The department of Metallic Materials of the Institute of Materials Engineering at the University of Kassel focuses on process-microstructure-property-damage relationships in conventionally and additively processed metallic materials. Generally, the research interests can be departed into four main groups. Besides Additive Manufacturing (AM) and Shape Memory Alloys (SMA), the activities in the department focus on residual stresses as well as fatigue and damage.
In case of AM, powder bed processes (PBF-LB/M and PBF-EB/M) as well as laser metal deposition / direct metal deposition (LMD/DED/DMD) are used to realise microstructurally and functionally graded components. Research activities include the realisation and in-depth characterization of filigree lattice structures. In-situ characterization techniques are widely employed to assess microstructure-property relationships on the local scale. A special emphasis is on the development of novel alloys for AM. Based on a profound knowledge of the open challenges in AM, i.e. porosity, anisotropy, residual stress, chemical heterogeneity, surface roughness, limited damage tolerance, etc., new alloy designs are proposed and assessed to overcome such issues. So far, the focus was on metallic alloys for structural applications, e.g. Ti-6Al-4V, aluminium alloys, stainless steels, and Ni-based superalloys, however, within the last few years also numerous SMAs processed by AM were investigated.
The department of Metallic Materials has access to numerous advanced characterisation methods. Lab-based experiments including mechanical tests (under quasi-static and cyclic loading), optical microscopy, high-resolution electron microscopy, transmission electron microscopy, computed tomography (CT), X-ray diffraction (texture, phase fractions and residual stress) as well as mechanical residual stress measurements by means of the hole drilling method are further supported by in-situ experiments based on Neutron- and Synchrotron-diffraction. Not only the use of well-established approaches is considered, but also new and efficient approaches, e.g. for screening of material properties are elaborated and assessed.