Corrosion, wettability and thrombogenicity investigation of ion beam modified HAP/Al2O3

Abstract Hydroxyapatite Ca 10 (PO4) 6 (OH) 2 , is a biosensitive ceramic which promotes bone growth in human fluid. However due to its weak mechanical strength it is often coated on chemically inert material such as alumina. In the present work hydroxyapatite (HAP) of thickness 1 μm is deposited on alumina using sol–gel process and the stoichiometric ratio of Ca:P = 1.67 is maintained. Surface property of HAP is further improved by Ar + ion implantation. The samples were irradiated with 1.4 MeV Ar + ions with fluence ranging from 5 × 10 14 to 1 × 10 16 ions/cm 2 . After irradiation, the surface is characterized using Atomic Force Microscope (AFM), Scanning Electron Microscope (SEM), electron dispersive X-ray spectroscopy (EDX), Glancing incidence X-ray diffraction (GXRD) and Rutherford backscattering Spectroscopy (RBS) techniques. Corrosion resistances and impedance analysis were carried out in Ringer solution. RBS and EDX were used to confirm the stoichiometric ratio of the film. Compound formation before and after ion implantation was studied using GXRD. Nanohardness, wettability and thrombogenicity of all the samples were studied. Correlation among surface morphology, improvement in corrosion resistance, hardness, wetability and thrombogenicity before and after ion implantation are discussed in this paper.