Topology optimisation for large-scale wire-arc directed energy deposition considering environmental impact and cost

Abstract

Advancements in wire-arc directed energy deposition (DED) have created new opportunities for manufacturing efficient large-scale structures. While wire-arc DED is often viewed as more sustainable and economical due to the potential of producing lighter structures, its higher environmental impact and cost per unit of weight necessitate further considerations during the design phase. This paper explores how sustainability and cost can be integrated into conceptual design through topology optimisation. The approach is demonstrated through a case study, including a parametric study on specific environmental impact and the cost of wire-arc DED versus CM, applicable to current data and future estimates. Findings indicate that beams manufactured solely with wire-arc DED are sensitive to fluctuations in specific environmental impact and cost of wire-arc DED, potentially losing their material saving advantage. Conversely, hybrid beams that combine conventional profiles with wire-arc DED offer a better balance between structural performance, sustainability and economic feasibility.