Mechanical properties of 2219-Al components produced by additive manufacturing with TIG

Several 2219-Al components were produced by additive manufacturing with tungsten inert gas (TIG), and thin walls were selected to study the mechanical properties. Results show that the average hardness is 77.5 HV0.2, and the deposited materials are not sensitive to post heat during manufacturing process. No significant difference of hardness can be defined between strips and inner layers. Tensile tests were performed on welding and building directions. The average ultimate strength is 237 MPa, which is only 57 % of the property of 2219-T6 (routinely used state). Analysis suggests that the insufficiency of tensile strength can be ascribed to the absence of precipitation strengthening effect during the manufacturing process. The material exhibits an isotropic feature in tensile properties. Fracture observation shows that theta phases are the initiations of cracks. The effect of decreasing loading areas, due to the strip-like distributing porosities, is insignificant in welding direction. However, in building direction, it influences the crack propagating path.