Electrochemical behavior of equal channel angular pressed titanium for biomedical application

Equal channel angular pressing method is one of the prominent severe plastic deformation techniques to obtain ultrafine grained and even nanostructured metals and alloys by imposing intense plastic strain. As known, pure titanium can be a suitable candidate for biomedical applications because it does not release any toxic ions into the body fluids and also, its biocompatibility properties. The present investigation deals the corrosion behavior of commercial pure titanium before and after ECAP process up to 10 passes by route BC at the 250°C in the 0.9% NaCl solution. The electrochemical results revealed that the corrosion resistance of titanium sample is improved by adding pass number because of the fabrication of passive oxide layer on the surface of the material. It is found that about 92% reduction at the corrosion rate magnitude and also, approximately 41% improvement at the hardness value have been achieved at the final pass as compared to the annealed condition. Furthermore, it is observed that the passive film on the surface of final pass sample is dense and integral with uniform structure, while the as-received one has some rarefactions and does not have very uniform surface.