Mechanical and Corrosion Properties of Porous Titanium Prepared by an Electro-Assisted Powder Metallurgy Approach

The sintering temperature and oxygen content significantly determine the properties of porous Ti prepared by the traditional powder metallurgy route. However, it is difficult to remove the surface oxide scale on the Ti powders. Herein, porous alpha-Ti is prepared by an electro-assisted powder metallurgical (EPM) method using Ti powders with different particle sizes in molten CaCl2 at 850 degrees C. The electrochemical polarization refreshes the boundaries of Ti particles and thereafter accelerates the diffusion rate of Ti atoms. The compressive strength of the EPM-Ti is 100-300 MPa, and the elastic modulus is smaller than or nearly 3 GPa. Moreover, the corrosion depth of the EPM-Ti-50 mu m is similar to 36 mu m after being soaked in Hanks' solution for 90 days. The corrosion potential is - 0.12 V (versus SCE), and the passivation current density is 5.14 x 10(-6) A cm(-2). Therefore, the porous EPM-Ti is a promising implant material with suitable properties for human bone.