Dislocation dynamics in Al0.1CoCrFeNi high-entropy alloy under tensile loading

Abstract

The deformation mechanisms in a single phase face-entered cubic high-entropy alloy, Al0.1CoCrFeNi, under tensile loading are investigated using classical molecular simulations. Our atomistic model employed for quasi-statically straining the alloy is validated against the predictions of lattice structure, pair-correlations and material density. The Young's modulus determined from the linear stress-strain profile in the elastic regime concurs with previous experimental reports. During plastic deformation, we find that dislocation nucleation and mobility plays a pivotal role in initially triggering twin boundaries followed by the generation of intrinsic and extrinsic stacking faults in the alloy. At room temperature, we find dislocation annihilation contributes to the shear resistance of the alloy effecting a serration laden plastic flow of stress as uniaxial strain is increased.