Effect of alkaline etching on microstructure and anticorrosion performance of anodic film on Al-Mg-Si alloy

Characterization of the Anodic Film and Corrosion Resistance of an A535 Aluminum Alloy after Intermetallics Removal by Different Etching Time

“…Apparently, the intermetallics inhibit the oxide film growth, as evidenced by the EDS element mapping of oxide film surface in Figure 5 that shows that the layer of oxide is discontinuous. This confirms the harmful role of intermetallics in the formation of a uniform oxide film and the necessity of a proper pretreatment time, as reported previously for other Al-Mg-Si alloys [35]. film being more uniform, as demonstrated in Figure 4e,f.…”

“…The nature of these voids is related to the formation of grooves in place of intermetallics on the surface as a result of alkaline etching. Longer etching produces more voids and also accelerates the growth of the anodic oxide film [35]. The results also show that the alloy etched for 4 min and sealed with nickel fluoride still has more voids left on the surface as compared to the stearic acid sealant.…”

“…The thickness of the anodic film was also measured. The results in Figure 10 show that the anodic layer thickens with increasing the alkaline etching time to 4 min due to the removal of intermetallics and increased growth rate of anodic film [35]. The average thickness increases from 40 µm up to about 70 µm, depending on the type of sealants.…”

Anodized Aluminum Surface with Topography-Mediated Antibacterial Properties

“…In a related study, previously, they demonstrated the antimicrobial activity of a topography-mediated aluminum fabricated by chemical etching against common multidrug resistant (MDR) pathogens, such as Pseudomonas aeruginosa (PA) and Staphylococcus aureus (SA), and on respiratory viruses, such as respiratory syncytial virus (RSV) and rhino virus (RV). While desirable nanoscale topography is achievable by chemical etching, mechanical properties of nanoscale features are rather weak . An alternative surface treatment process resulting in aluminum surfaces with excellent anticorrosive, tribological, and mechanical properties, such as anodization, appears promising in terms of robustness …”

Characterization of Anodized Al 1050 with Electrochemically Deposited Cu, Ni and Cu/Ni and Their Behavior in a Model Corrosive Medium

“…Particularly, the deposition of metals inside the pores of the Al 2 О 3 -matrices is successfully applied for the formation of functional coatings, having a number of practical applications. The AAO layers, modified with Cu [12][13][14][15][16][17][18][19][20], Ni [21][22][23][24][25][26][27][28][29] and combined Cu and Ni [30][31][32][33][34], are implemented as decorative and corrosion protective coatings [35][36][37][38][39][40][41][42][43][44][45], as well as solar absorbers [22,24,25].…”