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For additive manufacturing of metals, selective laser melting can be employed. The microstructure evolution is directly influenced by processing parameters. Employing a high energy laser system, samples made from austenitic stainless steel were manufactured. The microstructure obtained is characterized by an extremely high degree of anisotropy featuring coarse elongated grains and a h001i texture alongside the build direction during processing. Eventually, the anisotropy of the microstructure drastically affects the monotonic properties of the current material. Recently, techniques allowing for additive manufacturing of highly complex components have been gaining significant attention in both industry and academic research. [1][2][3] As no tools are required for processing, small to medium batches can be produced very efficiently. Polymers and metals can be processed depending on the technique employed; for processing of metals, wire-based techniques are available, but techniques employing a powder bed have the higher impact. Electron beam melting and selective laser melting (SLM Ò ), both melting the powder locally accordingly to data provided by a model stemming from computer-aided design, are widely used nowadays. [1][2][3] From the academic point of view, the high degree of design freedom allowing for an extreme lightweight design and the aspect of microstructural design are very attractive. [4,5] The latter aspect is mainly influenced by process-related parameters such as scanning strategy and energy input. As has been shown by Thijs et al. for an aluminum alloy processed by selective laser melting in a very recent paper, the thermal gradient during cooling and the direction of heat flow are key parameters for microstructure evolution and design, respectively.[4] Numerous metals and alloys have been processed by SLM Ò ; aluminum and titanium alloys, nickel-based alloys, and stainless steels have been the subjects of recent work. [1][2][3][4][5][6][7][8] Focusing on materials such as nickel-based alloys and austenitic steels, high-temperature applications are of interest. For such applications, a coarse-grained anisotropic microstructure is highly attractive.[9] The current paper addresses this topic and introduces a highly anisotropic austenitic alloy 316L directly obtained from powder processed by SLM Ò . The conditions for obtaining such kind of microstructure are discussed in light of the processing parameters.The material employed in the current study was facecentered cubic (fcc) 316L stainless steel. The initial powder with a mean particle size of 40 lm was supplied by SLM Solutions GmbH. For fabrication of cubical and tension specimens, a SLM Ò -280 HL selective laser melting system in combination with MTT AutoFab software (Marcam Engineering GmbH) was used. The tensile specimens were built in the z-direction; thus, the loading axis was parallel to the built direction. Two Yttrium fiber lasers are employed in the current SLM Ò system, featuring maximum beam energies of 400 W and 1000 W, respectively. ...

A B S T R A C T In many practical cases, the crack growth leads to abrupt failure of components and structures. For reasons of a reliable quantification of the endangerment due to sudden fracture of a component, therefore, it is of enormous importance to know the threshold values, the crack paths and the growth rates for the fatigue crack growth as well as the limiting values for the beginning of unstable crack growth (fracture toughness). This contribution deals with the complex problem of a-however initiated-crack, that is subjected to a mixed-mode loading. It will present the hypotheses and concepts, which describe the superposition of Mode I and Mode II (plane mixed mode) as well as the superposition of all three modes (Mode I, II and III) for spatial loading conditions. Those concepts admit a quantitative appraisal of such crack situations and a characterization of possible crack paths.

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