Potential of electrical discharge treatment incorporating MWCNTs to enhance the corrosion performance of the β-titanium alloy.

The study presents the surface modification of β-titanium alloy by the electrical discharge chemical treatment (EDCT) to achieve a corrosion-resistant surface. This technique incorporated multi-walled carbon nanotubes (MWCNTs) in the dielectric medium to alter the surface properties of the substrate. Herein, the MWCNTs act as potential candidates due to its chemical inertness and physical as well as electrical properties for achieving desired surface properties. For the sake of comparison, the μ-hydroxyapatite (μHAp) powder was also utilized in the dielectric medium. Surface morphology, topography, and elemental composition of the treated surfaces were investigated by FE-SEM, EDS, and XRD techniques, respectively. The electrochemical potentiodynamic test was carried out to investigate the corrosion resistance of untreated and treated surfaces. The treated surfaces were also evaluated in terms of change in surface morphology, wettability, and surface free energy. The outcome revealed that the alloy treated with MWCNTs favors the synthesis of the chemically stable corrosion-resistant surface. The existence of TiO₂, ZrO₂, Nb₂O₅, TaO, ZrO_2, TiC₂, and NbC phases detected from XRD examination affirmed that the corrosion resistance of the substrate is significantly affected by multi-walled carbon nanotube deposition. The MWCNT-treated surface presented the improved wettability and surface free energy which are twofold higher than the untreated surface. [ABSTRACT FROM AUTHOR]