Additive manufactured lightweight structures for civil aircraft components (KOBFS)

The Selective Laser Melting (SLM) process provides huge advantages for aircraft components like valve blocks and structural parts. In this project funded by the BMWi – “Federal Ministry for Economic Affairs and Energy”, the benefits of substituting conventionally manufactured parts by additively manufactured parts will be examined and quantified. The scopes are reducing costs, weight and time in comparison to the traditional design and the conventional manufacturing method.

Objectives
The aim is to develop a decision support scheme for future applications during the product engineering process and to elaborate the fundamentals for an Additive Manufacturing material database based on lightweight and composite structures, besides solid material properties. Moreover, investigations working on improving the process through topology optimization, which includes increasing the building speed of the SLM process and to develop fast and stable process routes that can be used for serial production, will be acquired. The intention is to reduce the processing time in every stage of the process chain, particularly in the Additive Manufacturing process.

Procedure
The project is divided into two work packages, the first work package works on identifying promising aircraft components and to adapt a trade-off methodology to rank these parts. According to this trade-off methodology, a decision scheme for future decisions will be developed with a complete description of process chain mapping possibilities and influencing factors for the process.

The second work package works on the development of lightweight structures and composite structures and their mechanical properties for several target functions. Moreover, the mechanical properties of solid material built with various adjusted parameter sets will be determined. The gained knowledge of the previous working steps will be merged in topology-optimized components to demonstrate the possibilities of Additive Manufacturing as a key technology of the future.

Latest results
Since the project started in January 2016, the fundamentals for the different working steps are finalized. The material database is discussed and the programming of a trade-off methodology tool has started. Furthermore, the initial steps for the determination of mechanical properties of the structures to be examined were done.

A knowledge base of the behavior of lattice, composite, support structures, and the influence of the part position on the building plate has been established. In addition to that, powder ageing effects in different build jobs with the same powder were analyzed. Investigations on adapting the default process route and for increasing the building speed through parameter optimization has been done. The results are shown in figure 2.

Outlook
The next working steps are further investigations on the topics mentioned above. The whole project is an iterative process and the gained knowledge during the project will be used for topology optimized parts. Moreover, addi-tional and extensive investigations on increasing the building speed while at least holding the properties and on combining different materials in composite structures will be examined finally.