عنوان	Characterization and corrosion behavior of graphene oxide-hydroxyapatite composite coating applied by ultrasound-assisted pulse electrodeposition
نوع پژوهش	مقاله چاپ شده
کلیدواژه‌ها	Graphene oxide Hydroxyapatite Electrodeposition Ultrasonic waves Mechanical properties Corrosion resistance
چکیده	Hydroxyapatite (HA) coating reinforced with graphene oxide (GO) had been developed for getting rid of restrictions associated with its brittleness. This study introduced a promising method of ultrasound-assisted pulse electrodeposition to fabricate the GO-HA coating on the anodized heat-treated surface of titanium. The SEM images indicated that the combined effect of employing ultrasonic waves and GO as a second mechanically resistant phase resulted in the formation of a fine and compact microstructure for the HA-based coating. The EDS elemental maps and micro-Raman spectra showed that the ultrasonic power of 60 W was more effective to incorporate the GO sheets into the coating. However, aggressive agitation of electrolyte with increasing the power to 100 W limited the electrocrystallization of HA crystals in some regions of the surface. The results of nanoindentation test demonstrated the highest nano-hardness (3.08 Gpa) and elastic modulus (41.26 Gpa) for the GO-HA coating prepared by the ultrasound-assisted method. The EDS and FTIR analyses revealed that both the GO sheets and highly reactive OH· radicals produced during the water sonolysis had a positive influence on the mineralization of HA phase. In addition, the pore size distribution diagrams calculated from the N2 adsorption-desorption isotherms indicated a decrease in the pore size of HA crystals for the electro-codeposited GO-HA sample. Finally, anodizing/heat-treatment process and the incorporation of GO sheets into the coating led to a significant improvement in the corrosion protection of titanium.
پژوهشگران	لیلا فتح یونس نژند (نفر اول)، جعفر خلیل علافی (نفر دوم)