Micro-arc oxidation of bioceramic coatings containing eggshell-derived hydroxyapatite on titanium substrate. Issue 15 (15th October 2019)

• Record Type: Journal Article
• Authors: Qaid, Tawfik Hamood; Ramesh, S.; Yusof, F.; Basirun, Wan Jeffrey; Ching, Y.C.; Chandran, Hari; Ramesh, S.; Krishnasamy, S.
• Is Part Of: Ceramics international. Volume 45:Issue 15(2019)
• Page Start: 18371
• Page End: 18381
• Publication Date: 2019-10-15
• Subjects: Eggshells-derived hydroxyapatite -- HA -- Titanium -- Ti6Al4V -- Micro-arc oxidation (MAO); Ceramics -- Periodicals; Céramique industrielle -- Périodiques; Ceramics; Periodicals; Electronic journals; 666
• DOI: 10.1016/j.ceramint.2019.06.052
• Languages: English
• ISSNs: 0272-8842

Abstract

Abstract: In the present study eggshells-derived hydroxyapatite (EHA) coatings were successfully produced on Ti6Al4V substrates using micro-arc oxidation process (MAO) at various concentrations of EHA (i.e. 1, 1.5 and 2 g/L) in an electrolyte consisting of tri-sodium orthophosphate. The attributes of the coatings were determine by X-ray diffraction, attenuated total reflectance-fourier transform infrared spectroscopy, field emission scanning electron microscopy and energy dispersive X-ray spectroscopy. The adhesion strength was evaluated using micro scratch tester, while the corrosion behavior of the MAO-coated substrates in phosphate buffer solution was determined by an electrochemical method. The results showed that as the EHA concentration increased, this was accompanied by a reduction in the porosity due to the formation of a dense and thick coating layer. This has also resulted in an increased in the surface roughness and degree of crsytallinity of the HA phase. The MAO-coated substrate prepared with 1.5 g/L EHA concentration exhibited a well-formed coating layer with improved adhesive strength and excellent corrosion resistance. The mechanism of EHA-coating formation as well as the enhanced corrosion resistance of the coated substrates were discussed. This research shows the viability of using calcium-rich waste eggshells to produce phase pure HA suitable for coating on Ti6Al4V substrate using MAO method.