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Titanium and titanium alloys have excellent biocompatibility , corrosion resistance , mechanical properties and processing performance , to become one of the most widely used in biomedical metallic materials . Mainly used for the medical field of artificial joints , dental , orthopedic, cardiac surgery , body support frame . The titanium has a good resistance to corrosion , uniform corrosion , crevice corrosion, etc. However , in a non-oxidizing acid solution in dilute HCl, H2SO4 , etc. , exist . Complex physiological environment of the human body , but also easy to humoral erosion . Examples of the implantable material , need good abrasion resistance and blood compatibility, due to the biological material with the human blood contact portion of the main surface of the material , so to improve the corrosion resistance of the material , abrasion resistance and blood compatibility the key is the material surface . To solve the above problem , this paper adopts double glow plasma surface alloying technique , the surface of pure titanium Ti-Nb and Ti02 alloy layer is formed , and then take advantage of the OM , SEM , EDS, XRD analysis of the microstructure of the modified layer and tested its surface corrosion resistance , abrasion resistance and blood compatibility . Infiltration Nb and infiltration O after the uniform densification of the modified layer is formed in the surface of the titanium substrate , the infiltration Nb layer formed mainly an intermetallic compound of Ti-Nb . Seepage O layer formed Ti02. Two simulation artificial body fluid infiltration Nb and seepage O -modified layer titanium matrix increased the corrosion potential , corrosion current density decreases , the corrosion rate decreases , the corrosion resistance can be improved to a certain extent . Wear volume of the diffusion layer is smaller than the matrix , and the coefficient of friction were reduced by 0.57 to 0.27,0.45 . The wear scar depth and the width of the grinding marks are relatively small, of the titanium substrate shows good abrasion resistance . Infiltration Nb layer and permeate the wear volume of the O layer is reduced to 1/6 of the base body . Than the wear rates are reduced. Modified layer in the the dynamic coagulation time, the hemolytic ratio and the roughness test also showed good blood compatibility .
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