Utilization of waste slate powder in poly(lactic acid) based composite for 3D printer filament

Abstract

This work aims to develop and validate a novel composite material for fused deposition additive manufacturing utilizing poly (lactic acid) (PLA) and discarded slate powder. The slate powder is mixed into PLA filaments at varying percentages (0%, 5%, 10%, and 15%) using a twin screw extruder. The resulting filaments are used in a 3D printer to print the test specimens. The tensile strength of the testing specimens is improved up to 5 wt% by incorporating slate powder. In contrast, the tensile modulus, hardness, and impact strength are raised with slate powder up to 15 wt% in PLA-based filament by 19.03%, 10.67%, and 31.63%, respectively. The maximum flexural strength and modulus values are 93.25 MPa and 4.15 GPa, respectively, achieved at 10 wt% slate powder content PLA matrix. Moreover, slate powder's presence significantly affects the composites' dynamic mechanical properties, such as storage, loss modulus, and damping factor. The composite's entanglement density, C-factor, adhesion efficiency, and reinforcing efficiency factor are investigated using dynamic mechanical properties and correlated with their structural integrity. Results show that 10 wt% slate powder in the PLA matrix is sufficient for their successful application.