FRICTION AND CORROSION-RESISTANCE OF SPUTTER-DEPOSITED SUPERSATURATEDMETASTABLE ALUMINUM-MOLYBDENUM ALLOYS

Two closed field unbalanced magnetrons with targets of aluminium and m olybdenum have been used for the co-deposition of aluminium-molybdenum coatings with different compositions. A pin on disk machine and a com puter controlled potentiostat have been used to evaluate respectively, the tribological and corrosion properties of the deposited alloys. Re sults have shown that introducing molybdenum into aluminium coatings i mproves their poor tribological properties. Aluminium-molybdenum coati ngs with different compositions have shown low wear behaviour and for coatings with high molybdenum contents (>80%) friction coefficients ag ainst steel, as low as 0.18 have been obtained. The addition of molybd enum into aluminium coatings has reduced their corrosion tendency and corrosion current density in a marine environment.