Electrochemical behaviour in synthetic saliva of silane coated Ni/Cu/Ni Nd-Fe-B magnet for dentistry applications

In this work the electrochemical behaviour in synthetic saliva of silane coated Ni/Cu/Ni Nd-Fe-B magnets for dentistry applications was assessed. A protective multilayer of N-propyl-trimethoxy-silane was deposited by dip-coating onto Ni/Cu/Ni Nd-Fe-B magnets. The corrosion process of the silanised magnets was experimentally studied by polarization and electrochemical impedance spectroscopy tests performed at increasing immersion time in synthetic saliva solution. The Ni/Cu/Ni plated cover is not able to provide good barrier protection in this electrolytic media, while an additional three-layer silane film guarantees better anti-corrosion properties and durability in synthetic saliva solution.