UTILISATION OF NATURAL HYDROXYAPATITE FROM WHITE BARRAMUNDI FISH SCALES (Lates calcarifer) TO INCREASE THE BIOACTIVITY IN THE TITANIUM ALLOY (Ti6Al4V) ELI WITH THE DIP COATING METHOD FOR BIOMEDICAL APPLICATIONS

Abstract

Ti6Al4V ELI is a titanium alloy that is quite widely used in medical applications for prosthesis implants. Ti6Al4V ELI has high corrosion resistance and good biocompatibility, but is less bioactive for new bone growth sites. Improving the bioactive properties of titanium alloys can be undertaken by coating them with hydroxyapatite. In this study, the type of hydroxyapatite used is a natural hydroxyapatite which is processed from local Indonesian ingredients, namely white barramundi fish scales (Lates calcarifer). White barramundi scales are a type of waste that contains high calcium, so they have the potential to be a source of hydroxyapatite. The purpose is to determine the characteristics of the natural hydroxyapatite layer on the mechanical properties and surface properties of the Ti6Al4V ELI titanium alloy. The hydroxyapatite coating was conducted by the dip coating method with a coating time of 10, 14, 24, and 30 seconds. The characterisation was carried out using a Stereo Microscope and SEM. The results showed that the hydroxyapatite layer met the thickness parameters in biomedical applications in 14 minutes with a layer thickness of 199 µm. This result is better than previous studies using the electrophoretic deposition method at a voltage of 7 V for 10 seconds where the layer thickness was 72 µm. This indicates that such a simple method of dip coating with an optimum parameter is applicable for coating titanium alloys with a natural hydroxyapatite.