Investigations and Optimization of Cold Metal Transfer-based WAAM Process Parameters for Fabrication of Inconel 718 Samples using Response Surface Methodology

This article outlines techniques for optimizing input parameters for the welding process, such as welding current, speed, and gas flow rate in relation to weld bead geometry and Dilution, using Response Surface Methodology (RSM). In the wire arc additive manufacturing (WAAM) process, single-weld bead stability and quality play a prominent role in the final manufactured part's quality and shape. A single-bead geometry model was initially established using RSM, and experiments were carried out using a central composite design of experiments for depositing Inconel 718 in WAAM. The design factors and responses were analyzed using multiple regression equations, and the validity of the resulting regression equations was evaluated using ANOVA. The researchers fabricated a multi-layer structure with optimal parameters, including a welding current of 210 A, 6.91 mm/s speed, and a gas flow rate of 25 l/min. Optical microscopy characterized the microstructures, revealing small dendritic grains in the top layer, equiaxed in the middle and side regions, and columnar in the lower region. The current study benefits industrial applications for developing the Inconel 718 superalloy WAAM structure.