Investigation of Delamination in the Drilling of PLA Specimens with Different Lattice Structures

Abstract

Aim of this study examines the impact of processing parameters and lattice structures on delamination during the drilling of cylinder PLA (Polylactic acid) parts. The parts were designed with four different lattice structures (gyroid, I-WP, nevoius, and diamond) and produced using a 3D printer. A 5 mm HSS drill was used to drill from the center point. After drilling, images of the entrance and exit holes were captured using a digital microscope. The delamination, burr, and circularity around the hole were analyzed. The results showed that the Gyroid and I-WP lattice structures had the lowest delamination at the entrance and exit holes. No burr was observed at the entrance of the specimens. The Nevoius lattice structure exhibited the lowest burr value at the hole exit and entrance, as well as the lowest exit circularity deviation. Among the samples, the highest delamination was observed at the hole entrance in I-WP (0.5601), while the lowest delamination was observed in Gyroid (0.5423). At the hole exit, the highest delamination was observed in Gyroid (0.6229), and the lowest delamination was observed in I-WP (0.5426).