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Before utilising selective laser melting in real applications, the process as well as the outcome component and its characteristics need to be fully understood. Based on the layer-wise fabrication, with its distinctive orientations in translations and thermal influences within this additive manufacturing process, the obtained material properties and the microstructure are anticipated to be anisotropic. The selective laser melting process involves: the laser movement pattern in plane and rotation between single layers; recoater movement; substrate plate heating and movement; laser irradiation from the top; and inert gas flow. In order to gain insight into the process and its related characteristics, different sets of prismatic specimens in terms of orientation and inclination were produced and evaluated. The evaluation contained surface quality investigations with two independent measurement approaches, i.e. tactile and optical, density measurements based on the Archimedes principle and micro-section evaluation. Furthermore, ultrasonic analyses were conducted to study the feasibility of determining the mechanical properties, i.e. Young's modulus and Poisson's ratio, in accordance with the recorded longitudinal and transversal sonic velocities.The chosen raw material for these investigations was AlSi10Mg and the fabricated parts exhibited a high relative density of at least 99.5 %. Remarkable deviations were evident in the obtained surface quality and clear trends could be determined based on the inclination and orientation condition of the sample during manufacturing. In regards to the ultrasonic investigation, it was found that the reported inherent anisotropy of selective laser melted samples could not be detected with the non-destructive ultrasonic investigation, and destructive procedures, to date, represent the only reliable method to accurately reveal the material characteristics.Keywords: Powder-bed based additive manufacturing / Flushing process / irradiation strategy / Positioning and inclination / Surface quality Im Rahmen der erfolgreichen Implementierung des selektiven Laserstrahlschmelzens in industriellen Anwendungen sind die Kenntnis und das Verständnis der charakteristischen und verfahrensbezogenen Eigenschaften der generierten Kompo-

Customers nowadays regard the noise and vibration behavior as an essential product property. Cellular character materials, in particular hollow sphere structures, are predestined to absorb sound in a very efficient manner due to their cellular character. Depending on the constituent material, the geometric parameters like the diameter of the spheres, the thickness of the walls and the assembling schema of single spheres, the absorption coefficient can be reduced to very low levels. In contrast to other cellular materials, the frequency and bandwidth can actively be influenced by the variation of the above mentioned parameters. In order to predict the acoustic behavior of a structure, FE or CFD analyses are used as standard tools. In addition, there exist some parameter based models, e.g. the BIOT theory, which characterizes the absorption, transmission and reflection coefficients using a few macroscopic parameters. Within this contribution, the acoustic properties of hollow sphere structures are investigated by a so‐called virtual material laboratory GeoDict (by Math2Market GmbH, originally by the Fraunhofer Institute for Industrial Mathematics). The results for the absorption and reflection coefficients are compared to those gained by classical analysis methods and experiments based on Kundt's tube.

Metallic hollow sphere structures (MHSS) combine the well-known advantages of cellular metals with the excellent material properties of solid base metals. The basic cell is a hollow sphere. Metallic hollow sphere structures can be assembled by sintering, soldering, or adhesive bonding. The macroscopic thermal property and, more specifically, the thermal conductivity is an essential material property. The objective of this work is to address the thermal conductivity of MHSS in dependence of the geometrical parameters of a single sphere and the ordering scheme of the assembled structure with a special focus on isotropy and anisotropy. From a macroscopic point of view, which is often used within the engineering design process, the characterization of the properties of MHSS demand an approximative description coming out of a homogenization. Within this paper the unit cell approach is used. The numerical analysis is done on the basis of a parameterized 3D-CAD model enabling the variation of the sphere size and wall thickness as well as the geometry of the interconnection between spheres. Periodic boundary conditions are applied. Results for the macroscopic thermal conductivity are presented for regular-packed (CP, BCC, FCC, and HCP) as well as randomly packed unit cells representing sintered or soldered MHSS. The anisotropy is discussed by the 3 Â 3 thermal conductivity tensor.

The innovative core of this paper is the development, simulation and experimental validation of a modular tool set for the production of different window contour types made of wood. Caused by the modular structure and the high rotational speed in wood machining, an essential objective in the development of a modular tool set is to achieve close customer defined tolerances. This can only be achieved with a good balancing grade. To determine the unbalance, a parametric 3D-CAD-model of the validation model is imported into a Multi Body Simulation (MBS) software and analyzed numerically. The results of these simulations are then validated by experimental analysis on a balancing machine.