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Laser powder-bed fusion has become one of the most important techniques in additive manufacturing. For guaranteeing the possibility of manufacturing highly specialized and advanced components, currently intensive research is carried out in this field. One area of this research is the material-specific macroscopic anisotropy, which is investigated in our work by comprehensive static mechanical experiments. The material which was tested within this study was the precipitation-hardenable AlSi10Mg alloy, with the focus on installation space orientation. Tensile and compression tests were performed, the results for the Young's modulus in compressive loading exceeded the previously known values of this material in tensile loading and achieved values of up to 79.8 GPa. As a result of this investigation, a chemical spectroscopic analysis was undertaken and from the actual chemical composition, a relative density of 99.86% of the samples was determined.

The use of additive manufacturing in industry and research rises consistently. As new applications for this manufacturing method emerge, their implementation requires material optimization for additive manufacturing. Through the use of TiC and TiB2particle admixtures to different AlSi-alloys, possible improvements in density and moreover, static mechanical and high cycle fatigue properties were investigated. This allows a wider variety of components to be manufactured, as these AlSi-alloys with particle admixtures can endure higher loads in comparison to previously used AlSi-alloys. The different material compositions which were manufactured from mixed powders have undergone tensile and rotary bending fatigue tests. The porosity, the hardness and the particle distribution as indicators of the quality and applicability of the materials were determined and compared to pure AlSi-alloys. Within the scope of this study, an AlSi16 alloy with a particle admixture of µm-sized TiB2with a mass percentage of 12% achieved the best results, namely a yield and tensile strength of 299 MPa and 445 MPa, respectively, in addition to a Young´s modulus of 88.6 GPa. In comparison to other conventionally used materials, AlSi16 with micro TiB2admixtures showed noteworthy improvements.

Laser powder bed fusion has become one of the major techniques within metal additive manufacturing, especially when delicate structures and high geometric accuracy are concerned. Lately, the awareness of the material-specific macroscopic anisotropy has risen and led to widespread investigations on the static mechanical strength. However, little is known about the fracture behavior of the layer-wise fabricated metal components and their affinity of crack propagation between consecutive layers, which is particularly important for aluminium–silicon alloys containing embrittled zones in double-irradiated areas. A recent study indicated that there is a significant drop in fracture toughness in case the crack growth direction is parallel to the layering. To investigate this matter further and to shed light on the fracture toughness behavior in the range of a 0°–45° angle offset between the crack growth direction relative to the layering, notched samples with varying polar angles were subjected to mode I fracture toughness testing. Our results indicate that the fracture toughness is an almost-stable characteristic up to a mismatch of about 20° between the crack propagation path and the layering, at which point the fracture toughness decreases by up to 10%.