Abstract
? 2022 Elsevier B.V.Nano-TiC powders were doped to increase the corrosion resistance of hot-deformed NdFeB magnets. Effects of the dopant content on their electrochemical corrosion behavior in sulphuric acid solutions were studied by various measurement techniques including potentiodynamic polarization, electrochemical impedance spectroscopy, scanning electron microscopy and X-ray photoelectron spectrometer. Results showed that low additions of nano-TiC especially at the optimum content of 0.5 wt% can obviously increase the resistances and reduce the corrosion current density. It is ascribed to the dopant hindrance effects on the dissolution of Nd-rich phases and the coverage increase of intermediate products on NdFeB substrate induced by nano-TiC that acted as the favorable sites for adsorption reactions. Maximum increase in inductive resistance and the corresponding reduction in current density were found to be 60.6% and 36.1%, respectively. In addition, the effect mechanism of nano-TiC on corrosion behaviors was discussed based on experimental results.
NSTL
Elsevier