Electrodeposition of Transition Metal-Aluminum Alloys from Chloroaluminate Molten Salts

摘要

The electrodeposition of transition metal aluminum alloys was investigated in the room temperature chloroaluminate ionic liquid, aluminum chloride-1-methyl-3 -ethylimidazolium chloride. Alloys that were investigated include the binary systems, Cu-Al, Ag-Al, Al-Ti, Al-V, Al-Mo, Al-Zr, Al-Nb, and Al-W, and the ternary system Al-Mo-Mn. Those alloys in which the transition metal predominates, Ag-Al and Cu-Al, were thermodynamically unstable in the plating bath and did not form chloride-free, compact coatings during electrodeposition. However, those alloys in which the transition metal was a minor component, e.g., Al-Ti, Al-V, Al-Mo, Al-Zr, Al-Nb, and Al-W, were electrodeposited as compact, nearly specular films. Many of these alloys, notably Al-Mo and Al-W, exhibited outstanding resistance to chloride-induced pitting corrosion, making them useful corrosion protective coatings for Air Force applications in high-salt environments.