Corrosion behavior of Ti6Al4V ELI coated by bioceramic HA in artificial saliva at fluctuating temperatures

Abstract

Titanium and titanium alloy have been used widely in both orthopedic and orthodontic applications. Dental implant in orthodontic is utilized to replace the missing teeth through implanting them into the human jaw as a teeth root. Ti6Al4V is one of a titanium alloy that has been developed as a dental implant due to its mechanical strength, corrosion resistance, and bio-compatibility. Hydroxyapatite is applied as the coating material is significantly a solution to overcome the inert properties of Ti6Al4V and becomes bioactive. The study goal is to determine the corrosion rate of Ti6Al4V ELI coated nano-sized hydroxyapatite using electrophoretic deposition (EPD) method applying the 5 V voltage and in 5 minutes. The implant was soaked in a solution of artificial saliva for six weeks at fluctuated temperature, 20°C and 60°C. The results showed that the corrosion rate decreased from 1.1413 mpy to 0.4236 mpy because of hydroxyapatite coating. By the hardness properties also decreased from 318 HVN into 203 HVN. This indicated that the nano-hydroxyapatite might inhibit corrosion behavior and during corrosion process occurred the implant was not able to maintain its mechanical properties.