| Abstract Scope |
Hybrid directed energy deposition (DED) integrated with interlayer milling offers a promising strategy to improve geometric accuracy, process stability, and structural integrity in metal additive manufacturing. This study investigates the hybrid process through a combined experimental and simulation-based framework. On the experimental side, real-world DED trials are performed to identify practical process recipes for reducing geometry defects and improving bead formation. Particular attention is given to process-start behavior and parameter combinations that promote stable liquid-bridge formation, thereby mitigating material-deposition delay and early-stage geometric inconsistency. On the simulation side, a unified thermo–mechanical finite element framework is developed to analyze residual stress evolution throughout the hybrid DED–milling process. A solver-specific implementation is developed and, for the first time, deployed on the Siemens NX platform. Numerical case studies systematically investigate residual stress formation during deposition, stress redistribution caused by interlayer milling, and the effects of milling frequency and bead removal order on final stress distribution. The results reveal characteristic stress evolution trends, including tensile stress migration during deposition and threshold-like sensitivity to milling frequency. |