Research on Cu-6.6%Al-3.2%Si Alloy by Dual Wire Arc Additive Manufacturing

In this work, the cold metal transfer (CMT) welding technique was used to additive manufacture Cu-6.6%Al-3.2%Si alloy. A dual wire feeding approach was adopted to separately feed SAFRA CuSi3 wire and AlSi5-ER4043 wire into the molten pool. To overcome the defect of non-uniform sample height, the CMT welding head was used in the round-trip configuration to deposit the samples. The deposited samples were characterized for their (1) microstructure and (2) mechanical properties of hardness and tensile strength. Microstructural characterization was done using optical microscopy (OM), scanning electron microscopy and transmission electron microscopy. From the elemental analysis, the central region of the deposited layer was enriched in aluminum and depleted in silicon compared to the region at the border of the layer. Evaluation of the mechanical properties showed that the deposited samples had good strength and ductility. The addition of silicon and manganese effectively improved the hardness and tensile strength properties of the deposited alloy.