Characterization of ‎bioactivity behavior and corrosion responses of hydroxyapatite-ZnO nanostructured coating deposited on ‎NiTi shape ‎memory alloy‎. Issue 17 (1st December 2018)

• Record Type: Journal Article
• Authors: Sabzi, Masoud; Far, Sadegh Moeini; Dezfuli, Saeid Mersagh
• Is Part Of: Ceramics international. Volume 44:Issue 17(2018)
• Page Start: 21395
• Page End: 21405
• Publication Date: 2018-12-01
• Subjects: NiTi shape memory alloy -- Biological Compatibility -- Hydroxyapatite-ZnO -- Corrosion Resistance -- Electrophoretic Deposition Process (EDP); Ceramics -- Periodicals; Céramique industrielle -- Périodiques; Ceramics; Periodicals; Electronic journals; 666
• DOI: 10.1016/j.ceramint.2018.08.197
• Languages: English
• ISSNs: 0272-8842

Abstract

Abstract: In this research, a ceramic combination of Hydroxyapatite and ZnO with a weight ratio of ‎‎50:50 was deposited on NiTi shape memory alloy by Electrophoretic Deposition Process ‎‎(EPD). Deposition of the Hydroxyapatite-ZnO on NiTi alloy was performed by applying 50 ‎volts for 100 s. The sintering operation was then conducted for 2 h in a furnace ‎under an argon atmosphere at 500 °C. In the next step, the morphology and thickness of the ‎coating were studied by Field Emission Scanning Electron Microscopy (FE-SEM). In addition, ‎bioactivity behavior and corrosion resistance of the coating were evaluated using ‎electrochemical tests, and the rate of the Ni ion release has been investigated in ‎Simulated Body Fluids (SBF) solution. The FE-SEM observations on the morphology of the ‎Hydroxyapatite-ZnO ceramic nanostructured coating revealed that a non-crack coating with ‎approximate 135 µm thickness was deposited on the NiTi alloy. The results also ‎showed that the Hydroxyapatite-ZnO nanostructured coating leads to the formation of ‎ion exchange barrier on the NiTi alloy surface which acts well as a barrier to penetrating ‎nickel ions in the body fluid, in such a way that the corrosion resistances of NiTi alloy has been ‎increased significantly in the presence of Hydroxyapatite-ZnO coating. Also, the adhesion ‎strength of the Hydroxyapatite-ZnO ceramic nanostructured coating on NiTi shape memory ‎alloy was highly desirable (about 25.4 ± 0.1 MPa).‎