**1.2.2.7 Effect of deposition time on the surface morphology and corrosion resistance of Ti-O film**

Depositing TiNi SMA respectively at a constant current density of 20mA/cm2 for different times and at another constant current density of 5mA/cm2 for different times, with an SZX-STAD2 type of OLYMPUS metallurgical microscope, the Ti-O films were observed, to investigate the effect of deposition times at the current densities of 20mA/cm2 and 5mA/cm2 respectively on Ti-O film morphology.


The experiment device used a standard trielectrode system. The signal generator used MEC-12 type of multi-function electrochemical analyzer. The reference electrode was SCE. The auxiliary electrode was a Pt one. The sample was connected with a wire, working area 10mm×10mm and non-working area coated with silica gel. The electrolytes were Hank's solution (PH7.45) and Fusayama one (PH6.13). The experiment used the staircase voltage scanning method, to compare and analyze the corrosion resistances of the TiNi SMA before and after cathodic-electrodeposition respectively in simulated physiological environment. **1.2.2.5 Effect of current density on the surface morphology and corrosion resistance of** 

With an SZX-STAD2 type of OLYMPUS metallurgical microscope, the Ti-O films obtained by cathodic-electrodeposition at different current densities for 4min respectively of TiNi SMA were observed, and the effect of the current densities on surface morphology of Ti-O

The corrosion potential and anodic polarization curve of SMA deposited at 20mA/cm2 and 5mA/cm2 in hank's solution and Fuayama solution were respectively tested, in order to

The samples of TiNi SMA deposited at 20mA/cm2 for 7min and 5mA/cm2 for 4min respectively were crystallized at 450C, with an SZX-STAD2 type of OLYMPUS metallurgical microscope, the Ti-O films before and after depositing respectively were observed, and the effect of crystallization treatment on Ti-O film morphology was

The TiNi samples deposited at 5mA/cm2 for 4min before and after crystallizing respectively were taken into Hank's solution (PH7.45) and Fusayama solution (PH6.13) to test their corrosion potential and polarization curve, in order to investigate the effect of crystallization

**1.2.2.7 Effect of deposition time on the surface morphology and corrosion resistance of** 

Depositing TiNi SMA respectively at a constant current density of 20mA/cm2 for different times and at another constant current density of 5mA/cm2 for different times, with an SZX-STAD2 type of OLYMPUS metallurgical microscope, the Ti-O films were observed, to investigate the effect of deposition times at the current densities of 20mA/cm2 and

investigate the effect of current density on corrosion resistance of Ti-O film.

**1.2.2.6 Effect of crystallization treatment on the surface morphology and corrosion** 

**1.2.2.4 Potentiodynamic polarization test of the material in simulated physiological** 

Sample interval (mV)

Scanning rate (mV/min)

Stop potential (V)

Start potential (V/SCE)

**environment** 

**Ti-O film** 

film were investigated.

**resistance of Ti-O film** 

treatment on corrosion resistance of Ti-O film.

5mA/cm2 respectively on Ti-O film morphology.

investigated.

**Ti-O film** 

Table 1-1. Parameters of dynamic polarization test
