Optimization of L-DED Parameters for AlMo0.5NbTa0.5TiZr Based on Response Surface Methodology

To investigate the impact of process parameters on the deposition morphology of AlMo_0.5NbTa_0.5TiZr refractory high-entropy alloy during laser directional energy deposition, mathematical models were constructed for laser power, scanning rate, powder feeding rate and dilution rate, aspect ratio, and deposition area. These models were developed using the response surface method, and multi-objective optimization was conducted using the NSGA-II genetic algorithm. The results demonstrate that the optimal process parameters are laser power of 1150.08 W, scanning rate of 436.23 mm/s, and powder feeding rate of 2.81 g/min. The errors between the actual and predicted results for the dilution rate, aspect ratio, and deposition area are 6.5, 7.25, and 6.45%, respectively. These findings validate the efficacy of the multi-objective optimization of NSGA-II and the model's reliability. The findings of this study provide a theoretical framework for predicting and controlling the morphology of the deposited layer of refractory high-entropy alloy.