J. Mater. Sci. Technol. ›› 2021, Vol. 77: 187-195.DOI: 10.1016/j.jmst.2020.10.052

• Research Article • Previous Articles     Next Articles

The relationship between thermo-mechanical history, microstructure and mechanical properties in additively manufactured CoCrFeMnNi high entropy alloy

Hongge Lia, Yongjiang Huanga,*(), Jianfei Suna, Yunzhuo Lub,*()   

  1. aSchool of Materials Science and Engineering, Harbin Institute of Technology, Harbin, China
    bSchool of Materials Science and Engineering, Dalian Jiaotong University, Dalian, China
  • Received:2020-08-05 Revised:2020-10-15 Accepted:2020-10-27 Published:2021-06-30 Online:2020-11-22
  • Contact: Yongjiang Huang,Yunzhuo Lu
  • About author:luyz@djtu.edu.cn (Y. Lu).
    * E-mail addresses: yjhuang@hit.edu.cn (Y. Huang),

Abstract:

Here, a single-track CoCrFeMnNi high entropy alloy (HEA) was successfully fabricated by laser melting deposition (LMD). Combining the experimental observations and numerical simulation, the microstructure and mechanical properties of the as-deposited parts were systematically studied from the perspective of thermo-mechanical history experienced during the LMD process. The strengthening mechanisms of the LMDed CoCrFeMnNi HEA parts were clarified. The frictional stress strengthening, grain boundary strengthening and dislocation strengthening contributed the whole yield strength of the parts. Dislocation strengthening dominated the strengthening mechanism. It was expected that the establishment of the relationship between thermo-mechanical history, microstructure and mechanical properties of the LMDed CoCrFeMnNi HEA could shed more insights into achieving HEA parts with the desired microstructure and high performance.

Key words: Laser melting deposition, High entropy alloy, Thermo-mechanical history, Microstructure, Mechanical property, Strengthening mechanisms