Optimization of the pulsed arc welding parameters for wire arc additive manufacturing in austenitic steel applications

Industrial development continues to present challenges for manufacturers. One of them is additive manufacturing (AM) with metallic materials. One promising solution is wire arc additive manufacturing (WAAM). Currently, WAAM is a more promising tool for developers, firstly due to the simplicity of its realization and secondly for its cost-effectiveness. Building materials are represented by welding wires, so the deposition rate is favorable. A pulse power source is commonly used in this scheme of realization. Much less attention has been paid to the optimization of the power source working regime, i.e., welding mode. Indeed, the power determines the whole process of WAAM. Therefore, in the present work, an attempt has been made to perform a scientifically based design for the optimal welding mode. The austenitic welding wire was chosen to eliminate phase-transition effects in the solid state of the deposited metal. As a result of the investigation, the advantages of the designed welding mode for WAAM application are made clear. It was shown that the predominant effect on penetration depth possesses pulse current and its input is 49%, while other parameters, i.e., pause current, pulse on time, and frequency, have a less valuable impact. The Taguchi optimization algorithm allowed the development of a specific welding mode for providing better formation of the welds, more grain fined microstructure, and thus improved properties of the modeled wall. Successful efforts have been made to optimize welding modes for WAAM applications. This study is important for manufacturers as well as engineers and scientists.