@misc{hecht_microstructure_evolution_2023, author={Hecht, U., Vayyala, A., Barriobero-Vila:, P., Navaeilavasani, N., Gain, S., Cazic, I., Mayer, J.}, title={Microstructure evolution in the hypo-eutectic alloy Al0.75CrFeNi2.1 manufactured by laser powder bed fusion and subsequent annealing}, year={2023}, howpublished = {journal article}, doi = {https://doi.org/10.1016/j.msea.2022.144315}, abstract = {The hypo-eutectic medium entropy alloy Al0.75CrFeNi2.1 was processed by laser powder bed fusion (LPBF). The off-equilibrium solidification conditions prohibited coupled eutectic growth. Instead, the primary face centered cubic phase A1(FCC) solidified with a cellular morphology and the body centered, initially ordered B2(BCC) phase formed as a thin intercellular envelope. During post-build annealing an ultrafine quasi-lamellar pattern evolved following BCC growth and coarsening. The novel solid state transformation from cellular to lamellar morphology was attributed to a pronounced anisotropy of the FCC|BCC phase boundary energy. Microstructure evolution was also studied during continuous heating using in situ high-energy synchrotron X-ray diffraction (HEXRD) carried out at the beamline P07-HEMS of PETRA III (German Electron Synchrotron, DESY). The ultrafine and nano-scale features of the microstructure were quantitatively analyzed by atom probe tomography (APT) in the as-built condition and after isothermal annealing at 950 °C. The benefits of LPBF processing were discussed on the basis of mechanical properties measured by 3-point bending. The estimated tensile properties after annealing at 950 °C/6 h reached YS ≈ 860 MPa, UTS ≈1384 MPa with an elongation at fracture of ≈11%. Tensile properties in the as-built condition were comparable to martensitic steels.}, note = {Online available at: \url{https://doi.org/10.1016/j.msea.2022.144315} (DOI). Hecht, U.; Vayyala, A.; Barriobero-Vila:, P.; Navaeilavasani, N.; Gain, S.; Cazic, I.; Mayer, J.: Microstructure evolution in the hypo-eutectic alloy Al0.75CrFeNi2.1 manufactured by laser powder bed fusion and subsequent annealing. Materials Science and Engineering: A. 2023. vol. 862, 144315. DOI: 10.1016/j.msea.2022.144315}}