Corrosion resistance and friction of sintered NdFeB coated with Ti/TiN multilayers

Ti/TiN multilayers were deposited on sintered NdFeB by radio frequency magnetron sputtering. The film grain size decreased with the number of multilayers in the stack. Corrosion current density of sintered NdFeB with Ti/TiN multilayers was much lower than bare NdFeB. NdFeB with six periods of Ti/TiN multilayers exhibited good corrosion resistance in artificial saliva. Wear properties were characterized followed by the open circuit potential measurements. Friction and corrosion are interdependent. The Ti/TiN multilayers enhanced the corrosion resistance and decreased the wear volume. The joint action of corrosion and mechanical loading boosted the wear rate.