Low-Velocity Impact Characteristics of 3D-Printed Poly-Lactic Acid Thermoplastic Processed by Fused Deposition Modeling

The present research has focused on investigation into the low-velocity impact (LVI) behavior of 3D-printed poly-lactic acid thermoplastic material processed by fused deposition modeling. Four different infill density (ID) percentages, namely 40%, 60%, 80%, and 100%, were manufactured and subjected to the LVI test with 50 J energy input. The specimens were impacted using 12.7-mm hemispherical portion with conical head (ϕ 20 mm) striker which introduced two penetration stages. The impact characteristics in terms of velocity–time, force–time, and energy–time curves were investigated and reported. The penetration velocity limit, penetration energy, peak energy, and peak force were measured and discussed. The results revealed that the impact characteristics started to increase as the function of ID. The surface topography and fractured surfaces were examined using SEM. The fracture surfaces of 80% and 100% ID samples exhibited more viscous plastic deformation, indicating more energy absorption and load-carrying capacity.