Imperial College London
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ProfessorDavidDye

Faculty of Engineering, Department of Materials

Professor of Metallurgy
 
 
 
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Contact

 

+44 (0)20 7594 6811david.dye

 
 
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Location

 

1.09GoldsmithSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Wang:2018:10.1016/j.actamat.2018.05.013,
author = {Wang, Y and Liu, B and Yan, K and Wang, M and Kabra, S and Chiu, Y-L and Dye, D and Lee, PD and Liu, Y and Cai, B},
doi = {10.1016/j.actamat.2018.05.013},
journal = {Acta Materialia},
pages = {79--89},
title = {Probing deformation mechanisms of a FeCoCrNi high-entropy alloy at 293 and 77 K using in situ neutron diffraction},
url = {http://dx.doi.org/10.1016/j.actamat.2018.05.013},
volume = {154},
year = {2018}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - The deformation responses at 77 and 293K of a FeCoNiCr high-entropy alloy, produced by a powder metallurgy route, are investigated using in situ neutron diffraction and correlative transmission electron microscopy. The strength and ductility of the alloy are significant improved at cryogenic temperatures. The true ultimate tensile strength and total elongation increased from 980MPa to 45% at 293K to 1725MPa and 55% at 77K, respectively. The evolutions of lattice strain, stacking fault probability, and dislocation density were determined via quantifying the in situ neutron diffraction measurements. The results demonstrate that the alloy has a much higher tendency to form stacking faults and mechanical twins as the deformation temperature drops, which is due to the decrease of stacking fault energy (estimated to be 32.5mJ/m2 and 13mJ/m2 at 293 and 77K, respectively). The increased volume faction of nano-twins and twin-twin intersections, formed during cryogenic temperature deformation, has been confirmed by transmission electron microscopy analysis. The enhanced strength and ductility at cryogenic temperatures can be attributed to the increased density of dislocations and nano-twins. The findings provide a fundamental understanding of underlying governing mechanistic mechanisms for the twinning induced plasticity in high entropy alloys, paving the way for the development of new alloys with superb resistance to cryogenic environments.
AU  - Wang,Y
AU  - Liu,B
AU  - Yan,K
AU  - Wang,M
AU  - Kabra,S
AU  - Chiu,Y-L
AU  - Dye,D
AU  - Lee,PD
AU  - Liu,Y
AU  - Cai,B
DO  - 10.1016/j.actamat.2018.05.013
EP  - 89
PY  - 2018///
SN  - 1359-6454
SP  - 79
TI  - Probing deformation mechanisms of a FeCoCrNi high-entropy alloy at 293 and 77 K using in situ neutron diffraction
T2  - Acta Materialia
UR  - http://dx.doi.org/10.1016/j.actamat.2018.05.013
UR  - http://hdl.handle.net/10044/1/59902
VL  - 154
ER  -
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