Comparative study on forming approaches in directed energy deposition of inclined thin-walled structures

Considering the complex geometric characteristics of inclined thin-walled parts (e.g., variable curvature and angle), the forming process of inclined thin-walled parts (e.g., blades) by directed energy deposition (DED) often remains problems, such as collapse and surface powder adhesion. Therefore, the paper adopts a combination of theoretical and experimental methods to analyze the forming quality of inclined thin-walled parts. Firstly, the force analysis of powder in DED under unsupported conditions is explored, and the effects of powder gravity and viscous force on the processing of inclined thin-walled parts are determined. Then, the influence of inclined angle, curvature and scanning paths on the forming height and accuracy of thin-walled parts was analyzed in the study, and a method of preset inclined angle was proposed to improve the inclined angle during DED. Finally, the mechanical properties (tensile strength and hardness) of inclined thin-walled parts were investigated in the paper, achieving efficient and high-precision deposition of inclined thin-walled parts. This also provides a theoretical basis and reference for the future use of DED to form complex surfaces.