The sintered and bonded NdFeB permanent magnets are very important for their coercivity and magnetic specific energy [1, 2, 3], as well as opening new applications domains leading to miniaturization and improvement of performances of magnetic systems. It is well known that one important problem of the sintered NdFeB permanent magnets is the low corrosion resistance especially in the wet environment. The Nd-rich inter-granular phase, which play a important role in the coercivity mechanisms, in the presence of humidity and temperature is transformed into hydrides, which are brittle and lose their magnetic and mechanic properties. In order to increase the corrosion stability there are, in general, followed the following ways: to improve the microstructure or to protect the exterior surfaces of the magnets. The present work deals with the optimization of the anticorrosive protection technology of the sintered NdFeB permanent magnets by Zn-plating method using a rotary hexagonal drum as cathode and Zn-plates as anode in an electrolyte stationary base (zinc chloride, potassium chloride). The obtained anticorrosive protective Zn-layer’s performances were tested by functional and structural tests.



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