Fe3O4/T-ZnOw composites are fabricated by depositing a layer of Fe3O4 film on the surface of tetrapod-shaped ZnO whisker （T-ZnOw） by ferrite plating method. The morphology, structure and magnetic properties of the composites are characterized by scanning electron microscopy （SEM）, X-ray diffractometer （XRD） and vibrating-sample magnetometer （VSM）, respectively. The effects of temperature and pH value of fertile plating on the Fe3O4/T-ZnOw composites and the magnetic properties of composites are studied. It is shown that the chemical enviromnent with pH value at 7.5 is most favorable for the ferrite plating processes by analyzing the main peaks intensity of Fe3O4 in the XRD patterns and the average diameters of the Fe3O4 crystalline. The increase of the ferrite plating temperature with pH value around 7.5 benefits the whole encapsulation of T-ZnOw by the Fe3O4 magnetic films. The composites exhibit ferromagnetic properties and show much lower magnetization intensity than bulk samples at the same magnetic field intensity.
The electrochemical behaviours of titanium alloy Ti-10V-2Fe-3Al after electropolishing in a self-developed electrolyte in comparison with conventional grinding were studied by electrochemical impedance spectroscopy （EIS）.Optical microscopy （OM）,scanning electron microscopy （SEM）,atomic force microscopy （AFM） and X-ray photoelectron spectroscopy （XPS） were used to evaluate the surface characteristics of the alloy.It was found from the EIS experiments that the polarization resistance （Rp） was increased,the double layer capacitance （Qc） was decreased and the electrochemical impedance of the alloy was enhanced by electropolishing.The electropolished surface was flat,smooth and bright and its roughness was 3.310 nm.To underline the advantage of electropolishing process against grinding to provide the anodic oxidation process with a higher quality substrate,the ground and electropolished titanium alloys were anodized in parallel under the same conditions.The corrosion behaviours of the two kinds of anodized titanium alloys were compared.It was revealed that electropolishing generated a high quality substrate and improved the corrosion resistance of anodic oxide film formed on titanium alloy Ti-10V-2Fe-3Al.Furthermore,the mechanism of electropolishing improving the corrosion resistance of the anodic oxide film was proposed.
