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267829

Research outputs

As an application-oriented research organisation, Fraunhofer aims to conduct highly innovative and solution-oriented research - for the benefit of society and to strengthen the German and European economy.

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Projects

Fraunhofer is tackling the current challenges facing industry head on. By pooling their expertise and involving industrial partners at an early stage, the Fraunhofer Institutes involved in the projects aim to turn original scientific ideas into marketable products as quickly as possible.

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Researchers

Scientific achievement and practical relevance are not opposites - at Fraunhofer they are mutually dependent. Thanks to the close organisational links between Fraunhofer Institutes and universities, science at Fraunhofer is conducted at an internationally first-class level.

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Institutes

The Fraunhofer-Gesellschaft is the leading organisation for applied research in Europe. Institutes and research facilities work under its umbrella at various locations throughout Germany.

Recent Additions

  • Publication
    Berücksichtigung des Constraint-Effekts bei der Versagenbewertung duktiler Werkstoffe
    (DVM, 2024) ;
    Sguaizer, Yves
    ;
    El Khatib, Omar
    ;
    Hütter, Geralf
    ;
    Kiefer, Björn
    ;
    Christian, Amann
    Es werden experimentelle und numerische Untersuchungen zum Rissverhalten in zwei duktilen metallischen Werkstoffen unter Variation der Dehnungsbehinderung (Constraint) und damit der Spannungsmehrachsigkeit an der Rissspitze vorgestellt. Die experimentell ermittelten J-R-Kurven sowie der technische Initiierungskennwert J0.2 werden in Abhängigkeit von verschiedenen Constraint-Parametern, dem elastischen T-Stress, dem Q-Faktor sowie dem Spannungsmehrachsigkeitsgrad h, ausgewertet und durch einfache Korrelationsbeziehungen beschrieben. Des Weiteren wird gezeigt, dass die duktile Rissinitiierung und das anschließende stabile Risswachstum mit einem nichtlokalen schädigungsmechanischen Modell hinreichend gut beschrieben werden können. Am Beispiel eines rissbehafteten Bauteils wird die Anwendung der abgeleiteten analytischen Korrelationen zur Bewertung der Rissinitiierung aufgezeigt und mit schädigungsmechanischen Simulationen validiert.
  • Publication
    Determining the Efficiency of Mitigations Based on Covered Threats
    Prioritization of threats is an important skill for experts working in the cybersecurity field. With daily new discovered threats and a variety of tools providing information, warnings, and alerts, it is essential for experts working in cybersecurity to identify the most important warnings and threats and handle them efficiently to stay ahead of the growing competence, organization, and size of threat groups. To assist cybersecurity experts with these tasks, this paper provides an approach covering six steps that can be used to determine the efficiency of mitigations for a system under consideration. To this end, this paper describes a straightforward approach and provides an example in which it has already been used.
  • Publication
    Predicting the fiber orientation of injection molded components and the geometry influence with neural networks
    ( 2024)
    Herrmann, Till
    ;
    ;
    Salimova, Diyora
    ;
    The injection molding simulation of short fiber reinforced plastics (SFRP) is time consuming. However, until now it is necessary for predicting the local fiber orientation, to optimize the molding process and to predict the mechanical behavior of the material. This research presents the capabilities of artificial neural networks (NN) in predicting fiber orientation tensor (FOT) during injection molding processes, with a focus on enhancing computational efficiency compared to traditional simulation methods. Three NN architectures are compared based on simulated injection molded plates, with the goal of predicting the effect of the plate geometry on the local fiber orientation. Results indicate that NN outperform the baseline assumption of aligned fibers and demonstrate significant potential for accurate FOT prediction. The computational efficiency of NN, especially during the prediction phase, showcases a reduction in processing time by a factor of 104 compared to traditional simulation methods. This research lays a foundation for further exploration into the feasibility of NN in partly replacing time-consuming simulations for practical applications in injection molding processes.
  • Publication
    Accurate distances measures and machine learning of the texture-property relation for crystallographic textures represented by one-point statistics
    ( 2024)
    Iraki, Tarek
    ;
    ;
    Link, Norbert
    ;
    Sandfeld, Stefan
    ;
    The crystallographic texture of metallic materials is a key microstructural feature that is responsible for the anisotropic behavior, e.g. important in forming operations. In materials science, crystallographic texture is commonly described by the orientation distribution function, which is defined as the probability density function of the orientations of the monocrystal grains conforming a polycrystalline material. For representing the orientation distribution function, there are several approaches such as using generalized spherical harmonics, orientation histograms, and pole figure images. Measuring distances between crystallographic textures is essential for any task that requires assessing texture similarities, e.g. to guide forming processes. Therefore, we introduce novel distance measures based on (i) the Earth Movers Distance that takes into account local distance information encoded in histogram-based texture representations and (ii) a distance measure based on pole figure images. For this purpose, we evaluate and compare existing distance measures for selected use-cases. The present study gives insights into advantages and drawbacks of using certain texture representations and distance measures with emphasis on applications in materials design and optimal process control.

Most viewed

  • Publication
    OpenConfig Control of 100G/400G Filterless Metro Networks with configurable Modulation Format and FEC
    ( 2019)
    Paolucci, F.
    ;
    Sgambelluri, A.
    ;
    Emmerich, R.
    ;
    Giorgetti, A.
    ;
    Castoldi, P.
    ;
    Schubert, C.
    ;
    Fischer, J.K.
    ;
    Cugini, F.
    OpenConfig YANG extensions are proposed to enable dynamic selection of transmission parameters of 100G/400G transmitters with coherent reception in a filterless metro network. Data and control plane experimental validations exploiting the ONOS controller are provided.
  • Organizational Unit
  • Publication
    Estimating fibre direction distributions of reinforced composites from tomographic images
    ( 2016)
    Wirjadi, O.
    ;
    Schladitz, K.
    ;
    Easwaran, P.
    ;
    Ohser, J.
    Fibre reinforced composites constitute a relevant class of materials used chiefly in lightweight constructions for example in fuselages or car bodies. The spatial arrangement of the fibres and in particular their direction distribution have huge impact on macroscopic properties and, thus, its determination is an important topic of material characterisation. The fibre direction distribution is defined on the unit sphere, and it is therefore preferable to work with fully three-dimensional images of the microstructure as obtained, e.g., by computed micro-tomography. A number of recent image analysis algorithms exploit local grey value variations to estimate a preferred direction in each fibre point. Averaging these local results leads estimates of the volume-weighted fibre direction distribution. We show how the thus derived fibre direction distribution is related to quantities commonly used in engineering applications. Furthermore, we discuss four algorithms for local orientation analysis, namely those based on the response of anisotropic Gaussian filters, moments and axes of inertia derived from directed distance transforms, the structure tensor, or the Hessian matrix. Finally, the feasibility of these algorithms is demonstrated for application examples and some advantages and disadvantages of the underlying methods are pointed out.