Investigation and Optimization of Processing Parameters Affecting the Mechanical Properties of Carbon Particle-Reinforced Thermoplastic Polyurethane Samples Fabricated via Fused Filament Fabrication

This study investigates the optimization of 3D printing parameters for enhancing the mechanical properties of conductive thermoplastic polyurethane (TPU) composites using a filament containing Lampblack particles for improved electrical conductivity. A systematic approach, including response surface methodology and design of experiments, was employed to optimize process parameters such as cooling speed/fan speed (CS), nozzle temperature (NT), and bed temperature (BT). The objective was to improve mechanical properties such as tensile strength (UTS), yield strength (YS), elongation at break (F-Strain), modulus of toughness (MoT), flexural strength at 5% strain (FS5), and flexural modulus (FM). The study utilized ASTM standards for mechanical testing. Results revealed significant effects of CS, NT, and BT on mechanical properties, with optimal combinations of parameters identified for improved performance. A desirability optimization approach led to the selection of process parameters (CS = 60%, NT = 250 degrees C, and BT = 60 degrees C), resulting in improved tensile and flexural properties, i.e., UTS = 4.71 MPa, YS = 2.239 MPa, E = 12.1 MPa, F-Strain = 172.95%, MoT = 481.1 MPa, FM = 20.8 MPa, and FS5 = 1.129 MPa. This study provides an understanding of the influence of 3D printing parameters on conductive TPU composites with potential applications in flexible electronics and wearable devices.