Tensile Properties of 3D-printed Continuous-Fiber-Reinforced Plastics

Abstract

Obtaining parts made of composite materials through 3D Printing Additive manufacturing have fully proved their usefulness due to several advantages such as: the possibility to directly create complex shapes without going through the classic process of transforming the semi-finished products into finished parts through technologies that consume resources and energy and are unfriendly to the environment. The main disadvantage of the parts made by 3D Printing technologies is that they are less resistant from a mechanical point of view. This can be solved by the development of 3D printers capable of printing composite parts consisting of a plastic matrix reinforced with continuous fibers. This research focuses on studying 4 types of 3D-printed Continuous-Fiber-Reinforced Plastics (CFRP) from the point of view of their mechanical properties: Onyx - rigid nylon in which micro carbon fibers are inserted and Onyx reinforced with carbon, glass or Kevlar fiber. Standardized specimens were made for the uniaxial tensile test and the experimental program was designed evaluating: the Elastic modulus [GPa], the Maximum Tensile stress [MPa], the Tensile strain at maximum Tensile stress [mm/mm]. The principal strains were also determined, using the digital image technique made using the Aramis system from GOM. The experimental tests confirm that these new materials will be serious candidates to be used in engineering applications in various fields.