Natural hydroxyapatite (HA) was coated on NiTi alloy using electrophoretic
deposition method to improve the corrosion resistance and biocompatibility.
Coating process was performed at 120 s in various applied voltages of 40, 60,
and 80 V. Sintering process was done at 800 8C under inert gas for 2 h.
Electrochemical behavior of the coated samples was investigated in simulated
body fluid by using electrochemical impedance spectroscopy and polarization
tests. Furthermore, the nickel ions release from NiTi and HA coated-NiTi samples
were analyzed by atomic absorption analysis. Ultimately, scanning electron
microscopy micrographs and X-ray diffraction patterns were used to evaluate
the morphology and phase analysis of HA coatings. The results show that the
sample coated at 60 V reveals a uniform, dense coating accompanied with a
higher corrosion resistance. Moreover, after 4 weeks, nickel ions release was
reduced to 0.205mg/cm2 for coated sample at 60 V.