**2.3.3 Dynamic coagulation time test of TiNi SMA after surface modification**

The experiment on dynamic coagulation time is to test the degree of activating endogenous coagulation factor, the more smooth the dynamic coagulation curve is, the higher the absorbance at ordinate will be. This shows that, the longer the coagulation time, the lower the degree of activating coagulation factor. Generally, the time at O.D.=0.100 is often settled as the coagulation time, in order to comparing. Figure 2-5 shows the change curves of absorbance and blood connecting time of TiNi SMA, which were surface modified by anodically-oxidized and cathodically-electrodeposited respectively. It can be seen from the figure that the absorbance of the anodically-oxidized sample is highest, and the coagulation time is the longest. This illustrates that it has an excellent anti-coagulation property. The secondary is the cathodically-electrodeposited sample, and the last one is TiNi SMA sample (un-treated). Besides, material surface smoothness also has an effect on dynamic coagulation time. Generally the higher the surface smoothness, the longer the dynamic coagulation time.

Ti-O Film Cathodically-Electrodeposited on

anatase TiO2 with bioactivity was obtained.

solution to PH1-3, adding about 0.2M of NO3

**3. Conclusions of this paper** 

compatibility.

4min.

**4. References** 

416-421

346(1-2):291-307

the Surface of TiNi SMA and Its Bioactivity and Blood Compatibility 41

1. After anodic oxidization, TiNi SMA displayed a better thermodynamic stability and anti-corrosivity in simulant physiological environment, and improved blood

3. After cathodic electrodeposition, TiNi SMA displayed a better thermodynamic stability and anti-corrosivity in simulant physiological environment, and improved blood

4. Through the discussion for Ti-O film's morphologies and properties of TiNi SMA at different technics, the optimal technical parameters obtained were: blending Ti(SO4)2

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Fig. 2-5. Absorbance of modified TiNi SMA versus time
