Characterization of the amorphous metallic alloy Al85Ni10Sm5

Abstract

Aluminum alloys are highly significant materials in the industry due to their excellent mechanical properties and corrosion resistance. These alloys are widely used in various applications in the automotive and aerospace industries. The addition of alloying elements such as nickel, copper, and magnesium allows for different combinations of properties, which makes the alloys more versatile. Among aluminum alloys, the amorphous alloys studied in this work have received increasing attention due to their unique properties. Additionally, there is a limited amount of research on these materials, unlike the numerous studies already conducted on conventional crystalline structure alloys. In this work, the metallic alloy with the atomic composition Al85Ni10Sm5 and an amorphous structure, produced by melt-spinning, was structurally, thermally, and electrochemically characterized. The structural and thermal characterization was performed using X-ray diffraction (XRD), scanning electron microscopy (SEM), and differential scanning calorimetry (DSC) techniques to confirm its amorphous nature. The electrochemical characterization was carried out through open circuit and potentiodynamic polarization tests in an aqueous medium with 3.5% mass NaCl at room temperature. The results indicate that the fully amorphous alloy is of the glassy type, with Tg = 522 K, and exhibits low thermal stability (∆Tx = 16 K). The electrochemical tests show a corrosion potential of approximately -520 mV relative to the saturated calomel reference electrode, suggesting that the amorphous alloy is more corrosion-resistant than pure aluminum in its crystalline state.

Keywords

• Amorphous Al-Ni-Sm Alloy
• Physical characterization
• Electrochemical characterization