Characterization of TiC/Ni Composite Immersed in Synthetic Seawater

This work shows the electrochemical study of nickel (Ni) and TiC/Ni composite immersed in synthetic seawater. In order to characterize the corrosion process, polarization curves (PC) were carried out. All electrochemical measures were made under static conditions, room temperature, atmospheric pressure and 24 hours exposure time. An electrochemical cell with a typical three-electrode array was used. Effect of TiC as reinforcement into the Ni matrix was evaluated. According PC results, it is possible to point out that the corrosion rate (CR) of the TiC/Ni composite was higher than Ni corrosion rate. The obtained results indicate that the corrosion process of both materials is of mixed type, that is to say a process of transfer of load influenced by a mechanism of mass transfer. Observations through scanning electron microscopy (SEM) revealed that mechanism of corrosion was cells of differential aeration (difference of concentration of oxygen). The corrosion morphology was localized type (pits and crevice).