Modelling of tensile strength of 3D printed PETg, ABS and ASA based novel filament

This assessment is performed to model the tensile properties of novel filament comprising PETg, ABS, and ASA. Earlier researches focused on evaluation of mechanical properties of a single material. The composite filament was prepared by mixing the raw granules of all three selected materials, followed by de-moisturizing, melting and injection moulding to form a filament of 1.75 mm diameter. Response Surface Methodology (RSM) was employed for planning the trials using layer thickness (016 to 0.24 mm), speed of print (30 to 50 mm/sec) and density of infill (30 to 90%) as the machine variables. The result of tensile strength revealed that it is governed not only by the thickness of the layer (probability value < 0.0001) and density of infill (probability value < 0.0001) but also by their quadratic and interaction terms. Tensile strength in the range of 30.1–45.3 MPa was achieved which is better than the previously studied composites. This depicts the non-linear nature of the process. Furthermore, the variance analysis confirms the significance of the quadratic model with minimum residual error and strong agreement between the predicted and experimental values. Better tensile properties are achieved with thin layers and high infill density. Print speed showcases a negligible influence but contributes inversely when combined with other variables. The R2 value of 0.9931 indicates 99.31% variability in tensile strength is explained by the model and represents that the present model is reliable and predictive. The residual error of 0.27% during the model validation exhibits the validity and precision of the model.