Electrodeposited zn-nanoparticles composite coatings for corrosion protection of steel

Abstract

In the field of galvanic plating, one of the ways to obtain metallic coatings with improved mechanic and anti-corrosion properties consists in the electrolytic entrapment of inert nanoparticles (e.g., oxides, carbides, carbon nanotubes, polytetrafluoroethylene etc.) in the metallic matrix. The particles confer to the resulting composite layers improved corrosion and wear resistance, increased hardness, superior tribologic properties, better subsequent adhesion of paintings and increased lifetime. Due to the fact that the nanosized particles possess special properties which could be transferred to the composite layers, there is a lot of research directions to be investigated, beginning with the exceptional properties of deposited layers and finishing with the incompletely elucidated electrodeposition mechanism. In this context, recent advances in electrodeposition of metal-matrix composite coatings will be reviewed with emphasis on electrolytic co-deposition of Zn with nanoparticles of TiO2, CeO2, ZrO2 etc. The factors influencing the co-deposition and the properties of the resulting composite coatings are also briefly discussed.