Issue 75

Ravikumar M et alii, Frattura ed Integrità Strutturale, 75 (2026) 326-338; DOI: 10.3221/IGF-ESIS.75.23

(a) (b) Figure 9: Wornout surfaces SEM image of (a) Al 7075 alloy and (b) n-Mg modified Al 7075

Figure 10: Corrosion rate of n-Mg modified alloy.

Corrosion rate Fig. 10 displays the developed modified alloy's corrosion rate. According to experimental findings, pure aluminum had the lowest rate of corrosion and weight loss. Weight loss increased noticeably when the quantity of nano sized magnesium particulates increased. Given that magnesium behaves anodically in comparison to the aluminum alloy, this is explained by its strong reactivity. According to [9], the durability of the protective oxide layer is often affected by magnesium's increased reactivity, which speeds up corrosion at greater Mg concentrations. The corrosion properties of the Al7075 alloy as well as the nano sized magnesium modified Al7075 alloy following 30 days of submersion in saltwater is depicted in the SEM study in Fig. 11. Localized corrosion is indicated by the corroded samples' uneven, concave convex surface characteristics. The existence of internal tensions or dehydration of hydroxides, which may be linked to stress corrosion cracking caused by magnesium, is indicated by the emergence of cracks and pits inside the corrosion products. The alloy surface first develops a protective Al 2 O ₃ layer that provides significant corrosion resistance. Significant localized corrosion, however, starts to form beneath the surface after extended exposure. The development of nano pores that weaken the protective layer's integrity is thought to be the cause of this degradation. Long-term

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