Electron beam melting technology offers various benefits like the reduced product cycle time, customization, flexibility, high energy density and less material wastage. However, electron beam melting still suffers from redundant usage of support structure material while fabricating overhang structures. The support structures not only consume additional material, but also require additional time for their design and removal. The optimized support structures have to be designed in such a way that they consume minimum material, are easy to remove and are free from defects. The aim of the current study is to study the effect of support design and process parameters on the performance of the support structures (cost and quality) during additive manufacturing of Ti6Al4V alloy via electron beam melting. The results show that the support structures parameters play a significant role in the cost of the applied support and the accuracy of the fabricated object. It was found that with appropriate selection of support design and process parameters, it is possible to reduce the support volume and hence the fabrication cost in metal additive manufacturing (AM). A tooth height of 3 mm, no support offset of 2 mm, and fragmentation separation width of 0.8 mm resulted in lower support volumes without having any effect on the quality of the overhang. This study systematically investigated the support structure design and their outcomes on overhang fabrication. Its conclusions could add value to the researchers working on additive manufacturing of Ti6Al4V alloy by electron beam melting.
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