Additive manufacturing has revolutionized the manufacturing paradigm in recent years due to the possibility of creating complex shaped three-dimensional parts which can be difficult or impossible to obtain by conventional manufacturing processes. Among the different additive manufacturing techniques, wire and arc additive manufacturing (WAAM) is suitable to produce large metallic parts owing to the high deposition rates achieved, which are significantly larger than powder-bed techniques, for example. The interest in WAAM is steadily increasing, and consequently, significant research efforts are underway. This review paper aims to provide an overview of the most significant achievements in WAAM, highlighting process developments and variants to control the microstructure, mechanical properties, and defect generation in the as-built parts; the most relevant engineering materials used; the main deposition strategies adopted to minimize residual stresses and the effect of post-processing heat treatments to improve the mechanical properties of the parts. An important aspect that still hinders this technology is certification and nondestructive testing of the parts, and this is discussed. Finally, a general perspective of future advancements is presented.

Current Status and Perspectives on Wire and Arc Additive Manufacturing (WAAM)

Although wire arc additive manufacturing (WAAM) has proven its capability of fulfilling demands of production of medium-to-large-scale components for automotive and allied sectors made up of alumin...

A review of wire arc additive manufacturing and advances in wire arc additive manufacturing of aluminium

Wire and arc additive manufacturing : Opportunities and challenges to control the quality and accuracy of manufactured parts

Wire arc additive manufacturing (WAAM) is steadily increasing with significant research work are underway. The ability of WAAM to manufacture a large-scale product at a lower cost and shorter lead times has increased its development. The efficiency or potential of WAAM to become a new lead in the additive manufacturing industry is believed to be realized by a few factors. High efficiency and performance require a higher metal deposition rate, which implies higher heat input that negatively affects the manufacturing process. This paper review works for factors associated with heat input on the WAAM process. The factor affecting these properties were explained to identify the optimized WAAM process in terms of heat input. The paper focuses on the impact of heat input on the macrostructure, microstructure and mechanical properties of the parts deposited in the WAAM process. This review also discussed the effect of heat input used by eight different types of arc welding technologies, with appropriate use of wire materials. The study also highlights that heat input affected the microstructure of the WAAM, causing significant changes in grain structure, grain size and pore area percentage. Besides, it can be suggested that grain structure has a strong influence on the WAAM materials' mechanical properties.

J.L. Prado-Cerqueira

Papers

Preliminary development of a Wire and Arc Additive Manufacturing system (WAAM)