J. Mater. Sci. Technol. ›› 2020, Vol. 51: 167-172.DOI: 10.1016/j.jmst.2020.02.048

• Research Article • Previous Articles     Next Articles

Toughening FeMn-based high-entropy alloys via retarding phase transformation

Ran Weia, Kaisheng Zhanga, Liangbin Chenb, Zhenhua Hanc, Chen Chena,*(), Tan Wanga,*(), Jianzhong Jiangd, Tingwei Hue, Shaokang Guana, Fushan Lia,*()   

  1. a School of Materials Science and Engineering, Zhengzhou University, Zhengzhou, 450001, China
    b College of Physics and Electronic Engineering, Xinyang Normal University, Xinyang, 464000, China
    c School of Materials Science and Engineering, Xi’an University of Technology, Xi’an, 710048, China;
    d International Center for New-Structured Materials (ICNSM), Laboratory of New-Structured Materials, State Key Laboratory of Silicon Materials, and School of Materials Science and Engineering, Zhejiang University, Hangzhou, 310027, China
    f Key Laboratory of Tropical Translational Medicine of Ministry of Education/School of Tropical Medicine and Laboratory Medicine, Hainan Medical University, Haikou, 571199, China;
  • Received:2020-01-12 Revised:2020-02-03 Accepted:2020-02-17 Published:2020-08-15 Online:2020-08-11
  • Contact: Chen Chen,Tan Wang,Fushan Li

Abstract:

Various high entropy alloys (HEAs) with improved mechanical properties were developed by reducing the phase stability and then promote the phase transformation. The promotion of deformation-induced martensitic transformation from face-centered cubic (fcc) to hexagonal close-packed (hcp) mostly focuses on overcoming the trade-off of strength-ductility of HEAs at room temperature. However, the hcp phase is brittle at cryogenic-temperature, and thus the enhancement of cryogenic ductility of these HEAs still remains a challenge. Here, we present a concept to toughening Fe50Mn30Co10Cr10 HEAs at cryogenic-temperature via retarding phase transformation. The retarded but more persistent phase transformation at high strain level was realized via tailoring the grain size. To further verify the effect of phase transformation rate on ductility of HEAs, the mechanical properties of Fe40Mn40Co10Cr10 HEAs with higher stacking fault energy were tested at room and cryogenic temperature, respectively. The present study sheds light on developing high performance HEAs, especially for alloys with brittle phase transformation products.

Key words: High-entropy alloys (HEAs), Transformation induced ductility, Mechanical properties, Cryogenic temperature