STUDY OF HYDROXYAPATITE COATINGS ON TITANIUM FOAMS USING PULSED LASER DEPOSITION (PLD)

Abstract

This study primarily focuses on the synthesis of Hydroxyapatite powder, the development of its coating on titanium foams using the pulsed laser deposition coating technique and the testing of coating parameters i.e. surface roughness, hydrophilicity, topography etc. followed by thorough evaluation for their use as biomedical implants. In the biomedical field, metallic prosthesis and implants are extensively used. Among these, titanium and its alloys are most widely used. But there are some of its short-comings such as stress-shielding induced aseptic loosening which can be overcome by coating it. It is often used for implantation purposes in the form of foams which reduces its density and Young’s Modulus. In this research, titanium foams have been coated with hydroxyapatite which is originally a ceramic material having excellent biocompatibility and bioactivity as it resembles the bone apatite in terms of its composition. Hydroxyapatite has been synthesized by the wet/homogeneous precipitation method with Calcium hydroxide, phosphoric acid, and deionized water as the primary precursors. HA has been characterized for purity and particle size determination and morphology using Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR), Energy Dispersive X-Ray Spectroscopy (EDS), and Raman Analysis. The coating has been done using Pulsed Laser Deposition (PLD) as the process is economically feasible and has optimum coating thickness control. Additionally, the coating has been tested for hydrophilicity (contact angle), surface roughness, and the surface morphology using Drop Shape Analyzer, Optical Profilometry, and Scanning Electron Microscopy (SEM) respectively. The results prove the effectiveness of Hydroxyapatite coating as it imparts enhanced biocompatibility to titanium foams and helps prevent stress-shielding induced aseptic loosening.