Bio-inspired additive manufacturing of PLA composites reinforced with Alangium salviifolium bark fibers for 3D printing applications

The increasing demand for sustainable materials in additive manufacturing (AM) has driven significant interest in natural fiber–reinforced biodegradable composites. This study investigates the feasibility of using Alangium salviifolium bark (ASB) fibers as a novel bio-based reinforcement for polylactic acid (PLA) in fused deposition modeling (FDM) 3D printing. Composite filaments were fabricated by incorporating ASB fibers at different loadings (1–4 wt.%) into PLA using a single-screw extrusion process, followed by the fabrication of test specimens in accordance with ASTM standards. Mechanical characterization was carried out through tensile, flexural, compression, hardness, impact, and wear tests, while morphological and structural analyses were performed using scanning electron microscopy (SEM) and X-ray diffraction (XRD). The results demonstrated a significant enhancement in the mechanical performance of PLA with ASB fiber incorporation, with optimum properties achieved at 2 wt.% fiber loading. At this concentration, tensile strength (50.44 MPa), flexural strength (61.03 MPa), compression strength (55.67 MPa), and Young’s modulus reached maximum values compared to neat PLA. Impact strength improved by approximately 29%, and hardness showed a consistent increase with increasing fiber content. Improved wear resistance was observed at 1–2 wt.% fiber loadings, while higher concentrations led to performance deterioration due to fiber agglomeration. SEM analysis confirmed uniform fiber dispersion and strong interfacial bonding at lower loadings, whereas XRD results indicated enhanced crystallinity up to 2 wt.% reinforcement. Overall, the study establishes ASB fibers as an effective and sustainable reinforcement for PLA, highlighting their potential for eco-friendly structural and functional applications in additive manufacturing.