Title: Microstructures Effect on Anisotropic Thermal Conduction in Additive Manufactured Composites

Authors: Harry Zhou, Tiantian Ke, Soroush Azhdari, Sergii Kravchenko

DOI:

Abstract: This study investigates the impact of microstructure on the anisotropic effective thermal conduction (ETC) of short carbon fiber-reinforced polyetherimide (SCF/PEI) composites produced via extrusion-based additive manufacturing. While microstructural variations have been shown to influence the ETC of SCF/PEI, the effect of void morphology and orientation on experimentally measured ETC remains poorly understood. This work characterizes fibers and voids, and uses sphericity, compactness, elongation, and orientation as descriptors to examine the effect of void morphology on the ETC. Three specimens were produced using Fused Filament Fabrication and Fused Pellet Manufacturing. Nozzle diameter, layer height, and bead width were varied to create microstructures with distinct fiber and void characteristics. Micro-computed tomography was used to extract fiber and void orientations, volume fractions, and morphologies. Directional ETC was measured along printing and transverse build axes using the Transient Plane Source method. Results show that void morphology influenced ETC, voids elongated along the testing direction were found to lower ETC, compared to spherical or randomly shaped voids. These findings highlight the effect of void characteristics on the thermal pathways in SCF/PEI parts.

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Conference: SAMPE 2026

Publication Date: 2026/04/27

SKU: 71

Pages: 12

Price: $24.00