Electrophoretic deposition of Hydroxyapatite on NiTi shape memory alloy

In this study, hydroxyapatite powders as a bioceramic were coated on NiTi shape memory alloy by electrophoretic method. Suspension solution used as a mixture of n - butanol and tri ethanol amine (TEA). Deposition was carried out at different applied voltages of 20, 30 and 40 volts in different times from 1 to 5 minutes and constant voltage on the cathode. After deposition, the samples were dried at room temperature for 24 hours. Then weight and thickness of coating were measured. Ultimately the samples were sintered at 800 ℃ in argon atmosphere for 2 hours. X-ray diffraction (XRD) and SEM were used for phase identification and morphological examining of coating consecutively. Composition of coating was analysied by Energy Dispersive X-ray (EDX).The results showed that a uniform, continuous and crack-free coating can be achieved at 30 volt and at shorter time after sintering. Moreover an increase in the deposition period, caused an increase in the weight and thickness of the deposition. The technique presented in this research can be a replacement technique for bioactive coatings in comparison with other techniques such as sol - gel and plasma spray coating.