Wire Arc Additive Manufacturing (WAAM) is developing rapidly inrecent years due to its advantages, such as higher productivity, lower cost,acceptable quality, and the availability of advanced welding processes. Cold MetalTransfer (CMT), as the most well-known Gas Metal Arc Welding (GMAW) process,is widely used in WAAM. The uniqueness of CMT lies in minimizing the heat inputof the process. However, there is a drawback to the lower heat input, impacting thequality of the geometry of the welding bead, sharp transitions at the weld toe,inclusions, etc., particularly for higher alloyed steel, e.g., tool steel. In this study,two processes were employed: CMT and Pulse Multi Control (PMC). Two types ofshielding gases were used, namely 2% CO2 + 98% Ar and 20% CO2 + 80% Ar.Two levels of wire feed speed were selected: high and low levels. A full-fractionfactorial experimental matrix was created, and bead-on-plate samples wereproduced with different GMAW processes, i.e., CMT and PMC. The geometry ofthe bead-on-plate, including penetration, bead width and height, and toe angle, wasevaluated and analyzed. A correlation between the process factors (shielding gas,type of process, and wire feed speed) and the geometry of the bead was analyzedand determined. A protocol is proposed based on the study results for the selectionof WAAM processes.
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