terfaces between the individual phases or alloys and narrow heat affected zones resulting in limited the first-order residual stress, macroscopic distortion and secondary phase formation represents still a serious technological challenge [11]. By their principle of a sequential layer-by-layer deposition, additive manufacturing technologies (AM) are ideally suited to manufacture parts with complex external and internal geometries [3, 12-14]. Additionally, powder and wire feed material supplies have been known to allow for an adjustment of volume fraction of metallic components [15-17]. In particular, the directed energy deposition (DED) approach, in which powder is fed into the melt-zone and molten at every layer by a laser, can be used to fabricate components with a variable layerby-layer composition and unique microstructures [18]. Within this contribution, however, a novel laser powder bed fusion-related technology, based on liquid dispersed metal powder, is used to produce a multi-metal hybrid structure.
Carbon fibres were produced from two natural and two man-made cellulose fibres, respectively, in a high-temperature carbonisation process. The structure of the fibres was analysed by means of wide-angle X-ray scattering and Raman spectroscopy. It was found that longitudinal shrinkage of the fibres during carbonisation is correlated with the degree of orientation of cellulose crystals as determined by wide-angle X-ray scattering. Numerous micro-scale defects were found in carbonised natural cellulose fibres, particularly hemp, whereas the structural integrity of carbonised man-made cellulose was better preserved. Both Raman spectroscopy and wide-angle X-ray scattering revealed a trend of diminishing electrical resistivity with increasing structural (graphitic) order in the fibres. Overall, the electrical resistivity of cellulose-derived carbon fibres was between 40 and 70 Ω µm, which exceeds the resistivity of fossil-based carbon fibre by a factor ten.
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