Corrosion behavior of selective laser melted 6061 aluminum alloy electrodes for aluminum-air battery

6061 aluminum alloy can be used as an anode for aluminum-air batteries. Compared with cast one, three-dimensional (3D) printed aluminum alloy shows more flexible design and production process. Moreover, the self-corrosion behavior of 3D printed aluminum alloy without grinding its surface layer in alkaline solutions (electrolyte for aluminum-air batteries) is unclear. Here, the comparison between 3D-printed and cast 6061 aluminum alloy is investigated by self-corrosion testing, potentiodynamic polarization, electrochemical impedance spectroscopy, and hydrogen bubble visualization experimentation. The results show that although the corrosion resistance of the 3D-printed 6061 aluminum alloy decreases rapidly with time, it exhibits higher corrosion resistance at the initial stage of corrosion than that of cast 6061 aluminum alloy due to the "fish scale" layer and may be able to improve its discharge performance. The surface microscopy analysis results are in good agreement with those of the self-corrosion test and electrochemical characteristics.