A Review on Wire and Arc Additive Manufacturing (WAAM)

Modern industry is constantly seeking new investigations and findings in innovative technologies, particularly in the aerospace sector, which is projected to require approximately twenty million tonnes of raw material in the next two decades due to its reliance on titanium with a high buy-to-fly ratio, leading to low material utilization. Traditional machining of metal, particularly in its solid form, results in significant material waste, necessitating the exploration of alternative manufacturing methods. One feasible solution is the integration of additive manufacturing (AM) technologies, which compose motion systems, feedstocks, and energy sources to enable material deposition. While AM predominantly utilizes polymer materials, the potential for employing metals is hindered by their necessity for powdered form and resultant porosity of the final products. Wire and Arc Additive Manufacturing (WAAM) emerges as a viable technology that overcomes these limitations by using metal welding wire as feedstock and electric arc as a heat source, thereby combining welding with AM. This review discusses the advantages of WAAM, including cost-effectiveness compared to conventional AM technologies requiring specialized equipment, and highlights its evolution and significance in addressing modern manufacturing challenges.