Topological optimization and lattice structures for aerospace components

Low product weight in combination with high mechanical properties play a crucial role in reducing operating costs in the aerospace industry. For this purpose, topology optimization and lattice structures are used. Additive manufacturing processes enable the production of optimized parts with geometric complexity. So far, no clear and comprehensive approach for designing a machine part with reduced weight in this way has been presented. The aim of this work was to map the topology optimization process with the use of lattice structures, corrected by experimentally determined production limits. Furthermore, the work deals with the implementation of the proposed methodology in optimization of a real machine part, its production from AlSi10Mg metal powder using selective laser melting technology, and verification of its manufacturing accuracy and vibration response. To determine the production limits, a series of lattice strut tests were performed. According to dimensional, weight and porosity analysis of lattice struts, a minimum applicable cross-section of the strut was chosen. Struts with this cross-section were subsequently applied into the beam samples with the BCC and BCCz lattice structure. Based on the mechanical response, the BCCz lattice structure was selected for application in the optimized part. For a more accurate mechanical behaviour prediction, based on actual lattice structure response, corrected elasticity modulus and yield strength value for BCCz lattice type were determined. These parameters were applied into FEM simulation in the lattice optimization phase. After solving the problem of lattice structure geometry export from FEM software, the optimization methodology could be completely defined, the part was manufactured, and the design potential was verified