Abstract

The CoCrFeNiMn high entropy alloy and its strengthened version by in-situ formed dispersion of yttria nano-oxides prepared via mechanical alloying were investigated. The grain refinement of the one phase FCC alloy by presence of oxides was determined by microstructural analyses to be 50%. The positive effect of oxide dispersion on the strength properties was found to be between 30% and 70% for room and elevated temperatures, respectively. The resulting creep strain rates for the strengthened alloy were significantly lower, i.e., three orders for 30 MPa stress level, comparing the initial one, therefore, the pining mechanism was among others very effective.