Fabrication of TiO2 nanostructured coating on Ti-6Al-4V alloy by anodizing method an‎d investigation of its characteristics

9/27/2026 12:00:00 AM

Electrochemical anodization is a conventional method for the surface modification of various metals, including titanium an‎d its alloys, whose advantages over other techniques include scalability, cost-effectiveness, an‎d the ability to incorporate desired compounds into the structure. This process results in the formation of a nanostructured coating, enhancing the materialʹs surface properties for various applications, particularly in the biomedical field. In this research, three variables anodization time, applied voltage, an‎d fluoride ion concentration were selec‎ted for investigation, with each eva‎luated at low an‎d high levels (90 an‎d 270 minutes, 20 an‎d 30 V, an‎d 0.5 an‎d 1 wt% of ammonium fluoride, respectively). Following anodization, analysis of SEM images revealed three different morphologies in the samples: the first group with a barrier oxide structure; the second with a bulk oxide coating; an‎d the final group with open-pored structures. For the porous samples, where the average pore diameter is a key parameter for the application of titanium dioxide nanostructures, the minimum an‎d maximum observed average diameters were 21 an‎d 79 nm, respectively. Furthermore, crystallographic analysis of the created coatings, compared to the uncoated sample, confirmed the formation of anatase an‎d nordstran‎dite phases. One of the outcomes of this coating is the alteration of the substrate metalʹs corrosion resistance an‎d its corresponding corrosion rate in a Simulated Body Fluid. Under some coating conditions, these properties were improved, while in others, a decrease in corrosion resistance relative to the substrate was observed an outcome that was predictable given the competition between the rate of oxide layer formation an‎d its chemical dissolution under each condition. The lowest observed value for corrosion current density (Icorr) was 0.35 µA an‎d the highest was 7.4 mA. The corrosion rate of the optimal sample is in the range of 10-3 mm/year, an‎d the corrosion rate of the uncoated substrate is in the range of 10-1 mm/year. The corrosion potential (Ecorr) values for the samples ranged from -1.17 V to 0.05 V; these values indicate the tendency of the oxide layer to corrode, with an increase in potential signifying greater layer stability.

آندايزينگ- آلياژ V4-Al6-Ti- نانوساختار- مقاومت به خوردگي- محلول شبيه سازي ‌شده بدن.

Anodizing, Ti-6Al-4V Alloy, Nanostructure, Corrosion Resistance, Simulated Body Fluid.

Fateme nazari

Dr. Hossien Aghajani- Dr. Seyed Hossien Seyedein