Abstract: The concentration gradient of strontium-doped brushite coatings was prepared by two steps electrochemical depositions on the surface of medical titanium alloy(Ti-6Al-4V),which provided valuable theoretical reference for the clinical application and further experimental research of titanium(alloy)coating.The chemical compositions of coatings was analyzed by X-ray diffractometer(XRD),and the concentration of doped strontium was examed by X-ray fluorescence spectrometer(XRF).Field emission scanning electron microscopy(SEM)was used to examine the morphology of strontium-doped brushite coatings.The biocompatibility of strontium-doped brushite coatings was judged preliminarily by hemolysis rate that was tested by hemolysis test in vitro.The concentration of strontium was calculated according to the ratio of n(Sr)/n(Sr+Ga).Our results showed the concentrations of strontium-doped for strontium-doped brushite coatings were the percent of 10,15 and 20.The SEM images showed that the morphology of coatings was regular and compact.The rate of hemolysis was less than 5%,which was in accordance with the requirements of medical materials(<5%).

Key words: medical titanium alloy, electrochemical deposition, strontium, brushite, coating