Metallic microparticles play an important role for additive manufacturing processes as well as for applications of functional materials. For the first one, they form the base material for additively building complex structures by local melting with a laser beam. For this process, it is crucial to know size, shape and defect distributions of particle ensembles[1,2], as well as the structure the packed particles form prior to melting in order to achieve homogeneous parts.
For the application of functional, e.g. magnetocaloric materials, packed structures of microparticles are typically used as a geometry. For this, in-depth knowledge of the internal structure of packed bed is indispensable. For magnetocaloric particles even the functional properties are affected by structural aspects, as magnetostatic coupling effects can occur between particles in close proximity. A combination of 3D structural information obtained by XCT with data of 2D methods like magneto-optical Kerr microscopy can expand the scope of these techniques by providing information in the “third dimension”, like e.g. the size and position of minority phases and defects hidden beneath the observed surface.
To summarize, we will show that non-destructive imaging with X-ray microtomography is a powerful tool both for the process optimization in additive manufacturing as well as for understanding structure-property relationships in functional materials.
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 T. Gustmann, A. Neves, U. Kuehn, et al., Influence of processing parameters on the fabrication of a Cu-Al-Ni-Mn shape-memory alloy by selective laser melting, Additive Manufacturing 11 (2016), S. 23-31 URL
 A. Funk, M. Zeilinger, A. Waske et al., MnFePSi-based magnetocaloric packed bed regenerators: Structural details probed by X-ray tomography, Chemical Engineering Science 175 (2018),
 A. Waske, B. Dutta, N. Teichert et al., Coupling phenomena in magnetocaloric materials, submitted to energy Technology 2018
 A. Funk, M. Zeilinger, A.Waske, et al., Hysteresis of MnFePSi Spherical Powder Ensembles Studied by Magneto-Optical Imaging, Physica Status Solidi B online first (2017), S. 1700345/1-7
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