Effect of heat treatment on mechanical and corrosion properties of an Al0.8CrFe2Ni2 alloy processed by laser powder bed fusion

• Published in: Journal of alloys and compounds 2023-08, Vol.953, p.169816, Article 169816
• Main Authors: Vogiatzief, D., Evirgen, A., Pedersen, M., Czerski, J., Mitoraj-Królikowska, M., Godlewska, E., Eshed, E., Hecht, U.
• Format: Article
• Language: English
• Subjects: Corrosion; Laser processing; Mechanical properties; Metals and alloys; Nanostructured materials; Powder metallurgy
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2023.169816

This study presents an Al0.8CrFe2Ni2 high entropy alloy processed by laser powder bed fusion using prealloyed powder. Heat treatment of the near-single-phase face-centered-cubic microstructure, found in the as-built material, led to a fine dual-phase microstructure consisting of face-centered-cubic grains and Al-, Ni-rich body-centered-cubic B2 precipitates. Microstructure characterization, mechanical and corrosion testing revealed the effect of heat treatment on the properties of the novel alloy. The results suggested that tailoring the mechanical properties is possible with heat treatment, by controlling the precipitate size. Refinement of the precipitates led to enhanced strength without significant ductility loss. Corrosion tests in 3.5 % NaCl solution showed that the as-built samples provided an overall better corrosion resistance when compared to heat-treated samples. The presence of the precipitates enhanced the formation of micro-galvanic cells and influenced the corrosion behavior of the alloy in the heat-treated condition. •LPBF processing of a novel Al0.8CrFe2Ni2 HEA using prealloyed powder, leading to a near-single-phase FCC microstructure.•Alloy characterization in as-built condition and after different heat treatments that led to dual-phase FCC-BCC B2 microstructures.•Tailoring of the mechanical properties through the control of the BCC B2 precipitate size with heat treatment.•Variation of the electrochemical properties with respect to the obtained microstructure and BCC B2 precipitate size.