Holden Hyer, Le Zhou, Sharon Park, Thinh Huynh, Abhishek Mehta, Saket Thapliyal, Rajiv S. Mishra, Yongho Sohn

Using the calculation of phase diagrams approach and Scheil solidification modeling, the Al-2.5Mg-1.0Ni-0.4Sc-0.1Zr alloy was designed, intentionally with an extraordinarily high cracking susceptibility, making it prime for solidification cracking during laser powder bed fusion. This study demonstrates the ability to mitigate even the most extreme solidification cracking tendencies in aluminum alloys with only minor alloying additions of Sc and Zr, 0.5 wt.% max. Furthermore, by employing a simple direct ageing heat treatment, good tensile mechanical properties were observed with a yield strength of 308 MPa, an ultimate tensile strength of 390 MPa, and a total elongation of 11%.

Keywords: Additive manufacturing; Cracking susceptibility; Aluminum alloy; CALPHAD; Mechanical properties

Journal of Materials Science & Technology
Volume 103, 2022, Pages 50-58, ISSN 1005-0302

https://doi.org/10.1016/j.jmst.2021.06.023

(https://www.sciencedirect.com/science/article/pii/S1005030221006526)