Five-axis hybrid manufacturing with DED and milling for complex multi-branched metallic parts

Hybrid manufacturing (HM), by combining metal additive manufacturing (AM) and subtractive machining (SM) on a single platform, allows the manufacturing of complex metallic parts with high dimensional accuracy and surface quality, which originally were impossible to manufacture solely by either AM or SM. The key to HM is to plan an optimal AM/SM sequence with a minimal number of alternations while satisfying both the machinable and printable constraints. In this paper, a continuous five-axis HM sequence planning method is proposed for LP-DED in which all the building direction, nozzle axis and cutter axis are allowed to change continuously. Firstly, a guide curve-based model partition method is proposed to decompose a given multi-branched model into a set of blocks, each of which is adaptively sliced into a series of high-quality non-parallel planar layers, conforming to the AM manufacturing characteristics. Secondly, a beam-guided downward expansion algorithm is proposed to search for the optimal HM segments by evaluating each layer’s five-axis printability and machinability, each of which will be first printed and then machined subsequently. Physical experiments of five test models are performed on a homebuilt five-axis hybrid manufacturing center, whose results verify the feasibility and capabilities of the proposed methodology.