Introducing natural hydroxyapatite-diopside (NHA-Di) nano-bioceramic coating

Abstract

In the presented study, the deposition of nanostructured NHA-Di (natural hydroxyapatite-diopside) composite coatings on the surface of Ti-6Al-4 V implants is studied. The effect of electrophoretic deposition (EPD) voltage, Di content and process temperature on the surface roughness is also investigated. The powders are characterized by X-ray diffraction (XRD), fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray fluorescence (XRF). The atomic force microscopy (AFM) is also used to study the surface topography. According to SEM observations, there are hard agglomerates in the NHA-Di composite powders at low percentage of Di; however they are broken down by increasing the amount of Di percentage. Images which were obtained from the 2D AFM analysis of the NHA-Di coating after its deposition on Ti alloy specimen surface, indicated that the Roughen diagram fluctuates between the range of -0.03 and 0.01 mu m under the conditions that the Di content reaches 30 wt%. A specific load is applied during the adhesion test which resulted in NHA-30 wt% Di coating maintain its impeccability while the NHA-0 wt% Di coating samples were damaged.A graph is also developed based on the Hertz stress which proved to be challenging in terms of chemical stability based on its surface roughness. (C) 2015 Elsevier Ltd and Techna Group S.r.l. All rights reserved.