Influence of
3D
Printing Parameters on the Electromagnetic Shielding Performance of Multi‐ Walled Carbon Nanotubes/Rice Husk Charcoal/Polylactic Acid Composites
Yufeng Sun, Jingzu Li, Hengyu Liu, Mingyang Liu, Qinglei Liu, Zhibo Zhang, Jilai Ying, Ing Kong ABSTRACT
The continuity and orientation of carbon nanomaterials in the polylactic acid (PLA) matrix directly determine the efficiency of the conductive network and the composite's capability to shield against electromagnetic interference (EMI). The accumulation of fillers or local voids often leads to the discontinuity of the network, increasing the interface resistance and weakening the overall conductivity. To address this issue, this study focused on the multi‐walled carbon nanotube/PLA (MWCNT/PLA) composite material (with an MWCNTs mass fraction of 9%) using silane‐coupling‐treated rice husk carbon (RHC) as the dispersant as the research object, and systematically explored the influence of various 3D printing parameters on its electromagnetic shielding effectiveness. By adjusting the thicknesses to 0.1 and 0.2 mm, respectively and using three filling patterns (zigzag, grid, and triangular), a series of MWCNT/RHC/PLA composites were produced, and their microscopic morphology (SEM), crystallization properties (XRD), tensile properties, electrical conductivity and EMI shielding effectiveness (SE) were characterized and analyzed. It was found that optimizing the 3D printing parameters can significantly enhance the EMI shielding effectiveness of the PLA‐based composites. The optimal combination was determined to be the zigzag pattern with a 0.1 mm layer thickness, yielding a tensile strength of 69.23 MPa, an electrical conductivity of 5.14 S/m, an EMI SE of 36.91 dB. The dominant shielding mechanism was reflection. This research provides a theoretical basis and process reference for the preparation of high‐performance, environmentally friendly, PLA‐based 3D‐printed electromagnetic shielding materials and their applications in automotive electronics.