Wire arc additive manufacturing of nanomodified 2024 alloy

In this study, nanomodified 2024 filler metal is investigated for WAAM applications based on CMT-PADV arc welding technology. Al-Cu series alloys are usually considered non weldable since they are highly susceptible to hot cracking and usually show high porosity. In this paper it has been demonstrated that the addition of TiC nanoparticles to the wire enhances nucleation during liquid to solid transformation, reducing the grain size and segregation and obtaining as a result a fine equiaxed microstructure which is free of cracks and with a very low residual porosity. Obtained microstructure contributed to achieve high isotropic mechanical properties after heat treatment with yield stress above 370 MPa, tensile strength higher than 450 MPa and more than 4% of elongation. These mechanical properties are considered very balanced and suitable for the manufacturing of structural aluminium components by WAAM.