Abstract

The utilisation of three-dimensional (3D) printing has become a well-established method for fabricating structural components across various materials such as polymers, metals and ceramics. Within this domain, multi-material 3D printing emerges as a pivotal advancement, offering prospects for rapid manufacturing, customised design, and structural innovation. Particularly, the incorporation of recycled materials into multi-material printing holds promise for promoting sustainability and recyclability in manufacturing processes. By leveraging multi-material printing techniques and incorporating recycled materials, this study aims to advance the sustainability agenda within manufacturing practices while concurrently exploring avenues to enhance material performance for practical engineering applications. This study focuses on the multi-material printing of pure polylactic acid (PLA) alongside recycled polylactic acid (rPLA), employing fused deposition modelling (FDM) as a cost-effective 3D printing technique. The research aims to identify the optimal composition for achieving desired material properties by exploring different percentages and layer placements of recycled material in combination with pure PLA. Detailed analysis of the mechanical properties of these 3D printed components was conducted, with the experimental results further validated through analysis of variance. The results of this study emphasis the mechanical advantages associated with the utilisation of multi-material 3D printing techniques. Moreover, the incorporation of both PLA and rPLA materials highlights the potential sustainability benefits inherent in these approaches.