Decay of cold plasma properties on aluminium surfaces in time

Cold plasma treatment represents an efficient, clean and economic alternative to activate aluminium alloy surfaces. It allows to simplify the anticorrosive protection process of aluminium alloy surfaces and, therefore, to reduce their manufacturing costs. The aim of this work has been to value the aging time of cold plasma treatment, applied to aluminium alloy surface, as a function of process parameters. A set of process variables (voltage, time and air flow rate) has been identified and used to carry out some experimental tests on the basis of Design of Experiment techniques. Aluminium alloy wettability has been quantitatively characterised by the standard procedure detailed in ASTM D724 along the aging time. A SEM analysis has been carried out in order to study the surface changes of aluminium alloy connected with aging time. The cold plasma process has proved to give a long aging time in all process conditions.