Numerical analysis and multi-objective optimization of FDM process parameters.

Material extrusion based fused deposition modeling (FDM) is important type of additive manufacturing (AM) technologies. This study focuses on numerical analysis and multi-objective optimization of FDM process parameters for the manufacturing of micro-turbo machinery impellers. A three dimensional model of impeller is converted into Standard Tessellation Language (STL) format and separate G-code file is generated for each specimen with consideration of two important process parameters, layer thickness and infill density. FDM process is simulated with numerical simulation tool Digimat-AM software to predict the responses residual stress, deflection, material consumption and printing time. Results of the simulation is analysed with response surface methodology (RSM) to predict the relationship between process parameters and responses. Analysis of variance (ANOVA) is utilised to validate the significance of developed model and identify significant process parameters and its interactions. Further, optimal setting of process parameters is identified with response optimizer tool as 0.321798 mm layer thickness and 20% infill density. The corresponding optimum response values indicated residual stress 36.8074 Mpa, deflection 0.518879 mm, material consumption 13.3117 g, and printing time 60 min. Significant impact of layer thickness and infill density is observed on residual stress, deflection, material consumption and printing time. These findings can be used to optimize the FDM process for manufacturing of high precision parts. [ABSTRACT FROM AUTHOR]