Fabrication and Characterization of Nickel-Aluminide Cladding by Dual-Wire Arc Additive Manufacturing

Nickel aluminide is a widely utilized intermetallic compound, prized for its high strength, low density, and resistance to both corrosion and creep. This study investigates the impact of heat input during the fabrication of nickel-aluminide intermetallic compounds using the dual-wire gas tungsten arc welding process. The results indicate that an increase in clad layer dilution from 28.9% to 33.4% reduces the amount of aluminum in the molten pool from 32.46 to 21.96 wt% while increasing the presence of the Ni3Al phase. Additionally, the NiAl phase decreases when moving from the upper side of the coating to the fusion line. When the arc current is increased from 110 to 150 A, a coarse dendritic structure forms, and the dendritic arms increase from 2.6 +/- 0.4 to 5.5 +/- 0.3 mu m. This increase in current also results in yield strength and tensile strength values of 500.21 +/- 14.56 and 752.32 +/- 25.12 MPa, respectively, representing decreases of 15.2% and 5.1%. Furthermore, as the arc current increases from 110 to 150 A, both the friction coefficient and the wear rate increase to 0.43 and 0.29 +/- 0.02 mu g m-1, respectively. However, corrosion resistance improves by 66.3%. Given the unique characteristics of nickel aluminide, the fabrication of in situ nickel aluminide is being investigated through electric arc-based additive manufacturing herein. When in situ nickel aluminide is fabricated using the dual-wire arc welding process and compared to a low carbon steel substrate, there is an observed increase in hardness and wear resistance by 266% and 88%, respectively.image (c) 2024 WILEY-VCH GmbH