Improvement of Corrosion Behavior of Nanostructured Ni Coating by Jet Electrodeposition and Laser Remelting

Abstract

An effective method to improve corrosion resistance for the nickel coating on the stainless steel(1Cr18Ni9) is described. The nickel coating was predeposited on the 1Cr18Ni9 by using the jet electrodeposition technology. Then the laser remelting was conducted on the predeposited Ni coating in order to strengthen the coating’s microstructure and the interface between the substrate and the Ni coating. The experimental results revealed that, at current density of 40 A/dm2, the deposited coating had the optimal corrosion resistance because of refined grains and dense interior-structure. After laser remelting, the bonding state between the coating and substrate evolved to a new metallurgical combination from originally mechanical combination. The corrosion rate comparison indicated that Ni coating with compound process of jet electrodeposition and laser remelting had higher corrosion resistance compared with bare 1Cr18Ni9 as well as jet electrodeposited Ni coating.