Dislocation mechanisms and 3D twin architectures generate exceptional strength-ductility-toughness combination in CrCoNi medium-entropy alloy

Zijiao Zhang, Hongwei Sheng, Zhangjie Wang, Bernd Gludovatz, Ze Zhang, Easo P. George, Qian Yu (), Scott X. Mao () and Robert O. Ritchie ()
Additional contact information
Zijiao Zhang: Center of Electron Microscopy & State Key Laboratory of Silicon Materials, Zhejiang University
Hongwei Sheng: George Mason University
Zhangjie Wang: Xi’an Jiaotong University
Bernd Gludovatz: Lawrence Berkeley National Laboratory
Ze Zhang: Center of Electron Microscopy & State Key Laboratory of Silicon Materials, Zhejiang University
Easo P. George: Oak Ridge National Laboratory
Qian Yu: Center of Electron Microscopy & State Key Laboratory of Silicon Materials, Zhejiang University
Scott X. Mao: Center of Electron Microscopy & State Key Laboratory of Silicon Materials, Zhejiang University
Robert O. Ritchie: Lawrence Berkeley National Laboratory

Nature Communications, 2017, vol. 8, issue 1, 1-8

Abstract: Abstract Combinations of high strength and ductility are hard to attain in metals. Exceptions include materials exhibiting twinning-induced plasticity. To understand how the strength-ductility trade-off can be defeated, we apply in situ, and aberration-corrected scanning, transmission electron microscopy to examine deformation mechanisms in the medium-entropy alloy CrCoNi that exhibits one of the highest combinations of strength, ductility and toughness on record. Ab initio modelling suggests that it has negative stacking-fault energy at 0K and high propensity for twinning. With deformation we find that a three-dimensional (3D) hierarchical twin network forms from the activation of three twinning systems. This serves a dual function: conventional twin-boundary (TB) strengthening from blockage of dislocations impinging on TBs, coupled with the 3D twin network which offers pathways for dislocation glide along, and cross-slip between, intersecting TB-matrix interfaces. The stable twin architecture is not disrupted by interfacial dislocation glide, serving as a continuous source of strength, ductility and toughness.

Date: 2017
References: Add references at CitEc
Citations: View citations in EconPapers (4)

Downloads: (external link)
https://www.nature.com/articles/ncomms14390 Abstract (text/html)

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:nat:natcom:v:8:y:2017:i:1:d:10.1038_ncomms14390

Ordering information: This journal article can be ordered from
https://www.nature.com/ncomms/

DOI: 10.1038/ncomms14390

Access Statistics for this article

Nature Communications is currently edited by Nathalie Le Bot, Enda Bergin and Fiona Gillespie

More articles in Nature Communications from Nature
Bibliographic data for series maintained by Sonal Shukla () and Springer Nature Abstracting and Indexing ().