Evaluation of Technologies for the Fabrication of Continuous Fiber Reinforced Thermoplastic Parts by Fused Layer Modeling

In this research technologies for the production of continuous fiber-reinforced thermoplastics using additive manufacturing are investigated and evaluated. The focus is on the “Fused Layer Modeling” (FLM) process, which is based on an additive, thermoplastic extrusion process. The possibility of combining the plastic filament with continuous fibers allows a specific fiber reinforcement to be introduced into the part to increase the mechanical properties. First, an overview of the technologies for processing continuous fibers is presented. These strategies differ in the design of the machine (hardware) and the possibilities for the constructive insertion of the continuous fibers in slicing (software). The differences of the technologies are the processing method of the fiber as well as the fiber roving used in the extrusion process. The maximal fiber volume content and the interlaminar fiber-matrix adhesion are investigated in various commercial technologies by means of tensile and bending tests. In conclusion, the different technologies are evaluated with regarding the maximal fiber volume content and quality of interlaminar fiber-matrix adhesion.