Wire Arc Additive Manufacturing (WAAM): Reviewing Technology, Mechanical Properties, Applications and Challenges

Manufacturing sector is adopting additive manufacturing-based techniques due to their ability to manufacture complex near net shapes functional parts using layer by layer deposition. In addition, manufacturing sector is impressed by the potential of 3D printing and additive manufacturing due to its disruptive nature and ability to revolutionize the product development. The advancements in additive manufacturing are not only limited to the process level, but also different difficult to machine materials can also be printed with exceptional mechanical characteristics and related lattice structure. The concept of wire arc additive manufacturing was introduced in early 1920, when idea to use an electronic arc with filler wires as a source of heat to deposit metal was investigated. However, in the last decade a lot of effort has been performed in this field. Today, it is used as a reliable source of additive manufacturing due to various advantages it provides over other additive manufacturing processes. One of the major advantages of the wire arc additive manufacturing method is that it reduces the manufacturing time by 40-60% and the post-processing time by 15-20%. It is being used for making landing gears in the aerospace industry. The manufacturers save about 78% of the raw material in comparison to the subtractive manufacturing that was used before.

There is a possibility to manufacture different intricate geometrics that cannot be produced through conventional processes previously. The conventional design concepts such as design for manufacture (DFM) and design for assembly (DFA) have been modified and simplified. Wire arc additive manufacturing has emerged as one of the leading additive manufacturing processes due to its high deposition rate and economic feasibility. A lot of progress has been made to understand and improve this process and the mechanical properties associated with the fabricated parts. It is specifically cheaper to print large-scale metallic components using wire arc additive manufacturing. This paper gives a thorough review of the work that has been done on wire arc additive manufacturing by comparing different technological variants of wire arc additive manufacturing, which include Metal Inert Gas (MIG), Tungsten Inert Gas (TIG) and Plasma Arc Welding (PAW). The study also discusses the mechanical properties of the fabricated components using different metals, the defects and challenges the process faces today and how they can be reduced. In the end the study also provides overview of wire arc additive manufacturing applications in some of the industrial sectors such as construction, automotive, and structural etc.