Mechanical Properties and Abrasion Resistance of 3D Printed Lightweight CF-Reinforced PLA/ABS Composites Using Design of Experiments

The present research work is to evaluate the three-body abrasive wear behaviour of composites of Polylactic Acid (PLA) and Acrylonitrile Butadiene Styrene (ABS) reinforced with Short Carbon Fibres (SCFs), fabricated by fused deposition modelling (FDM). Commercially available polymers for applications in 3D printing, PLA, PLA/SCFs and ABS/SCFs composites made by FDM were investigated. Dry sand abrasion tester having rubber wheel is used for implementing three-body abrasive wear experiments. Taguchi design of experiments is adopted for developing the experimental design and optimisation of parameters. Hardness, impact strength, specific wear rate (Ks) and worn surface morphologies of these samples were compared. The incorporation of SCFs raised the Ks of thermoplastic composites. These outcomes could be explained by the SCFs significantly reducing final elongation at break, which is a crucial aspect of abrasive wear performance. Micro-cutting, plastic deformation and matrix pitting are the main wear processes in neat PLA/ABS. The wear mechanisms in case of SCFs reinforced composites are ploughing, micro-cutting, fragmentation of wear debris, and severe weakening of the fibre surface and delamination. When fiber reinforcement is added to any matrix, the wear behaviour of polymer-based composites will alter. In this study, SCFs reinforcement was used to improve the mechanical characteristics of PLA/ABS polymers. However, effects of SCFs on specific wear rate of PLA/ABS composites are not always positive.