Additive manufacturing is especially suitable for complex-shaped 3D parts with integrated and optimized functionality realized by filigree geometries. Such designs benefit from low safety factors in mechanical layout. This demands ductile materials that reduce stress peaks by predictable plastic deformation instead of failure. Al–Cu wrought alloys are established materials meeting this requirement. Additionally, they provide high specific strengths. As the designation “Wrought Alloys” implies, they are intended for manufacturing by hot or cold working. When cast or welded, they are prone to solidification cracks. Al–Si fillers can alleviate this, but impair ductility. Being closely related to welding, Laser Beam Melting in Powder Bed (LBM) of Al–Cu wrought alloys like EN AW-2219 can be considered challenging. In LBM of aluminium alloys, only easily-weldable Al–Si casting alloys have succeeded commercially today. This article discusses the influences of boundary conditions during LBM of EN AW-2219 on sample porosity and tensile test results, supported by metallographic microsections and fractography. Load direction was varied relative to LBM build-up direction. T6 heat treatment was applied to half of the samples. Pronounced anisotropy was observed. Remarkably, elongation at break of T6 specimens loaded along the build-up direction exceeded the values from literature for conventionally manufactured EN AW-2219 by a factor of two.

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A laser welding process using a 30-kW fiber laser with scanning mode optics is investigated in the paper. Welding is conducted in two ways: constant laser beam trajectory and wobbling trajectory with the use of lower speed and power. The main goal was to investigate the influence of the second wobbling laser welding pass on microstructure and mechanical properties of structural steel. The following parameters were monitored: visual control and mechanical properties (microhardness, three-point bend, and Charpy impact Vnotch test); metallographic analysis and 2D and 3D computer tomography (CT) were also done. The results show that after the second welding pass, with wobbling trajectory of laser beam, middle and cap parts of the seam have a lower microhardness, in relation to the root part. It can be explained by annealing influence of the second wobbling pass at weld metal.

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