Strengthening of Al0.3CoCrFeMnNi-based ODS high entropy alloys with incremental changes in the concentration of Y2O3

The high-entropy alloy (HEA) composite Al0.3CoCrFeMnNi based on the face-centered-cubic (FCC) system and reinforced with 0-3 vol% Y2O3 was processed by mechanical alloying followed by spark plasma sintering (SPS). The compressive yield strength of the Alo(3)CoCrFeMnNi high-entropy alloy (HEA) increased phenomenally, from 0.98 GPa (0 vol% Y2O3) to 1.76 GPa (3 vol% Y2O3). A quantitative analysis by atom probe tomography (APT) suggested the in-situ formation of complex oxide resulting from the reaction of Y2O3 with the HEA matrix during processing, enhancing the strength. Using the dispersion-barrier hardening model, the strengthening by dispersoids in Ala(3)CoCrFeMnNi with Y2O3 was calculated, and closely matched the experimental results. (C) 2018 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.