Manipulating the ordered oxygen complexes to achieve high strength and ductility in medium-entropy alloys

Oxygen solute strengthening is an effective strategy to harden alloys, yet, it often deteriorates the ductility. Ordered oxygen complexes (OOCs), a state between random interstitials and oxides, can simultaneously enhance strength and ductility in high-entropy alloys. However, whether this particula...

Full description

Saved in:
Bibliographic Details
Published in:Nature communications 2023-02, Vol.14 (1), p.806-806, Article 806
Main Authors: Jiao, Meiyuan, Lei, Zhifeng, Wu, Yuan, Du, Jinlong, Zhou, Xiao-Ye, Li, Wenyue, Yuan, Xiaoyuan, Liu, Xiaochun, Zhu, Xiangyu, Wang, Shudao, Zhu, Huihui, Cao, Peipei, Liu, Xiongjun, Zhang, Xiaobin, Wang, Hui, Jiang, Suihe, Lu, Zhaoping
Format: Article
Language:English
Subjects:
147/135
147/137
147/143
639/301/1023/1026
639/301/1023/303
Alloy systems
Alloys
Ductility
Entropy
Grain Boundary Segregation
High entropy alloys
Humanities and Social Sciences
Interstitials
Medium entropy alloys
multidisciplinary
Niobium
Oxygen
Phase stability
Science
Science (multidisciplinary)
Strengthening
Yield strength
Zirconium
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Oxygen solute strengthening is an effective strategy to harden alloys, yet, it often deteriorates the ductility. Ordered oxygen complexes (OOCs), a state between random interstitials and oxides, can simultaneously enhance strength and ductility in high-entropy alloys. However, whether this particular strengthening mechanism holds in other alloys and how these OOCs are tailored remain unclear. Herein, we demonstrate that OOCs can be obtained in bcc (body-centered-cubic) Ti-Zr-Nb medium-entropy alloys via adjusting the content of Nb and oxygen. Decreasing the phase stability enhances the degree of (Ti, Zr)-rich chemical short-range orderings, and then favors formation of OOCs after doping oxygen. Moreover, the number density of OOCs increases with oxygen contents in a given alloy, but adding excessive oxygen (>3.0 at.%) causes grain boundary segregation. Consequently, the tensile yield strength is enhanced by ~75% and ductility is substantially improved by ~164% with addition of 3.0 at.% O in the Ti-30Zr-14Nb MEA. Ordered oxygen complexes (OOCs) endow a unique interstitial strengthening mechanism for simultaneously enhancing strength and ductility in HEAs. Here, the authors demonstrate whether such mechanism can be extended to other alloy systems and how the formation of OOCs is tailored.
ISSN:2041-1723
2041-1723
DOI:10.1038/s41467-023-36319-0