Session: 01-03-01: Advanced Manufacturing for Aerospace Structures

Paper Number: 106951

106951 - Mechanical and Material Characterization of 3d Printed Continuous Fiber Reinforced Photopolymer Matrix Composites 

Modern manufacturing methods for long fiber reinforced polymer matrix composites require significant overhead in the form of molds, vacuum packing, man hours, curing chambers, and more. Additive manufacturing offers an attractive method for rapid prototyping and low overhead manufacturing of such composites. No tool up would be required, as the same printing platform can be used for nearly any manufacturing task. Photopolymers cured during printing offer a way to eliminate the need for thermal cure chambers. And the fully computer-controlled printing process will eliminate a significant amount of labor. Yet relevant 3D printing processes are only in early stages of testing and adoption, with wide variations in their properties and capabilities.

This paper will outline a novel additive manufacturing method for long fiber reinforced photopolymer matrix composites and recount mechanical and material data from printed samples. The 3D printer that will be used is based on direct ink write 3D printing modified to extrude a continuous fiber impregnated with a UV-curable resin. This is a forced extrusion method meant to push resin and fiber out of the machine’s nozzle at a constant rate. The resin/fiber mixture is cured upon extrusion by a set of UV lights focused on the point of deposition, providing a means of in-situ cure that eliminates the need for an explicit curing stage later in the manufacturing process. The efficacy of the method and the produced composite material will be examined. Printed specimens will be analyzed to determine the printable fiber volume fraction using burn off tests. They will be characterized with tensile testing and compared to molded samples of the same composition. The void content, layer interface quality, and surface finish produced by the novel manufacturing method will also be discussed using evidence from microscopic photography.

Presenting Author: Yingtao Liu University of Oklahoma

Presenting Author Biography: Dr. Yingtao Liu is an Associate Professor in the School of Aerospace and Mechanical Engineering at the University of Oklahoma.

Authors:

Peter Sandell University of Oklahoma
Christopher Billings University of Oklahoma
Yingtao Liu University of Oklahoma