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 knowledge of thermal conductivity is essential for improving and designing tools for hot working applications like hot stamping and high‐pressure aluminum die casting. This study investigates the influence of alloying composition and heat treatment on thermal conductivity of two different hot work tool steels in the temperature range between 20 and 500 °C. Thermal conductivity was determined with an indirect measurement by using the dynamic method. The thermal conductivity of the two tool steels was found to be dependent on the amount of alloying elements, heat treatment condition, and operating temperature. In the regime of hot stamping applications, i.e for service temperatures below 200 °C, thermal conductivity increases with temperature for both steels irrespective of their heat treatment condition. In applications in which tools are subjected to temperatures above 200 °C (such as high‐pressure die casting operations), thermal conductivity of the steels decreases as tool temperature increases.

Laser powder-bed fusion (LPBF) has significantly gained in importance and has become one of the major fabrication techniques within metal additive manufacturing. The fast cooling rates achieved in LPBF due to a relatively small melt pool on a much larger component or substrate, acting as heat sink, result in fine-grained microstructures and high oversaturation of alloying elements in the α-aluminum. Al–Si–Mg alloys thus can be effectively precipitation hardened. Moreover, the solidified material undergoes an intrinsic heat treatment, whilst the layers above are irradiated and the elevated temperature in the built chamber starts the clustering process of alloying elements directly after a scan track is fabricated. These silicon–magnesium clusters were observed with atom probe tomography in as-built samples. Similar beneficial clustering behavior at higher temperatures is known from the direct-aging approach in cast samples, whereby the artificial aging is performed immediately after solution annealing and quenching. Transferring this approach to LPBF samples as a possible post-heat treatment revealed that even after direct aging, the outstanding hardness of the as-built condition could, at best, be met, but for most instances it was significantly lower. Our investigations showed that LPBF Al–Si–Mg exhibited a high dependency on the quenching rate, which is significantly more pronounced than in cast reference samples, requiring two to three times higher quenching rate after solution annealing to yield similar hardness results. This suggests that due to the finer microstructure and the shorter diffusion path in Al–Si–Mg fabricated by LPBF, it is more challenging to achieve a metastable oversaturation necessary for precipitation hardening. This may be especially problematic in larger components.

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The mechanical and microstructural properties of aluminum A356 cast alloy are investigated as a function of hot isostatic pressing and heat treatment parameters. The combined hot isostatic pressing and heat treatment process leads to an improvement of mechanical properties when compared to regular hot isostatic pressing with no separate heat treatment. An oversaturated state with magnesium and silicon atoms dissolved in the aluminum matrix can be achieved by increasing the quenching rate to 6.9 K/s within the temperature range between 813 K and 473 K. Aging can be performed directly after hot isostatic pressing, without the necessity of a separate solution annealing step. Thereby, the overall processing costs could be reduced.