Wire-Arc Additive Manufacturing of Aluminum Alloy Components: Impact of the Heat Input on the Mechanical Properties

Wire and arc additive manufacturing (WAAM) was developed as an efficient technique based on the layer-by-layer build-up approach. WAAM presents a powerful production process offering low-cost manufacturing of complex components used in different industrial applications. Process parameters such as energy input generate a specific structure thermal history of the built structure and thus affect the resulting components properties. In this work, two 5356 aluminum alloy components were build-up by WAAM using different heat input and then machined along the horizontal and vertical directions. Tensile tests were used for the mechanical characterization. The results reveal that for the component manufactured with lower heat input, the mechanical properties (tensile strength and elongation) of vertical samples are lower than those of the horizontal ones. The tensile fracture analysis of the tested samples highlights structural defects namely a lack of cohesion at some regions, which may be one of the causes of anisotropic mechanical properties. The adopted strategy using higher heat input for 5356-Al enhance the resulting internal structure and consequently improve the mechanical properties.