**2. Welding processes for additive manufacturing**

The WAAM generally requires a welding process giving high deposition rates without quality and size limitations so that WAAM could become the best alternative for conventional AM processes, especially when dealing with medium and large size component fabrication. The increasing interest over the world in WAAM is mainly because of the advances in robotic controls and modern electronic control circuit systems for different welding machines [10]. The modern methods of controlled short arc processes with reduced heat input like a process called Cold Metal Transfer (CMT) technology were particularly developed for GMAW process and now has been developed by Fronius International, a company works worldwide especially for the WAAM in the name of CMT based GMAW. Tungsten Inert Gas (TIG) welding process and Plasma Arc Welding (PAW) process could be used due to the separation of mass and energy input. Also, apart from the standard welding processes, laser-assisted welding has also been available for this type of AM. The following welding processes have been experimented especially for fabrication worldwide with the focus on the best fabrication practice for fabricating the stainless steel components by WAAM [11].

