Atomistic Simulations of Ductile Failure in a b.c.c. High-Entropy Alloy

Ductile failure is studied in a bcc HfNbTaZr High-Entropy Alloy (HEA) with pre-existing void. Using molecular dynamics simulations of uniaxial tensile tests, we explore the effect void radius on elastic modulus and yield stress. The scales porosity as closed-cell foams. critical stress for dislocation nucleation function very well described by model designed after pure metals, taking into account larger core HEA. Twinning takes place complementary deformation mechanism, some detwinning occurs at large strain. No solid–solid phase transitions are identified. concurrent effects element size mismatch plasticity lead to significant lattice disorder. By comparing our HEA results tantalum simulations, show that resulting densities much lower than Ta, expected from energy barriers due chemical complexity.