Serration behavior and negative strain rate sensitivity of Al0.1CoCrFeNi high entropy alloy

Temperature dependent deformation mechanism of Al0.1CoCrFeNi high entropy alloy (HEA) was studied using monotonic and strain rate jump tests at various test temperatures in a coarse-grained single phase FCC HEA. The tensile properties of Al0.1CoCrFeNi HEA exhibited a modest temperature dependence in the tested range of 300-673 K. At an initial strain rate of 10(-5) s(-1), the serration type was a function of the test temperature. Furthermore, the strain rate sensitivity of the flow stress changed from positive to zero to negative once the unstable plastic deformation region due to dynamic strain aging was attained. (C) 2016 Elsevier Ltd. All rights reserved.