Formation of Magnesium Films on Magnesium Alloys by Vapor Deposition Technique

In order to improve corrosion resistance of magnesium alloys, it has been attempted to coat the surface of the magnesium alloys with pure magnesium by vapor deposition technique. Commercial 3N-Mg and AZ91D alloy were evaporated at 1050 K in a stainless steel tube evacuated at about 10 exp -2 Pa, purified by a retort effect, and deposited on the surfaces of a substrate which was a magnesium alloy, AZ31. It is considered that isolated small particles of magnesium are firstly formed on the substrate, and then they grow having faceted planes to cover the surface of the substrate. The coated and uncoated specimens of AZ31 alloy were examined with salt immersion tests in 1% NaCl solution, which showed superior corrosion resistance of coated specimen to uncoated one.