Wire Arc Additive Manufacturing: A Comprehensive Review and Research Directions.

Over the past years, the demand for the wire arc additive manufacturing (WAAM) is potentially increased, and it has become a promising alternative to subtractive manufacturing. Research reported that the wire arc additively manufactured (WAAMed) material's mechanical properties are comparable to wrought or cast material. In comparison with other fusion sources, WAAM offers a significant cost saving and a higher deposition rate. However, there are significant challenges associated with WAAM such as undesirable microstructures and mechanical properties, high residual stresses, and distortion. Thus, more research is still needed to handle the above challenges by optimizing the process parameters and post-deposition heat treatment. In line with the above, this paper attempts to fill the gap by presenting a comprehensive review of WAAM literature including stagewise development of WAAM, metals and alloys used, effects of process parameters, methodologies used by various researchers to improve the quality of WAAM component. Besides, this work proposes the areas that could be used as avenues for future research. [ABSTRACT FROM AUTHOR]