Experimental Modal Analysis and Characterization of Additively Manufactured Polymers

Abstract

Modern 3D printed components are finding applications in dynamic structures. These structures are often subject to dynamic loadings. To date, research has mostly focused on investigating the mechanical properties of these 3D printed structures with minimum attention paid to their modal analysis. This work is focused on performing experimental modal analysis of 3D printed structures. The results show that the adhesion type has the most significant impact on the vibration response and parameters obtained from the modal analysis. The average dynamic modulus, natural frequency, and damping coefficient increased by approximately 12.5%, 5.5%, and 36%, respectively, for the specimens printed using skirt adhesion compared to those printed using raft adhesion. SEM analysis suggests that the 3D printed specimens with skirt adhesion yielded flattened layers, while raft adhesion resulted in rounded layers. The flattened layers of the specimens with skirt adhesion are likely an indication of an enhanced heat transfer between the 3D printer bed and the specimen. The printed specimens with skirt adhesion are in direct contact with the printer bed during the printing process. This enhances the heat transfer between the specimen and the printer bed, causing the layers to flatten out. The enhanced heat transfer yields a better inter-layer diffusion, resulting in improved physical bonding at the layers’ interface. The improved bonding yields higher stiffnesses and natural frequencies. For the specimens with skirt adhesion, the improved heat transfer process is also likely responsible for the enhanced damping properties. The strengthened inter-layer bonding at the layer–layer interface provides better energy dissipation along the contact lines between the layers.

Failures and Flaws in Fused Deposition Modeling (FDM) Additively Manufactured Polymers and Composites

“…This would, of course, depend on the adhesion between the layers. A way to alleviate the inconsistent heating between the thermocouples and the print bed is to use the skirt adhesion type build plate [40]. It was found in a study conducted by Nguyen et al that the adhesion type was the most significant parameter tested that affected the vibrational response of the print.…”

Experimental Investigation and Prediction of Mechanical Properties in a Fused Deposition Modeling Process

“…ABS plastic gets its stiffness and processability from styrene, which is made by dehydrogenating ethyl benzene. Acrylonitrile butadiene styrene has the chemical formula C 8 H 8 •C 4 H 6 •C 3 H 3 N [23][24][25][26]. ABS has a low melting point, which enables it to be easily used in 3D printing.…”

In-situ measurement of anisotropic Young’s modulus in fused deposition modeling printed cantilevers

“…Hence, we potentially simplify any future theoretical and simulation analyses by the utilization of simplified shape outline and effective Young's modulus for the corresponding printing direction. While the printing orientation based mechanical property differences were reported in literature based on conventional elasticity (also referred to as tensile or tension) tests [23,[27][28][29][30][31][32][33], in this study we deduce the Young's modulus in-situ, based on observing the mechanical resonance of the device under test. On top its contribution to the 3D printed microsystems, the presented study also sets a basis for the millimeter scale models for molecular scale anisotropy of crystalline (i.e.…”