Materials selection of 3D-printed continuous carbon fiber reinforced composites considering multiple criteria

3D-printed composites reinforced with continuous carbon fibers have great potential to be adopted in various engineering fields, e.g., urban rail transit and aerospace. However, different manufacturing processes of 3D printing have great impacts on the properties of composites. The optimal material selection to meet given practical engineering demands usually requires that a compromise is struck between conflicting criteria. This paper studies the mechanical properties of a polyamide-based composite combined with short and continuous carbon fibers and establishes a systematic hierarchical structure of multiple criteria for materials selection with the consideration of environmental, economic, social and physical impacts. An integrated multi-criteria decision-making approach that contained the fuzzy best-worst method and fuzzy G-VIKOR method is presented to solve the composite materials selection problem. A front-end thin-walled underframe structure of high-speed train, as an empirical application, is adopted to verify the application of this solution methodology and 6 L-2 is selected as the optimal alternative under this engineering background. Sensitivity analysis, validation and practical implications are conducted in this research. The results confirm that this research provides an effective tool to solve the composite materials selection problem and some reference gist for designers.