Near-circular EDM hole drilling for deterministic cellular lattice structures of LPBF IN718

Additive manufactured (AM) metallic lattice structures are being largely explored for different engineering ap-plications. The fastening, implantation, and installation of such lattice structures demand secondary processing. In the current work, through-hole drilling is performed using electrical discharge machining (EDM) on Inconel 718 (IN718) lattice structures fabricated by laser powder bed fusion (LPBF). The challenges in EDM hole drilling have been encountered and uncertainty in the machined holes owing to periodically open pores and nodes in the lattice structures sizes has been identified. Finally, an experimental strategy has been proposed for near-circular hole drilling by design optimization and tool positioning with respect to the cellular structures.