Fused Deposition Modeling with metal powder filled filaments

The processing of metal powder filled polymer filaments in Fused Deposition Modeling (FDM) presents a comparatively new technology for the production of metal components. This technology enables powder-free handling of the base material and processing on low-cost FDM equipment. The aim of the research in cooperation with DMRC industrial consortium is to achieve a better understanding of the technology throughout the entire process chain. In addition to the general evaluation of the resulting component properties, the development of user guidelines is also at focus. These will be used to reduce the iteration steps from the first steps using the filament to a high-quality metal component. For this purpose, test specimens as well as methods are developed to show and evaluate the influencing variables on the manufacturing process.

As a basis for establishing processing guidelines, the process parameters and in particular the volumetric polymer discharge must first be controlled. For this purpose, both the areas of stationary and non-stationary strand deposition are considered. This enables the technology-specific design and processing limitations to be investigated. These limitations include the minimum manufacturable overhang angle, the maximum manufacturable hole diameter and the minimum manufacturable wall thickness. In order to demonstrate the specific design limitations, all geometries are manufactured without the use of a suitable support material. The results are evaluated both after FDM fabrication and after the debindering and sintering process. Important variables are the evaluation of warpage or distorsion and defects in gerneral occuring in the components.

The specific optimization of the process parameters as well as the development of the user guidelines lead to a better understanding of the processing of metal powder filled polymer filaments in FDM. This results in user-oriented support for the realization of desired metal component geometries.