Analysis of Electrical Conductivity in Chopped Carbon Fiber/High‐Density Polyethylene Composites Under Tensile Alignment: Experimental and Simulation Approaches

ABSTRACT The low electrical conductivity of polymer‐based composites limits their applicability to electromagnetic interference shielding in the automotive industry. This study aimed to enhance the electrical conductivity of composites composed of chopped carbon fiber (CCF) and high‐density polyethylene (HDPE). Composite samples of CCF/HDPE were fabricated using a take‐up machine, which used a unique tension alignment method following extrusion. The impact of various manufacturing variables, such as fiber content, length, and draw ratio (DR), on electrical conductivity was examined. The highest conductivity measured was 2.808 S/cm for CCF with a length of 1 mm, 10 wt%, and a DR of 2. In addition, percolation theory was utilized to compare and predict the effects of these manufacturing variables. Electrical conductivity improved as the length, content, and DR of the CCF increased. The experiments were simulated considering both CCF entanglement and alignment. The findings revealed a significant increase in electrical conductivity with a higher CCF weight percentage and DR surpassing the percolation threshold. The higher DR aided in aligning the fibers, resulting in enhanced electrical conductivity in the aligned direction. Furthermore, electrical conductivity was enhanced as the length of the CCF decreased.