New lightweight optimization method applied in parts made by selective laser sintering and polyjet technologies

Abstract

The continuous evolution of materials and technologies of additive manufacturing has led to a competitive production process even for functional parts. The capabilities of these technologies for manufacturing complex geometries allow the definition of new designs that cannot be obtained with any other manufacturing processes. An application where this capability can be exploited is the lightening of parts using internal structures. This allows to obtain more efficient parts and, at the same time, reduce the costs of material and manufacturing time. A new lightweight optimisation method to optimise the design of these structures and minimise weight while keeping the minimal mechanical properties is presented in this paper. This method is based on genetic algorithms, metamodels and finite element analysis (FEA). This combination reduces the number of FEA simulations required during the optimisation process, thereby reducing the design time. This methodology is experimentally applied to a reference geometry oriented both for selective laser sintering (SLS) and Polyjet technologies. In both cases, an optimised and a non-optimised design are manufactured and tested in order to experimentally compare the stiffness results between them. The optimum design achieved a specific stiffness 72.82% higher than the non-optimised design in the SLS case study, and 3.14 times higher in the Polyjet case study.