Abstract
Strengthening mechanisms from thermomechanical processing treatments were explored in single-phase FCC high-entropy alloy Al0.1CoCrFeNi. Cold work offers substantial strengthening in this low stacking fault energy material owing to the resultant high work hardening rates. An enormous increase in yield strength of ~ 275% was obtained in 40% rolled material, but was accompanied by a steep drop in ductility. Recovery and recrystallization annealing treatments were investigated for improving elongation and obtaining better balance of strength–ductility combinations. Formation of novel microstructures from the different processing routes was examined. X-ray diffraction peak broadening and mechanical test results were coupled to estimate micro-strain in the different conditions and understand micro-strain’s correlation to strength. Retention of large-scale deformation twins formed during cold rolling is shown to play a key role in elevation of yield strength after heat treatments.
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References
M.C. Gao, High-Entropy Alloys, Springer, New York, 2016
J.W. Yeh, Novel Alloy Concept, Challenges and Opportunities of High-Entropy Alloys, Frontiers Design Materials, B. Raj, Ed., CRC Press, Boca Raton, 2007, p 31–47
M.-H. Tsai, High-Entropy Alloys: A Critical Review, Mater. Res. Lett., 2014, 2(3), p 107–123
Y. Zhang, Solid-Solution Phase Formation Rules for Multi-Component Alloys, Adv. Eng. Mater., 2008, 10(6), p 534–538
W.R. Wang, Phases, Microstructure and Mechanical Properties of AlxCoCrFeNi High-Entropy Alloys at Elevated Temperatures, J. Alloys Compd., 2014, 589, p 143–152
W.R. Wang, Effects of Al Addition on the Microstructure and Mechanical Property of AlxCoCrFeNi High-Entropy Alloys, Intermetallics, 2012, 26, p 44–51
J. Joseph, Understanding the Mechanical Behaviour and the Large Strength/Ductility Differences Between FCC and BCC AlxCoCrFeNi High Entropy Alloys, J. Alloys Compd., 2017, 726, p 885–895
H.P. Chou, Microstructure, Thermophysical and Electrical Properties in AlxCoCrFeNi (0 ≤ x ≤ 2) High-Entropy Alloys, Mater. Sci. Eng. B, 2009, 163(3), p 184–189
M. Komarasamy, Effect of Microstructure on the Deformation Mechanism of Friction Stir-Processed Al0.1CoCrFeNi High Entropy Alloy, Mater. Res. Lett., 2015, 3(1), p 30–34
N. Kumar, High Strain-Rate Compressive Deformation Behavior of the Al0.1CrFeCoNi High Entropy Alloy, Mater. Des., 2015, 86, p 598–602
F. Otto, The Influences of Temperature and Microstructure on the Tensile Properties of a CoCrFeMnNi High-Entropy Alloy, Acta Mater., 2013, 61(15), p 5743–5755
A. Gali, Tensile Properties of High- and Medium-Entropy Alloys, Intermetallics, 2013, 39, p 74–78
S. Asgari, Strain Hardening Regimes and Microstructural Evolution During Large Strain Compression of Low Stacking Fault Energy FCC Alloys that Form Deformation Twins, Metall. Mater. Trans. A, 1997, 28(9), p 1781–1795
Y.Z. Tian, Significant Contribution of Stacking Faults to the Strain Hardening Behavior of Cu-15% Al Alloy with Different Grain Sizes, Sci. Rep., 2015, 5, p 16707
G.K. Williamson, X-Ray Line Broadening from Filed Aluminium and Wolfram, Acta Metall., 1953, 1(1), p 22–31
G.K. Williamson, III. Dislocation Densities in Some Annealed and Cold-Worked Metals from Measurements on the X-Ray Debye-Scherrer Spectrum, Philos. Mag., 1956, 1(1), p 34–46
M. Karolus, Crystallite Size and Lattice Strain in Nanocrystalline Ni-Mo Alloys Studied by Rietveld Refinement, J. Alloys Compd., 2004, 367(1-2), p 235–238
S. Kumari, Strain Anisotropy in Freestanding Germanium Nanoparticles Synthesized by Ball Milling, J. Nanosci. Nanotechnol., 2009, 9(9), p 5231–5236
M. Komarasamy, Serration Behavior and Negative Strain Rate Sensitivity of Al0.1CoCrFeNi High Entropy Alloy, Intermetallics, 2017, 84, p 20–24
X. San, Effect of Stacking Fault Energy on Mechanical Properties of Ultrafine-Grain Cu and Cu-Al Alloy Processed by Cold-Rolling, Trans. Nonferr. Met. Soc. China, 2012, 22(4), p 819–824
S.W. Wu, Strong Grain-Size Effect on Deformation Twinning of an Al0.1CoCrFeNi High-Entropy Alloy, Mater. Res. Lett., 2017, 5(4), p 276–283
X.D. Xu, Transmission Electron Microscopy Characterization of Dislocation Structure in a Face-Centered Cubic High-Entropy Alloy Al0.1CoCrFeNi, Acta Mater., 2018, 144, p 107–115
T.H. Courtney, Mechanical Behavior of Materials, Waveland Press, Long Grove, 2005
Acknowledgments
The work was performed under a cooperative agreement between the Army Research Laboratory and the University of North Texas (W911NF-16-2-0189). We also acknowledge the Materials Research Facility at UNT for microscopy facilities.
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Gangireddy, S., Whitaker, D. & Mishra, R.S. Significant Contribution to Strength Enhancement from Deformation Twins in Thermomechanically Processed Al0.1CoCrFeNi Microstructures. J. of Materi Eng and Perform 28, 1661–1667 (2019). https://doi.org/10.1007/s11665-019-3885-1
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DOI: https://doi.org/10.1007/s11665-019-3885-1