Effect of arc oscillation on porosity and mechanical properties of 2319 aluminum alloy fabricated by CMT-wire arc additive manufacturing

In this paper, arc oscillation is applied in the fabrication of 2319 aluminum alloy samples by cold metal transition wire arc additive manufacturing process (CMT-WAAM). The porosity, microstructure and mechanical properties of 2319 aluminum alloy under different arc oscillation patterns were discussed. The results showed that the stirring of arc oscillation can influence the molten pool shape and improve the fluidity, change the thermal distribution and the growth direction of columnar crystal. Arc oscillation has a obvious effect on reducing the grain size and proportion of pores. After using the spiral arc oscillation pattern and asymmetrical trapezoid arc oscillation pattern, the volume fraction of pores reduced from 2.64% to 1.09% and 1.22%, and the size of pores was mainly smaller than 40 mm, respectively. The tensile strength in vertical direction and plasticity were improved with arc oscillation, but its effect on the horizontal tensile strength was not noticeable. After solid solution-aging treatment, the tensile strength of the sample with spiral arc oscillation pattern increased to 277 MPa, with a cross-section reduction of 3.6%.& COPY; 2023 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Automated summary

This paper discusses the influence of arc oscillation on the porosity, microstructure, and mechanical properties of 2319 aluminum alloy samples. The results show that arc oscillation can improve the shape of the molten pool, enhance fluidity, and change the thermal distribution and growth direction of columnar crystals, thereby reducing grain size and pore proportion. After using spiral arc oscillation and asymmetrical trapezoid arc oscillation patterns, the volume fraction of pores decreased to 1.09% and 1.22%, respectively, and the size of pores was mainly smaller than 40 mm. Arc oscillation improved the tensile strength and plasticity in the vertical direction, but its effect on horizontal tensile strength was not significant. After solid solution-aging treatment, the tensile strength of the sample with spiral arc oscillation pattern increased to 277 MPa, with a cross-section reduction of 3.6%.