title: Electrophoretic deposition of double-layer HA/Al composite coating on NiTi.
abstract: In order to improve the bioactivity of NiTi alloys, which are being known as the suitable materials for biomedical applications, numerous NiTi disks were electrophoretically coated by hetero-coagulated hydroxyapatite/aluminum composite coatings in three main voltages from suspensions with different Al concentrations. In this paper, the amount of Ni ions release and bioactivity of prepared samples as well as bonding strength of the coating to substrate were investigated. The surface characterization of the coating by XRD, EDX, SEM, and FTIR showed that HA particles bonded by Al particles. It caused the formation of a free crack coating on NiTi disks. Moreover, the bonding strength of HA/Al coatings to NiTi substrate were improved by two times as compared to that of the pure HA coatings. Immersing of coated samples in SBF for 1 week showed that apatite formation ability was improved on HA/Al composite coating and Ni ions release from the surface of composite coating decreased. These results induce the appropriate bioactivity and biocompatibility of the deposited HA/Al composite coatings on NiTi disks.
authors.affiliation: Research Center for Advanced Materials and Mineral Processing, Faculty of Materials Engineering, Sahand University of Technology, Tabriz, Iran. Electronic address: E_karimi@sut.ac.ir.
authors.forename: Esmaeil
authors.initials: E
authors.lastname: Karimi
authors.affiliation: Research Center for Advanced Materials and Mineral Processing, Faculty of Materials Engineering, Sahand University of Technology, Tabriz, Iran.
authors.forename: Jafar
authors.initials: J
authors.lastname: Khalil-Allafi
authors.affiliation: Research Center for Advanced Materials and Mineral Processing, Faculty of Materials Engineering, Sahand University of Technology, Tabriz, Iran; Department of Mechanical Engineering, University of Bonab, Velayat Highway, P.O.Box: 5551761167, Bonab, Iran.
authors.forename: Vida
authors.initials: V
authors.lastname: Khalili
mesh_terms: D000497:Alloys / Q000737:chemistry*; D000535:Aluminum / Q000737:chemistry*; D020099:Coated Materials, Biocompatible / Q000737:chemistry*; D017886:Durapatite / Q000737:chemistry*; D007477:Ions / Q000737:chemistry / Q000378:metabolism; D008855:Microscopy, Electron, Scanning; D009532:Nickel / Q000737:chemistry* / Q000378:metabolism; D017550:Spectroscopy, Fourier Transform Infrared; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry*
chemical_list: D000497:Alloys; D020099:Coated Materials, Biocompatible; D007477:Ions; C040654:titanium nickelide; D009532:Nickel; D017886:Durapatite; D000535:Aluminum; D014025:Titanium
keywords: Electrophoretic deposition; HA/Al composite coating; Hydroxyapatite; NiTi alloys