The presence of fine particles ranging from 62.57 to 91.54 nm indicates a well- a b Fig. 8. Microstructure observed for (a) Specimen 7, (b) Specimen 8
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