Study of Aluminum Coating Thermally Sprayed on AZ80 Magnesium Alloy Surface
Aluminum (Al) coating was thermally sprayed on the surface of AZ80 magnesium (Mg) alloy. The Al-coating was deformed at 400°C with different deformation degrees of 15%, 30%, 45%, 60% and 80%. The corrosion properties of the AZ80 Mg alloys coated with Al-coatings were studied by potentiodynamic and galvanic tests in 3.5% NaCl solution; the adhesion strengths between Al-coatings and AZ80 substrate were also measured simultaneously by tensile test. The results showed that, Al-coating could decrease the corrosion rate of AZ80 Mg alloys, and the corrosion rate was related not only with the density of Al-coating but also with the adhesion strength of Al-coating. Before the formation of dense Al-coating, the corrosion rate of Al-coated AZ80 Mg alloys decreased with the increasing of bonding strength of Al-coating; after the formation of dense Al-coating, the corrosion rate of Al-coated AZ80 Mg was mainly determined by the structure of Al-coating. It was also revealed that with the increasing of deformation degree, the corrosion rate of the Al-coated AZ80 Mg alloys first decreased then increased, while the adhesion strength increased gradually. The corrosion rate of AZ80 Mg alloy coated with 60% deformed Al-coating was the lowest, which was only 19% of that of the AZ80 substrate.
Yafang Han, Fusheng Pan, Jianmao Tang, Chungen Zhou
H. Y. Xu et al., "Study of Aluminum Coating Thermally Sprayed on AZ80 Magnesium Alloy Surface", Materials Science Forum, Vol. 686, pp. 319-324, 2011