M R Tavighi - Advanced Materials Engineering Research Center, Karaj Branch, Islamic Azad University, Karaj, Iran
A Rabieifar - Advanced Materials Engineering Research Center, Karaj Branch, Islamic Azad University, Karaj, Iran
O Ashkani - Faculty of Technology and Engineering, Science and Research Branch, Islamic Azad University, Tehran, Iran
A Asaadi-Zahraei - Faculty of Materials Science and Engineering Khajeh Nasir Toosi University, Tehran. Iran

In this research, plasma electrolytic oxidation (PEO) was prepared at duty voltage of ۳۵۰ and ۴۵۰ V and processing time of ۵and ۱۰ minutes on Ti-۶Al-۴V alloy in Na۲SiO۳ + KOH electrolyte. Then, the adhesion strength and microstructuraldegradation of the coating surface were investigated through a constant load scratch test, field-emission scanning electronmicroscope (FE-SEM), and X-ray diffraction (XRD), respectively. The results showed that while increasing the processingtime and duty voltage, the density of porosity and the amount of rutile on the coating surface increased. Meanwhile,microstructure degradations like delamination, gross spallation, and buckling spallation decreased due to increased adhesionstrength. This resulted from an increase in voltage and processing time.

Plasma Electrolytic Oxidation (PEO), Ti۶Al۴V Alloy, Scratch Test, Degradation Mechanisms