Effects of Nb additions on the microstructure and mechanical property of CoCrFeNi high-entropy alloys

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalpeer-review

159 Scopus Citations
View graph of relations

Author(s)

  • W. H. Liu
  • J. Y. He
  • H. L. Huang
  • H. Wang
  • Z. P. Lu

Detail(s)

Original languageEnglish
Pages (from-to)1-8
Journal / PublicationIntermetallics
Volume60
Online published24 Jan 2015
Publication statusPublished - May 2015

Abstract

A series of five-component CoCrFeNiNbx high entropy alloys (HEAs) were synthesized to investigate alloying effects of the large atom Nb on the structure and tensile properties. Microstructures of these alloys were examined using scanning electron microscopy and the phase evolution was characterized and compared using the ΔHmix-δ and ΔX criteria. It was found that the microstructure changes from the initial single face-centered cubic (FCC) to duplex FCC plus hexagonal close-packed (HCP) structure with additions of Nb. The current alloy system exhibits a hypoeutectic structure and the volume fraction of the Nb-enriched Laves phase with the HCP structure increases with increasing the Nb content, which is mainly responsible for the increment in the yield and fracture strength. Particularly, the Nb0.155 alloy containing a 9.3% Nb-enriched Laves phase exhibits the most promising mechanical properties with the yield strength and plastic strain as high as 321 MPa and 21.3%, respectively. The ΔHmix-δ criteria well describe the phase selection for the thermally treated alloys, while the physical parameter ΔX fails to predict the appearance of the Nb-enriched Laves phase in this alloy system.

Research Area(s)

  • A.High-entropy alloys, B.Phase stability, D.Microstructure, E.Mechanical properties

Citation Format(s)

Effects of Nb additions on the microstructure and mechanical property of CoCrFeNi high-entropy alloys. / Liu, W. H.; He, J. Y.; Huang, H. L.; Wang, H.; Lu, Z. P.; Liu, C. T.

In: Intermetallics, Vol. 60, 05.2015, p. 1-8.

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalpeer-review