Title: Part 2: The Efect of Defects on Traditional and 3D Printed Composite Performance – Test Results

Authors: Aaron M. Balles

DOI: 10.33599/nasampe/s.22.0813

Abstract: Traditional Polymer Matrix Composites (PMC) and Additive Manufacturing (AM) (3D printing) of composites have flourished in recent years. All contain defects. It is unknown if common defects (air voids, resin rich areas, delaminations) affect AM PMCs the same as traditional PMCs. This work compares the flexural/tensile response of pre-preg laminates with FDM-type AM PMC specimens with one of three defects. Two of the strongest chopped fiber-reinforced nylon filaments, and a graphite/epoxy unidirectional pre-preg were used to fabricate “Control” and “Defective” tensile and flexural specimens. Although the absolute strengths and stiffness’ of the two types of composites were different, some failure trends were similar. Results show common fracture locations for all tensile/flexural specimens containing air or resin rich areas. Defects decreased Toughness (strain-to-failure) in all tensile and flexural tests except one AM material’s air voids. Strangely, the flexural stiffness of specimens with defects increased for AM specimens, but decreased for pre-preg specimens. Ultimate strength decreased the most in the resin rich areas for both types of specimens for all materials. Pre-preg tensile tests were not yet completed due to tab failures. All defects caused significantly reduced tensile properties for AM specimens. Type of loading, defect location, and FDM fabrication techniques can significantly affect mechanical properties. This paper is a continuation of “PART 1: THE EFECT OF DEFECTS ON TRADITIONAL AND 3D PRINTED COMPOSITE PERFORMANCE – SPECIMEN DEVELOPMENT.”

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Conference: SAMPE 2022

Publication Date: 2022/05/23

SKU: TP22-0000000813

Pages: 15

Price: $30.00