Design optimization and validation for additive manufacturing: a satellite bracket application

Abstract

In the aerospace industry, structures are designed (or aimed) to be as light as possible to reduce emissions and carbon footprint; additionally, they are designed to improve fuel efficiency and service life while satisfying the mechanical requirements. Due to the development of additive manufacturing technology, complex structures with higher mechanical performance obtained through topology optimization (TO) can be manufactured. In this study, the overall process from part selection to qualification for a space industry-engineering application is described. First, the design space of the selected aluminum bracket is generated, and TO is performed by using stress and minimum member size constraints. The bracket is re-designed with respect to the TO output data as a reference and then the new design is validated numerically by structural analyses. The validated design is manufactured using the selective laser melting method, and heat treatment is applied to obtain more homogenized microstructure. Mechanical tests are performed on the manufactured brackets under the qualification loading conditions and post-testing examination processes are applied with metallurgical and metrological tests. According to the test results, the qualification process of the bracket is successfully completed. Consequently, the new bracket designed with TO was found to be 25% lighter than the existing design; thus, it has a huge improvement in fuel efficiency and environmental impact during the launching phase.