Anisotropic material behavior of 3D printed composite structures - Material extrusion additive manufacturing

Among its many benefits, additive manufacturing (AM) offers considerable freedom in the design of 3D printed parts; however, anisotropy remains a primary concern. This work investigates the final material behavior of parts fabricated with different printing strategies, and especially focused on anisotropy due to change in build orientation of the model. Further, implications in employing classical laminate mechanics for characterizing the mechanical behavior of printed parts are discussed in detail. Mechanical testing on printed test coupons revealed that build orientation significantly influenced the final properties, with properties being especially poor in parts built with upright orientation. Further, the overall performance of parts made of composite material is lower than that of polymeric parts. Finally, mechanical performance of 3D printed functional part was assessed to demonstrate the influence of printing strategy on its final material behavior under actual loading scenario. It was revealed that the mechanical performance of the printed functional part was substantially influenced by its build orientation and material composition. This investigation provides new insights of printing strategy- property relationship on mechanical performance of 3D printed parts. (c) 2020 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http:// creativecommons.org/licenses/by-nc-nd/4.0/).