Funding cycle 2017

To enable the use of AM in broad industrial practice, specific tools are required. Function-oriented active principles are a proven tool in the design process to find solutions. Within the project corresponding active principles are developed, especially for AM, and verified on demonstrators and applications. The potential of a function-orientated AM-design is illustrated and examined on industrial applications. In 2017, the focus was on the topics “heat transfer” and “structural optimization”.

Information about the mechanical properties are essential for designers in order to design products for application. Particularly for a dynamical application, like in the automotive industry or aircraft, the fatigue and creep behavior of the parts has to be known, so that the parts fulfill the calculated product life cycle. In this project, the fatigue behavior of Fused Deposition Modeling (FDM) components built with Ultem 9085 and Ultem 1010 is investigated. The dynamic properties of the material Ultem 9085 are tested at low and higher temperatures and Ultem 1010 is analyzed at higher temperatures. In further proceedings of the project, investigations on the deformation behavior of the materials at higher temperatures will follow.

The aim of this project is to reduce the high residual stresses and the shrinking of the material caused by the high cooling rate during the building process, which leads to crack formation. In this project, a heated building platform helped to reduce the temperature gradient, which leads to certain microstructural changes that made these materials processable with selective laser melting.

The availability of high performance LS materials is still limited to mainly polyamide 11 and polyamide 12 powder. However, these materials do not match to requirements of some advanced applications, for example in the electronics or automotive industry where higher material strengths and temperature resistance is required. The motivation of this project is to robustly process a new material – PA613, delivered by Evonik – and to specify its powder and resulting part properties. Since the material can be processed on regular “low temperature” LS systems like EOS P39x machines, PA613 material promises a great increase of application fields using already industrially established machine types.

Ti6Al4V is the most commonly used alloy, because of its well-balanced property profile.  Different heat treatments allow to tune microstructure and properties for different requirements and applications. During the use phase of powder, effects like out-washing of fine fractions, pick up of oxygen as well as enrichment of splashes change powder characteristics. In addition, there is a possibility of powder decomposition due to the powder handling process. Therefore, the powder quality permanently changes during the manufacturing process. Another point is the lot to lot variation of the powder quality inside the specified ranges. Scope of this project was to investigate the influence of relevant changes of powder characteristics on material as well as part properties.

The project addresses the fabrication and analysis of three challenging materials via selective laser melting (SLM).
Two medium carbo steels and a high carbon content CoCr-alloy are chosen in order to expand the material spectrum
available for SLM. During this one-year project, thorough parameter-studies will be conducted to determine suitable
parameter-sets. Additionally, preliminary microstructural and mechanical results will be obtained.