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NdFeB magnets were highly susceptible to corrosion in various environments.Protective Zn-Ni coatings electrodeposited on NdFeB permanent magnets from weak acid solutions were investigated in this paper.The influences of the main electroplating technological parameters including current density,bath pH,bath temperature and the [Ni]/[Zn] concentration ratio on the structure and chemical composition of Zn-Ni alloys coatings were studied.The optimum protective ability of Zn-Ni coatings to the NdFeB magnets were obtained with the Ni content up to 13 %,which depend on bath composition and operating conditions.The corrosion resistance properties were evaluated by whole-immersion and electrochemical testing in 3.5 % NaCl solution.The micro-morphology and composition of Zn-Ni coatings were analyzed using SEM,EDS and XRD.The experimental results indicated that the Zn-Ni coatings were predominant anodic type coatings for NdFeB magnets,and could provide electrochemical protection,barrier protection and passivation protection to the substrate materials.And the corrosion resistance of Zn-Ni coatings was raised in comparison with the electroplating Zn coatings.