Topology optimization and manufacturing of engine bracket using electron beam melting

Abstract

Nickel-based alloys are widely used for aerospace applications since they exhibit tremendous mechanical strength under extreme conditions. Additive manufacturing (AM), especially electron beam melting (EBM), technology is of interest due to its potential of direct digital manufacturing of highly complex fully functional light-weight critical components such as engine brackets. Most critical tasks of the brackets in their use, are to damper the vibration and support the engine weight. Consequently, it is desired simultaneously to reduce weight and maintaining good mechanical properties where the topology optimization is the right tool.  In this study, the reference and weight-reduced brackets are fabricated via EBM method, and then followed by subjecting to the hot isostatic pressing (HIP) procedure. The engine bracket is weight reduced with a value of 32.08% utilizing a developed finite element analyses (FEA) based topology optimization. Furthermore, the effect of different loading conditions on the topology optimization of the EBM-built Inconel 718 bracket is studied. The mechanical property values for the FEA are obtained based on experimental data. The reference and topologically optimized brackets are subjected to the tensile tests using a tailor-made fixture and the area under the ‘Load vs. Tensile Extension’ curves are estimated to obtain average energy values using software where a 16.3% energy increase is witnessed.