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

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. (C) 2021 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.