3D-Printed Continuous Basalt Fiber-Reinforced Polylactic Acid Composites: Effect of Printing Parameters on Impact and Interlaminar Shear Strength

Material extrusion-based additive manufacturing has gained significant attention due to its ability to fabricate complex shapes with reduced material waste compared to conventional methods. This technology is still in its early research phase, which includes optimizing the process parameters for 3D printing composites using continuous and short fiber-reinforced thermoplastics. Basalt fiber has emerged as a promising eco-friendly material that can replace glass and Kevlar® fibers due to its lower cost and environmentally friendly properties. The mechanical properties of the composites largely depend on the process parameters involved in the material extrusion technique. This study aims to experimentally analyze the effect of print resolution, nozzle speed, and hot-end temperature on material extrusion-based 3D-printed eco-friendly continuous basalt fiber (CBF)-reinforced polylactic acid (PLA) composites and to optimize the printing parameters for achieving enhanced mechanical properties. Impact tests and short-beam shear tests were conducted on specimens printed with different printing parameters to evaluate their effect on impact energy absorption and interlaminar shear strength (ILSS). The results showed that print resolution is the most efficient factor to improve impact strength and interlaminar shear strength of the composites, followed by nozzle speed and hot-end temperature. The optimum results were obtained at a print resolution of 0.25 mm, nozzle speed of 30 mm/s, and hot-end temperature of 210 °C. The fractured surfaces of the failed specimens after testing were analyzed using scanning electron microscopy (SEM) to confirm the micro-failure modes of the specimens.