Integrating experimental characterization and machine learning for predicting the tensile behaviour of PLA–MWCNTs FFF composites
摘要
This study aims to develop an integrated experimental and machine learning framework for accurately predicting the tensile behaviour of high-content multi-walled carbon nanotubes (MWCNTs)-reinforced polylactic acid (PLA) composites fabricated using fused filament fabrication (FFF). The composite filaments were extruded using a single-screw process and 3D-printed under varied raster orientation, infill density, and layer height. Mechanical characterization through ASTM-standard tensile testing revealed a maximum tensile strength of 54.269 MPa, highlighting the critical influence of process parameters on interlayer bonding. X-ray diffraction analysis confirmed a crystallinity index increase from 36% (neat PLA) to 47.41% for PLA–MWCNTs composites, while SEM imaging demonstrated uniform MWCNTs dispersion without agglomeration. To predict tensile strength and reduce experimental iteration, five machine learning models—Linear Regression, Random Forest, AdaBoost, Ridge Regression, and K-Nearest Neighbors—were trained and evaluated. Among them, LR and RR achieved the highest accuracy with R2 = 0.99, outperforming ensemble and instance-based models. The proposed framework can be applied to optimize process parameters, reduce experimental effort, and support the design of high-performance polymer nanocomposites for applications in aerospace, automotive, and biomedical engineering.