The Study On The Aluminum Coating On The Magnesium Alloy Surface Obtained By Electro-arc Spraying

Magnesium is one of the elements which have the most abundance reserves. With the disappearing of most metal, the development of Magnesium is the most important measure to Sustainable development. As the third metal structural material after the steel and aluminum, Magnesium alloy is used widely in automotive, electronic , traffic ,aeronautical industries and national defense industries, because of a number of desirable features, including high strength/weight, high hardness/weight, damping characteristic, electromagnetism screen characteristic and recycled easily.However, because of the high chemistry characteristic, magnesium will be eroded in the self-atmosphere and ocean atmosphere. So their applications are limited severely for their low corrosion resistance. Their corrosion resistance must be improved to exert the merit of magnesium. There are two ways to improve the corrosion resistance. One is to add alloy element, the other is surface processing. But the popular way is surface processing today, including chemical conversion, microarc oxidation and electroless plating etc. But there are some disadvantages, including complicated technics, high cost, even the problem of the pollution of the environment. Magnesium alloy surface coating by electro-arc spraying aluminum is the measure to improving magnesium alloy corrosion resistance in this paper. Arc spraying is one of heat spraying, its energy is electricity. As self-consumed electrode, two wire produce arc by short circuit, which can fuse the metal by short circuit, and then, fused metal was pulverized to fused drop by compressed air. Fused drop was accelerated and felted on the group. Arc spraying has a lot of merit, such as high combine intensity, high efficiency, high quality, cheap equipment, easy to use and maintain. This paper is producing magnesium surface by arc spraying.First a protecting aluminum coating on the magnesium alloy surface was obtained by electro-arc spraying with different technics. The result shows that the coating is uniformity and dense and the interphase between the coating and group is unconspicuous with the technics which voltage is 30V and pressure is 0.6 MPa.