Functionally Graded Antibacterial Biomaterial Coatings for Titanium Base Alloy

Abstract

Abstract Metal implants made of titanium and its alloys need surface modification operations because they are weak in terms of osseointegration and to protect them from corrosive body fluids and the growth of harmful bacteria that prevent them from performing their function and cause their failure. Hydroxyapatite and titanium dioxide have proven high efficiency by using them as biological and anti-bacterial coating. The basis of the current study is to deposit a functionally graded ceramic coating of titanium dioxide and hydroxyapatite on a Ti6Al4V substrate by electrophoretic deposition (EPD) method at room temperature with optimal conditions of 20 volts and a deposition time of 1 minute, and then sintering in an atmosphere of argon at a temperature of 950°C for one hour. In addition, polarisation, open circuit, anti-bacterial activity, XRD, SEM, EDS was conducted. The laboratory results showed that the corrosion rate decreases for the coated samples compared to the uncoated. As for the SEM examination, the cross-section images showed that the gradient coating is dense, cohesive and free from microscopic cracks. Also, the surface images showed that the surface was uniform. In terms of XRD, the results showed the presence of rutile, anatase, and hydroxyapatite phases in addition to α_CaPO and β_TCP as a result of HAp decomposition. For the anti-bacterial examination, the findings revealed that the coating is anti-bacterial.