Airplane Bearing Bracket Challenge

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Airplane Bearing Bracket Challenge: Optimize Airplane Bearing Bracket Design for weight, strength and additively manufacturing process via a laser/powder bed system. Introduction: Additive Manufacturing offers the opportunity to put material where it is required from a performance perspective, contrary to conventional manufacturing techniques whereby excess material is removed. A second advantage is the possibility to create double curved shapes and undercuts which are time consuming or impossible with conventional manufacturing. Analysis and Design: Within this redesign project, the current design is analyzed to identify the highest stress locations within the work envelop. These locations are critical for the AM design together with the environmental interactions; bearing interface, 4 bolt portholes, support interface and work envelop. The “Von Mises equivalent stress” is considered a good approach for calculating stresses, but it is advisable to validate the principle stresses as well. The individual principle stresses should be lower than the yield strength as well. Based on the principle “put material where it is required”, strength is created through multiple iterations and strength analysis. The submitted design has a volume and therefor a mass reduction of 69%. Further optimization is possible but not performed due to needed mesh size shrinkage and therefor increasing calculation time of the FEM analysis. Analysis and Additive Manufacturing: Besides the enormous design freedom, Additive Manufacturing has limitations. The building platform is limited in size. The distance between two layers and the grain size influence the strength and finishing roughness. Difference in strength in the layer plane and building direction is expected. Support structures are needed for protecting overhanging parts from displacing and heat dissipation towards the building platform. The costs are built up by the amount of volume printed, including the support structures, amount of building layers per part and the amount of parts per building platform. Post processing is needed; heat treatment for relieving thermal strains and stresses, EDM or milling for removing the part(s) from the building platform and removing the support structures. So, there is a tradeoff between AM costs and strength strongly influence by the part orientation. Strength is considered most important, so the building layers should be parallel to plane through all load cases. Support thickness of 0.045 in, this would add 0.16 lbs to printed material.