Advancements in Wire Arc Additive Manufacturing of Functionally Graded Materials: Optimizing Compositional Gradients and Mechanical Performance: An Overview

Wire Arc Additive Manufacturing (WAAM) is an advanced 3D metal printing technique that enables the fabrication of complex, large-scale components with minimal material waste. Its ability to control deposition parameters has made it particularly useful for creating Functionally Graded Materials (FGMs), which exhibit a gradual variation in composition and structure. This paper explores recent advancements in the fabrication of FGMs using WAAM, focusing on material combinations, process optimization, and the resulting microstructural and mechanical properties. Through numerical analysis, it was observed that controlling the wire feed rate and deposition speed significantly influences the mechanical properties, including tensile strength and hardness. For instance, increasing the wire feed rate from 2 mm/s to 8 mm/s improved the ultimate tensile strength by 15%, but a further increase led to a 10% reduction due to incomplete fusion between layers. Additionally, post-processing techniques such as laser polishing reduced surface roughness by up to 80%, significantly enhancing the component's performance in wear-sensitive applications. This study highlights the importance of optimizing process parameters and post-processing techniques to enhance the functionality and reliability of FGMs fabricated by WAAM.