Effect of infill and density pattern on the mechanical behaviour of ABS parts manufactured by FDM using Taguchi and ANOVA approach

Purpose: The present work aims to investigate the effect of many infill patterns (rectilinear, line, grid, triangles, cubic, concentric, honeycomb, 3D honeycomb) and the infill density on the mechanical tensile strength of an Acrylonitrile Butadiene Styrene (ABS) test specimen manufactured numerically by FDM. Design/methodology/approach: Computer-Aided Design (CAD) software has been used to model the geometry and the mesostructure of the test specimens in a fully automatic manner from a G-code file by using a script. Then, a Numerical Design of Experiments (NDoE) has been carried out by using Taguchi method and the Analysis of Variance (ANOVA). The tensile behaviour of these numerical test specimens has been studied by the Finite Element Analysis (FEA). Findings: The FEA results showed that a maximal Ultimate Tensile Strength (UTS) was reached by using the ‘concentric’ infill pattern combined with an infill density of 30%. The results also show that the infill pattern and the infill density are significant factors. Research limitations/implications: The low infill densities of 20% and 30% that have already been used in many previous studies, we have also applied it in order to reduce the time of the simulations. Indeed, with high infill density, the simulations take a very excessive time. In an ongoing study, we predicted higher percentages. Practical implications: This study provided an important modelling tool for the design and manufacture of functional parts and helps the FDM practitioners and engineers to manufacture strong and lightweight FDM parts by choosing the optimal process parameters. Originality/value: This study elucidated the effect of various infill patterns on the tensile properties of the test specimens and applied for the first time a NDoE using numerical test specimens created by the mesostructured approach, which considerably minimized the cost of the experiments while obtaining an error of 6.8% between the numerical and the experimental values of the UTS

Topology optimization of a 3D part virtually printed by FDM

Purpose This research work aims to exhibit the possibility to topologically optimize a mesostructured part printed virtually by FDM taking into account the manufacturing parameters. Design/methodology/approach The topology optimization of a 3D part printed by FDM was carried out using the software ABAQUS. On the other hand, a numerical approach using a script based on G-code file has been achieved to create a virtual model. Then, it was optimized according to the Solid Isotropic Material with Penalization (SIMP) method, which minimizing the strain energy was the objective function and the volume fraction of 30% was the constraint. Findings The final topological optimization design of the virtual model is approximately similar to the homogeneous part. Furthermore, the strain energy of the virtual model is less than the homogeneous part. However, the virtually 3D optimized part volume is higher than the homogeneous one. Research limitations/implications In this study, we have limited our study on one layer owing to reduce the simulation time. Moreover, the time required to optimize the virtual model is inordinate. The ensuing study, we will optimize a multiple layer of the mesostructure. Practical implications Our study provides a powerful method to optimize with accurately a mesostructure taken into consideration the manufacturing setting. Originality/value In this paper, we have studied through an original approach the potential of topology optimization of a 3D part virtually printed by FDM. By means of our approach, we were able to optimize topologically the 3D parts printed by FDM taking into account the manufacturing parameters