Abstract

Surface protection method for magnesium alloy based on using organic coating and electroless plating

Author(s): Yucheng Liu, Yubin Liu

Aimed at the traditional surface treatment technology failing to conduct the electrochemical protection for the magnesium alloy, the paper proposed a novel method of the surface protection for the magnesium alloy based on using the organic coatings and electroless plating. In this method, firstly the organic coating is coated on the surface of magnesium alloy, secondly then chemical copper plating for the magnesium alloy was carried out. Therefore, during the chemical plating, copper will be deposited on the organic coating surface. The organic coating enable the substrate can not directly contact copper coating so as to avoid the occurrence of galvanic corrosion. The metallized filmsray diffraction and scanning electron microscope analysis were used to research the morphology of the interlayer and plating film. The research results showed that the films have a rather perfect compact structure. The potentiodynamic polarization curves for corrosion study of the coated magnesium alloys were also performed in a corrosive environment of NaCl solution. Polarization curve test results verified that comparing with the substrate, the corrosion resistance of coated magnesium alloys increases greatly. In addition, the environmental pollution can be avoided because of using the sodium hypophosphite instead of formaldehyde as the reducing agent.