Optimization of Bead Morphology for Cold Metal Transfer Wire Arc Additive Manufacturing of AZ31 Magnesium Alloy Wires

Wire arc additive manufacturingWire Arc Additive Manufacturing (WAAM) (WAAM) is a direct energy deposition additive manufacturing technology used for creating medium to large-scale components. This process involves the deposition of multiple layers of beads to fabricate a component from 3D CAD data. By controlling various process parameters, the fabrication of a component can be achieved through the deposition of multiple beads and layers. Therefore, the selection of suitable process parameters for efficient bead geometry, and bead-on substrate trials were conducted for the magnesium alloyMagnesium alloys (Mg alloys) (AZ31) using Taguchi L9 orthogonal array of experiments and a cold metal transferCold Metal Transfer (CMT) (CMT) T400i welding power source. The input parameters chosen were wireWire feed, arc length correction, and travel speed, while the response parameters chosen were bead width, bead height, wetting angle, and dilution. The results were analyzed using analysis of varianceAnalyzed using analysis of variance (ANOVA) (ANOVA) and regression equations. The R2 and Adj R2 values were both found to be above 90% for all the responses demonstrating the fitness of the model. Mean response optimizationOptimization was employed to optimize the process parameters. To address the conflicting nature of the multiple responses, a Grey relation approach was applied to provide a unique solution for all responses. The validation of optimum process parameters was also conducted to determine the ability and suitability of the Grey relation approach. It was found that the predicted optimum process conditions were feasible settings for multi-layer deposition, with a deviation of less than 5% for experimental trials.