Abstract
Microstructure and phase composition of the ceramic coatings formed on Ti–6Al–4V alloy by alternating-current microarc oxidation in aluminate solution were investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Distributions of nanohardness, H, and elastic modulus, E, along the coating thickness were determined using a nanoindentation method. After microarc oxidation treatment, the microstructure in the Ti–6Al–4V substrate near the coating/metal interface has not been changed; meanwhile, the titanium substrate has hardly absorbed oxygen atoms. The oxide coating is mainly composed of TiO 2 rutile and TiAl 2O 5 compounds. The rutile fraction in the inner layer coating is much higher than in the outer layer. On the contrary, the TiAl 2O 5 phase has a higher fraction in the outer layer. On the other hand, the nanoindentation test shows from the coating surface to the interior of the coating that the H and E gradually increase. The maximum H and E in the coating can reach 13 and 230 GPa, respectively. The changes of TiO 2 and TiAl 2O 5 contents along the coating thickness determine the H and E profiles in the coating.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
