Additive manufacturing methods for industry and medicine
Components need to become ever lighter, more resilient and functionally more versatile in order to meet increasing technical demands. The additive manufacturing of hybrid, porous components is a promising approach for achieving significant progress in areas such as medical technology and aviation.
Hybrid components combine different materials that are specifically used at different positions in the workpiece in order to optimally fulfil specific requirements such as strength, flexibility or thermal conductivity.
Through the targeted integration of porosity into the component, the material requirement can be reduced without significantly impairing the mechanical strength. This lightweight construction method is particularly useful where low weight combined with high stability is crucial.
Collaborative research centre for the production of hybrid, porous components
The combination of hybridity and porosity unites the advantages of both properties and opens up new possibilities for functional integration in a component.
This is why the production of hybrid, porous components is now being researched for the first time – as part of the new Collaborative Research Centre/Transregio ‘Multifunctional high-performance components made of hybrid porous materials’ at the University of Kaiserslautern-Landau (RPTU) and Leibniz University Hannover.
In a sub-project, which is being carried out jointly with the Chair of Computational Physics in Engineering (CPE) at RPTU, the Institute of Production Engineering and Machine Tools (IFW) is developing simulation methods to predict the properties of these components resulting from the manufacturing process.
Process simulation: the key to efficiency
Process simulation is necessary in order to predict the end result as early as the planning phase and thus enable a well-founded process design. Laser directed energy deposition (L-DED), an additive manufacturing process in which a laser beam melts the material in powder or wire form and applies it layer by layer, is being investigated. By varying process variables, the aim is to achieve precise control of the material properties so that the deposited areas fulfil the requirements.
The decisive advantage of the new simulation methods over previous methods lies in the mapping of spatial and temporal changes in component properties. As a result, physical and mechanical properties such as temperature development during processing and the distribution of residual stress in the component can be predicted. This makes it possible to adapt the manufacturing process so that it fulfils the high quality and efficiency requirements. At the same time, the flexibility to combine different materials and porosity in a single component is guaranteed.
The simulation allows the properties of the components to be predicted so that time-consuming test phases on physical prototypes can be dispensed with. This makes it possible to integrate the right parameters directly into the production process, which shortens production times and enables products to be brought to market more quickly in the long term.
Challenges of process simulation
The production of hybrid, porous components requires innovative approaches. The focus here is on three central challenges:
Complexity of the processes
The production of hybrid, porous components requires all relevant aspects of the manufacturing process to be taken into account. This includes the microscopic interactions during melting, the temperature and residual stress distribution within the component as well as the mechanical and thermal properties of the finished component. This holistic approach is necessary in order to produce components that are not only light and stable, but also optimised for the respective application conditions.
Demand for computing resources
The development of precise simulation models and suitable manufacturing processes requires high computing capacities. The detailed analysis of large components is particularly resource-intensive. The development of efficient algorithms and methods that reduce memory requirements and computing power is therefore of central importance. This is necessary in order to make the simulation of hybrid, porous components economical, even on a large scale.
Lack of manufacturing processes and simulation methods
The combination of different materials and the targeted integration of pore structures place special demands on simulation and production technology. There is currently a lack of suitable simulation methods that can map the complex interactions in hybrid, porous components. As part of the project, specific prediction models and processes are being developed in order to design the production of such components efficiently and reliably.
Long-term goals of production technology
Despite the current challenges, such as the complexity of the processes and the high demand for computing resources, the project aims to achieve significant progress in manufacturing technology in the coming years. The development of a comprehensive simulation environment that integrates all important aspects of the manufacturing process will make it possible to plan the production of hybrid, porous components with new functionalities more efficiently.
In future, it should not only be possible to precisely adjust materials and mechanical properties, but also to integrate sensors and actuators directly into the components. In addition, the targeted control of magnetic properties will be a key component of further development. These technological advances will extend the service life of the components, increase their performance and at the same time make production more sustainable and cost-efficient.