Research Progress in the Numerical Simulation of Heat and Mass Transfer during Wire Arc Additive Manufacturing

Wire Arc Additive Manufacturing (WAAM), which is able to create large metal components with high deposition rate and low equipment cost, has increasingly attracted attention from industrial sectors, including aerospace, shipbuilding, military equipment etc. During WAAM, the combined effects from arc characteristics, droplet transfer behaviour, molten pool flow and solidification, and heat accumulation under the complex thermal cycle plays a critical role in the deposition formation and quality, which also the theoretical basis of realizing the geometry and material properties in control. The emerging research on the numerical simulation of WAAM is reviewed in this article, and a comprehensive overview of the physical mechanism of WAAM based on different heat sources is also provided. The heat and mass transfer produced in different WAAM process are described to reveal their intrinsic connections. Common defects are depicted, including formation mechanism, inside factors, inhibition strategy. Methods for controlling the deposition process, geometry and quality are discussed, take into account the physical characteristics of WAAM. It is concluded in this paper that many challenges still exist in the numerical simulation of the WAAM process, and critical thinking and suggestions are proposed for its future development and application. © 2024 Chinese Mechanical Engineering Society. All rights reserved.