Qiao, L., Ramanujan, R. V., & Zhu, J. (2023). Discovery of new Fe2Ni2CrAlx multi-principal element alloys with promising mechanical properties. Journal of Materials Research and Technology, 24, 3996–4008. https://doi.org/10.1016/j.jmrt.2023.04.015
Abstract:
Thermodynamic calculations were utilized to accelerate the pace of discovering promising composition combination by tailoring
phase fraction. Then a family of Fe2Ni2CrAlx multi-principal element alloys (MPEAs) were synthesized to investigate the effect of
Al on the crystal structure, microstructural evolution, and mechanical properties. A two-phase, face-centered cubic (FCC) and bodycentered
cubic (BCC), structure was identified in alloys with lower Al content (x=0.9 and 1.1), the alloy consists of structure with
stripe patterns. As the Al concentration increased, the FCC phases disappeared, the volume fraction of BCC and B2 phase increased.
The morphology turned into polygonal grains in which the periodic maze-shaped microstructure can be identified. Higher Al content
dramatically increased the nanohardness and strength of the Fe2Ni2CrAlx MPEAs, but reduced the plasticity. Among the developed
alloys, the Fe2Ni2CrAl1.2 alloy displayed the best property combination, with yield stress, compressive strength, and plasticity of
1117.8 MPa, 2961MPa and 42.3%. These values are superior to most reported as-cast MPEAs. Precipitation strengthening was
found to be the main strengthening mechanism responsible for the enhanced mechanical properties of the Fe2Ni2CrAl1.2 alloy.
The current work offers the systematic understanding of the strengthening.
License type:
Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0)
Funding Info:
This research / project is supported by the Agency for Science, Technology and Research - Structural Metal Alloys Programme
Grant Reference no. : A18B1b0061
This research / project is supported by the Agency for Science, Technology and Research - AME Programmatic Fund
Grant Reference no. : A1898b0043