| Based on the previous research,this paper investigates the technics of bioactive oxidation on Ti6A14V by micro-arc oxidationthe.The thesis is about micro-arc oxidation of Ti6A14V,based on lots of experiments applying micro-arc oxidation parameter under constant current condition.Influence of electronic parameters (current density,duty cycle,frequency and time) are studied on Ti6A14V coating thickness,surface and composition of phase in theβ-C3H7Na2 O6P·5H)O4 +(CH3COO)2Ca·H2O solution.Bioactivity and biocompatibility property of the film after treatment of different electronic parameters was analyzed by soak it into simulate body fluid and by anticoagulation evaluation and the generation of hydroxyapatite was induced by hydrothermal synthesis.The result showed,the growth and structure of Ti alloy oxidation coating can be affected obviously by current density,duty cycle with constant current and oxidation time,but not by frequency.The number and size of micropore are affected by the above four factors at the same time.With the increasing of oxidation time,duty cycle and current density,the number of micropore decreases,the size of micropore increases.This is opposite with frequency.XRD showed the oxidation coating is mainly composed of Anatase and Ruffle TiO2,the latter increses with the increase of the current density,amorphous phase formed as the entrance of Ca and P into the coating.Duty cycle and oxidation time have a similar influence to the the growth and composition of micro-arc oxidation.With the increase of the impulse frequency, thickness turns lower,size of micropore on the coating suface becomes less,but numbers gradually increase.When frequency is between 500Hz and 900 Hz, influence of impulse frequency is not so obvious to the relative content of Anatase and Rutile TiO2.The scratch adhesion test showed:bond between coating and matrix decreases with duty cycle increases and current density increases:while gradually increase with increase of frequency under constant current condition. Hydrothermal synthesis(HS) showed,different medium,temperature and disposed time affect the morphology,the quantity,distribution and the rime extent of the HA. Amorphous substance on the surface is transformed into the crystal HA.Stimulated Body Fluid immersion experiments showed:Ti alloy induces forming HA in the SBF after treated with MAO-HS.The quantity of HA increases with extension of time and the coating has good bioactivity.Haemocompatibility experiment finds that the blood clotting time of the coating is much longer than that of Ti alloy;and the platelet sticking number on the coating is obviously less than those on the Ti alloy.These indicate that the Haemocompatibility of the coating is remarkably superior to the Ti alloy.
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