Effect of Process Parameters on Mechanical Properties of Wire and Arc Additive-Manufactured AlCu6Mn

y Wire and arc additive manufacturing (WAAM) is an additive manufacturing technique that can directly fabricate large three-dimensional parts. A variable-polarity cold metal transfer pulse arc was employed to melt metal wire onto a substrate. Tensile tests and microscopy were conducted to investigate the effects of the heat input on the mechanical properties and microstructure of the AlCu6Mn after WAAM deposition. The highest tensile strength of 295MPa and tensile elongation of 18% were obtained with appropriate heat input. Also, the bottom region of the sample exhibited the best mechanical properties, followed by the middle and top region under the same parameters. This is mainly due to the increase of overburn defects and grain size in the top region with heat accumulation in the repeated thermal cycle.