Laser-induced electrochemical characteristics of aluminum alloy 2024-T3

Laser-induced surface modification of aluminum alloy 2024-T3 was investigated as laser intensity dependence of surface composition and patterning related to electrochemical characteristics using techniques of environmental scanning electron microscopy (ESEM), potentiodynamic scan, and electrochemical impedance spectroscopy (EIS). Analysis of surface composition using ESEM and EIS indicated that laser fluences in a range of 1.1-1.3 j/CM2 were found to preferentially reduce the copper concentration in the alloy surface to approximately 0.1 wt % and grow the oxidized layer on the surface. Surface composition and patterning were accordingly correlated to electrochemical characteristics of corrosion resistance, capacitance, and potential, which were subsequently used to calculate the corresponding thickness of the formed oxide layer. An enhancement of corrosion resistance characteristics of the 2024-T3 aluminum alloy was attributed to the combination of laser-induced copper removal and oxide layer formation on the surface. (C) 2004 Laser Institute of America.