Title: Influence of Void Content on the Dielectric Permittivity of 3D Printed Parts

Authors: Nikolas U. Manos, Christian C. Alindayu, and Mark Peyron

DOI: 10.33599/nasampe/c.19.0817

Abstract: This study presents an investigation of the influence of testing parameters and specimen density on the dielectric properties of disc-shaped components manufactured using fused filament fabrication. The dielectric behavior of a model amorphous polymer (acrylonitrile styrene acrylate copolymer; ASA) was studied. A designed experiment was performed to investigate the impact of several factors (thickness, infill fraction, etc.) on the repeatability of the dielectric tests using a parallel plate capacitor method and performing measurements over a frequency range of 20 Hz to 1 MHz. The testing guidelines in the ASTM D150 standard for molded parts were investigated and were found to produce consistent results when applied to 3D-printed parts, and specific experimental conditions were identified to achieve reproducible results. A strong dependence on specimen void content was observed for both the relative permittivity and dielectric loss tangent. Results were analyzed as a composite system with a continuous polymer phase and dispersed air-void phase. It was shown that most heterogeneous models do not account for the orientation and shape of dispersed voids and do not accurately represent the observed dielectric behavior. A power law model that includes a shape factor related to the axis of the voids closely matched the empirical relative permittivity data. The dielectric loss tangent data were also used was to develop a linear empirical model.

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Conference: CAMX 2019

Publication Date: 2019/09/23

SKU: TP19-0817

Pages: 12

Price: $24.00