Electrochemical corrosion behavior of dual-main-phase CeNdFeB magnet

With the increasing of the sintered NdFeB magnet application, there is a great deal of the demand of Nd, consequently the price of Nd is rising. Therefore, it is necessary to produce a novel sintered NdFeB magnet at low costs. In this paper, the dual-main-phase CeNdFeB magnets were prepared. The corrosion potential of Ce is -2.48V, which is lower than that of Nd (-2.41V). But Ce is much cheaper than Nd. Thus, we compared the electrochemical corrosion behaviors of the sintered N45 and the sintered Ce-NdFeB magnet, whose magnetic properties is equivalent with the former. All experiments were performed in a standard three-electrode cell, which consists of specimens as working electrode, saturated calomel electrode (SCE) as reference, and Pt as counter electrode. The specimens were immersed in the electrolyte for approximately 30 min prior to be tested. The test electrolyte was neutral 3.5 wt% NaCl solution and tap-water, and the temperature was maintained at 25.