The purpose of this paper is to investigate improving high‐temperature oxidation resistance of titanium by developing new coatings based on aluminum and its combination with the substrate. Nanocrystalline plasma electrolytic saturations were applied on the surface of commercially pure titanium in an aqueous bath. The aim was to obtain good corrosion and oxidation resistances of the differently treated samples by investigation of their nanostructures. The advantages of developed new coatings and the necessity of their use in modern gas turbine engines allow the metals to be used safely at high temperatures, which in turn can enhance the efficiency of gas‐turbine engine‐compressor sections.
The electrolytic saturation process was done in an aqueous bath with different effective parameters such as frequency, peak of applied pulsed voltage, etc. to obtain the desired nanostructures. Systematic characterization was carried out on as‐prepared as well as oxidized coatings and these results are presented. The performance of new coatings was evaluated by generating weight‐gain data as a function of time, followed by detailed characterization in order to confirm the ability of the coatings to prevent oxidation and alpha‐case formation. Potentiodynamic polarization and SEM nanograph analysis were undertaken to study corrosion resistance and the nanostructure of obtained layers.
The results showed that the corrosion and oxidation resistance of the obtained layers depended strongly to the average size of nanocrystallites and their nanomorphology. All coated samples had better electrochemical and oxidation behavior compared to the untreated substrate.
The results obtained in this research into nanocrystalline plasma electrolytic saturation can be used wherever good corrosion and oxidation resistances with high efficiency are required.
The speed of treatment by this technique makes this method very suitable for industrial surface treatment of different components.
