REPEATABILITY OF A TOPOLOGY OPTIMIZED TAPERED BOX BEAM ADDITIVELY MANUFACTURED WITH ELECTRON BEAM MELTED TI-6AL-4V

摘要

In order far metal additive manufacturing to fully break into the commercial aircraft industry the process has to be stable and repeatable. The product safety of high-quality serial production components is directly related to manufacturing repeatability. In this study a tapered box beam resembling a scaled down commercial aircraft engine pylon forward strut box is designed for additive manufacturing using 3D topology optimization as a guide. The topology optimization algorithm initially sized the structure for maximum stiffness, then the resulting CAD model was redesigned and analyzed for maximum principal stress to reduce the weight. The final design had an asymmetric organic-like truss structure that was manufactured in two halves out of titanium using an Arcam A2X electron beam powder bed fusion machine. A trial build helped to determine the proper support strategy to achieve quality specimens with tight tolerances that would facilitate assembly. To test the manufacturing repeatability a series of three builds was executed to produce six beam specimens for follow-on analysis and strength testing. This paper describes the design, analysis, and manufacturing process for a topology optimized taped box beam that is intended for future ultimate strength testing and analysis.