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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
    Modular Digital Production Twin as Enabler for Sustainable Value Creation
    Climate change and progressing urbanization urge to increase sustainability in all areas – not only, but especially in manufacturing. Digitization and particularly digital twins enable a more efficient, decentralized, and small-scale production. This helps companies to reduce the usage of natural resources and the overall environmental impact. Corresponding modular digital twins represent one configuration and must be configured specifically according to individual production orders. The determination of required type, amount and linkage of integrated data and partial models of the production processes and plants is complex. However, this determination is required to choose suitable tools for the digital factory and to adapt processes accordingly. The objective of this paper is to provide a concept for a modular digital production twin with integrated partial models as enabler for sustainable value creation. The concept will be concretized by means of requirements from an urban environment.
  • Publication
    Reuse of Smoulder in Laser Powder-Bed Fusion of AlSi10Mg - Powder Characterization and Sample Analysis
    ( 2024)
    Maurer, Oliver
    ;
    Jacob, Heiko
    ;
    Bähre, Dirk
    Metal additive manufacturing technologies, such as Laser Powder-Bed Fusion, often rate as sustainable due to their high material efficiency. However, there are several drawbacks that reduce the overall sustainability and offer potential for improvement. One such drawback is waste emerging from the process. These smoulder particles form when the laser hits the powder-bed surface, are blown away from the part by the shielding gas stream and accumulate on the edge of the build chamber. Usually, smoulder does not contribute to the circular reuse of powder that was part of the powder-bed but was not integrated into a part. Instead, it marks an end-of-life state of powder. Significant amounts of smoulder accumulate depending on the irradiated area or the build volume in one job, respectively. This results in the waste of powder that was produced with low energy efficiency. This study investigates the question of whether smoulder can transform from waste to resource via common powder characterization methods and first build jobs using processed smoulder. The investigation of process-relevant powder properties like apparent density and flowability showed no significant difference between virgin powder and smoulder. Sample characterization indicated that neither porosity, surface quality nor mechanical properties deteriorate when samples contain about 50% smoulder. This allows for the reuse of smoulder in terms of powder characterization and part quality.
  • Journal
  • Publication
    Großer Schutz für Kleine
    Mit dem Small-Business-Paket will Enginsight mit seinem gleichnamigen Sicherheitswerkzeug auch sehr kleine Unternehmen in die Lage versetzen, ihr Schwachstellenmanagement und Monitoring auf eine effiziente und kostengünstige Weise zu stärken.

Most viewed

  • Publication
    Directing nitrogen-doped carbon support chemistry for improved aqueous phase hydrogenation catalysis
    ( 2020) ;
    Rustam, Lina
    ;
    Thomann, Ralf
    ;
    Melke, Julia
    ;
    Fischer, Anna
    ;
    White, Robin J.
    Selective hydrogenations in the aqueous phase are an important transformation in the context of developing biorefinery concepts. In this report the application and optimisation of nitrogen-doped carbon (NDC) supported Pd nanoparticles as hydrogenation catalysts is discussed in the context of directing support (e.g. N) chemistry for improved catalytic performance in the aqueous phase. As a demonstrative example, the aqueous phase hydrogenation of phenol to cyclohexanone (e.g. a platform for polyamide production) is utilised. Catalyst supports were prepared based on an initial hydrothermal synthesis to yield NDC xerogels (from biomass precursors), the chemistry of which (e.g. functionality) was directed using a secondary thermal carbonisation (Tc) step at different temperatures (i.e. 350, 550, 750, 900 and 1000 °C). After Pd introduction, it was found that size, dispersion and electronic structure of the formed nanoparticles is affected by the surface chemistry of the NDC. This consequently led to higher turn-over frequency (TOF) and stability of the prepared catalysts compared to a ""nitrogen-free"" carbon supported Pd and a commercial, carbon supported Pd (Pd/AC) catalyst. Pd/NDC 900 (featuring predominantly quaternary and pyridinic N) catalysed the complete conversion of phenol at 99% selectivity to cyclohexanone, with excellent stability over 11 recycles and no discernible catalyst sintering or leaching (in contrast to the commercial catalyst). High catalytic stability, activity and selectivity make the Pd/NDC 900 catalyst highly applicable for aqueous phase hydrogenation reactions, whilst the general principle opens scope for support tailoring for application (e.g. biorefinery hydrogenations) and the development of structure/activity relationships.
  • Publication
    Laser pulse energy conversion on sequence-specifically bound metal nanoparticles and its application for DNA manipulation
    ( 2005)
    Garwe, F.
    ;
    Czaki, A.
    ;
    Maubach, G.
    ;
    Steinbrück, A.
    ;
    Weise, A.
    ;
    König, K.
  • Publication
    Measurement of Local Recombination Activity in High Diffusion Length Semiconductors
    We present a conceptual approach for the localisation and characterisation of local sites of recombination in high diffusion length semiconductors under photovoltaic field conditions. While established imaging techniques operate in this very regime of uniform "1 sun" illumination, inevitable lateral diffusion of charge carriers veils the origin and severity of localised recombination sites. To reduce this limitation due to lateral diffusion the natural choice is using focussed charge carrier excitation and detection in combination with scanning the specimen. The resulting photoluminescence intensity maps are of high spatial resolution and may be composed of a superposition of a multitude of recombination active defects influencing each other due to the high bulk diffusion length. We demonstrate the feasibility of a self-consistent calibration of the setup quantum efficiency in such experimental condition which delivers a charge carrier density map in absolute units. A solution is presented to disentangle the superposition of local sites of recombination to isolate the actual recombination activity of every site. We demonstrate the feasibility of the approach experimentally on the high diffusion length semiconductor silicon.