Integration of direct energy deposition systems with an optimized process planning algorithm

Abstract

Directed Energy Deposition (DED) has gained significant interest from the industrial sectors due to its ability to fabricate medium-to-large scale parts with high productivity and low capital investment. Within DED technologies, DED-Arc stands out as a promising method for practical industrial applications. However, the process planning presents challenges for developing an automated system suitable for industrial use. When preparing large, complex, and multi-feature parts, inappropriate trajectory and process strategies can often result in issues such as poor molding accuracy, lengthy manufacturing cycles, and significant material waste. Overall, there is currently no integrated process planning software for DED that can effectively improve manufacturing efficiency. Knowledge from many disciplines, such as computer science, material engineering, mechanical engineering, and industrial system engineering, is advantageous to develop such a process planning system. The system integrates optimal process parameters with a global path planning methodology, enabling the unified manufacturing of complex components through the synchronization of process, trajectory, parameters, and structure via integrated printing equipment. This paper proposes a composite path that integrates the advantages of the contour offset path and zigzag path, and optimizes the overlap distance through experiments and overlap models to achieve gap-free printing with multiple passes in a single deposition layer. By establishing a geometric model of deposition forming, the influence of multi-layer, multi-pass edge collapse (material shortage regions) on the geometric fidelity of parts is analyzed, and a constraint-compensation path planning method is proposed. Compared with the traditional method, the material utilization rate of the proposed method increases from 80 % to 95.6 %. This significant increase in material utilization rate indicates that the constraint-compensation forming control method is an effective way to reduce material waste and improve the overall efficiency and quality of the additive manufacturing process. This is critical in the development of high-quality, complex parts that require precise and accurate deposition of material layers.