Single Layer Formation of Plasma Based Wire Arc Additive Manufacturing

Wire and Arc Additive Manufacturing (WAAM) process is relatively a new approach to 3D metal printing technology. The process is capable of producing complex parts directly from 3D computer-aided design data by utilizing normal welding equipment. Gas metal arc welding, gas tungsten arc welding, and plasma arc welding are three different types of heat sources commonly used in WAAM to melt the welding wire. This approach is primarily different from the normal arc welding which is used to join materials. This is because in WAAM, materials are deposited layer by layer consecutively until a 3D structure is produced. In this study, the WAAM process is based on plasma arc welding. The study explores the effect of the processing parameters using a full factorial approach. Through the combination of these parameters, different types of deposition have been observed. These are little deposition, droplet deposition, discontinuous deposition and continuous deposition. The last one can be obtained at a specific combination of stand-off distance, speed and current. The recommended optimal parameters can produce the first layer, which is characterized by the continuous single-track formation. Continuous deposition is essential in WAAM as it is the foundation for producing a good 3D structure during layer-by-layer deposition.