The following projects are currently being worked on as part of our research focus "Additive Manufacturing":
AM-MikroMod - Acquisition of temperature gradients and local cooling rates in laser additive manufactured components to describe and modify microstructural properties
The aim of the cooperation between Fraunhofer IWM and Leibniz IWT is a modification of the microstructure of laser additively manufactured Ti6Al4V components based on the locally and time-dependent induced energy.
This will be done by a detailed description of the temperature history by means of in-situ high-speed infrared measurement and derived thermal modeling of a laser additively manufactured component. The temperatures and temperature gradients measured in the molten pool, its surroundings and the entire component will be used to derive process and scan strategies for specific local thermal loads, e.g. as a function of the component height, installation space, support strategy and layer thickness. This should allow targeted grading or homogenization of the material. The local cooling rate during laser additive manufacturing is a decisive factor for the microstructural properties of Ti6Al4V in terms of grain size and formation of certain phases. From an exact recording of the local heating and cooling rates as well as their correlation with the component microstructure and the mechanical properties, generic correlations are derived by means of simple artificial neural networks.
Processing: Leibniz-IWT Lightweight Materials, Fraunhofer IWM
Funding: BMWK- AiF/IGF (22102 N)
Duration: 01.02.2022 until 31.07.2024
This project is part of the research focus "Additive Manufacturing" at IWT Bremen.
Contact:
M. Sc. Mika Altmann
Phone: +49421 218 51414
E-Mail: altmann(at)iwt-bremen.de
LegoLas - In-situ alloy variation in powder bed based laser beam melting
The aim of the DFG research project is the exact production of variably alloyed samples by means of powder bed based laser beam melting.
The production of variably alloyed samples is to be realized by an approach developed at Leibniz-IWT, consisting of a process combination of suspension pressure technology and powder bed based laser beam melting. This process, which is to be automated, should be able to produce graded structures with specific lower-alloyed and higher-alloyed regions as required. The basis of these different alloy variants is always the same starting powder within a manufacturing process. Furthermore, the research project will examine in detail the distribution of the alloying element both in the component space as a result of the gas flow and in the remelted component volume. The aim is to achieve a broad understanding of the recyclability of the starting powder used, without possible impurities of the applied alloying element influencing subsequent processes.
This project is funded by the German Research Foundation.
Processing: WT-LW, BIAS GmbH
Funding: TO 1395/1-1
Duration: 01.07.2021 - 30.06.2024
This project is part of the research focus "Additive Manufacturing" at IWT Bremen.
Contact:
Dr.-Ing. Anastasiya Tönjes
Tel.: 0421 218 51491
E-Mail: toenjes(at)iwt-bremen.de
M.Sc. Marcel Hesselmann
Tel.: 0421 218 64549
E-Mail: hesselmann(at)iwt-bremen.de
UBRA Portal
The core of the project is the investigation and optimisation of the additive manufacturing process through automatic selection and adaptation of suitable parameter sets of the manufacturing process and the material selection through approximate and probalistic predictor functions.
Endoprosthetic implant fittings, such as hip and knee joints, contribute to a higher quality of life and represent an established procedure. The Ti6Al4V alloy is one of the materials used for this. This alloy has a high specific strength, stiffness, biocompatibility and corrosion resistance. In addition to forged or cast endoprostheses, these are now also manufactured with patient-specific geometries using laser additive manufacturing from the powder bed (Laser Powder Bed Fusion, LPBF). A certain amount of residual porosity in LPBF-produced objects is unavoidable. A distinction is made between gas porosity, bonding defects and keyhole porosity. Any type of porosity can lead to fatal failure, as it acts as a crack initiation point, especially under dynamic loading. LPBF objects are therefore subjected to hot isostatic pressing (HIP) for critical applications.
The core of the project is the investigation and optimisation of the additive manufacturing process through automatic selection and adaptation of suitable parameter sets of the manufacturing process and the material selection through approximate and probalistic predictor functions. To this end, machine-approximated prediction models will first be derived that allow the failure and service life of the components to be estimated on the basis of the process parameters and other sensory manufacturing data (forward model). With this knowledge, the inverse problem (backward model) should finally be obtained in order to be able to estimate the optimal manufacturing parameters from given result parameters of the products (properties).
This project is supported by the U Bremen Research Alliance with funding from the state of Bremen within the framework of the AI Center for Health Care.
Working on: Leibniz IWT-WT and University of Bremen
Funding: UBRA 2021
Contact:
M. Sc. Mika Altmann
Tel.: 0421-218 51414
E-Mail: altmann@iwt-bremen.de
TIRIKA - Technologies and repair processes for sustainable aviation in a circular economy
As a research partner in this joint project, Leibniz-IWT supports the goal of environmentally friendly aviation.
The research focuses on increasing the degree of lightweight construction, the use of materials for new propulsion technologies and increasing the service life of highly relevant components. In this context, research is being conducted on improving the mechanical properties of laser-additively manufactured Ti6Al4V components. Novel heat treatment processes are to be developed that exploit the mechanical potential of laser-additive manufactured components while taking into account their special microstructure.
Processing: WT-LW, joint project under the direction of Airbus Operations GmbH.
Funding: LuFo VI-2 20W2103J
Duration: 01.01.2022 until 31.03.2025
Contact:
M.Sc. Mika León Altmann
Tel: +49 421 218 51414
E-Mail: altmann(at)iwt-bremen.de