TY - JOUR U1 - Zeitschriftenartikel, wissenschaftlich - begutachtet (reviewed) A1 - Heitkamp, Tim A1 - Kuschmitz, Sebastian A1 - Girnth, Simon A1 - Marx, Justin-Dean A1 - Klawitter, Günter A1 - Waldt, Nils A1 - Vietor, Thomas T1 - Stress-adapted fiber orientation along the principal stress directions for continuous fiber-reinforced material extrusion JF - Progress in Additive Manufacturing N2 - A proven method to enhance the mechanical properties of additively manufactured plastic parts is the embedding of continuous fibers. Due to its great flexibility, continuous fiber-reinforced material extrusion allows fiber strands to be deposited along optimized paths. Nevertheless, the fibers have so far been embedded in the parts contour-based or on the basis of regular patterns. The outstanding strength and stiffness properties of the fibers in the longitudinal direction cannot be optimally utilized. Therefore, a method is proposed which allows to embed fibers along the principal stresses into the parts in a load-oriented manner. A G-code is generated from the calculated principal stress trajectories and the part geometry, which also takes into account the specific restrictions of the manufacturing technology used. A distinction is made between fiber paths and the matrix so that the average fiber volume content can be set in a defined way. To determine the mechanical properties, tensile and flexural tests are carried out on specimens consisting of carbon fiber-reinforced polyamide. In order to increase the influence of the principal stress-based fiber orientation, open-hole plates are used for the tensile tests, as this leads to variable stresses across the cross section. In addition, a digital image correlation system is used to determine the deformations during the mechanical tests. It was found that the peak load of the optimized open-hole plates was greater by a factor of 3 and the optimized flexural specimens by a factor of 1.9 than the comparison specimens with unidirectional fiber alignment. KW - Continuous fiber KW - Curvilinear fiber KW - Design for additive manufacturing KW - Fiber reinforced additive manufacturing KW - Material extrusion KW - Principal stress KW - Extrudieren Y1 - 2022 UN - https://nbn-resolving.org/urn:nbn:de:bsz:960-opus4-24064 SN - 2363-9512 SS - 2363-9512 U6 - https://doi.org/10.25968/opus-2406 DO - https://doi.org/10.25968/opus-2406 SP - 19 S1 - 19 ER -