Promoting nanoscale deformation twinning through FCC phase decomposition in AlCoCrFeMo0.05Ni2 high entropy alloy

The high temperature plasticity of AlCoCrFeMo0.05Ni2 high entropy alloy (HEA) is significantly enhanced after annealing. However, the specific mechanisms are not fully understood. In this study, a polycrystalline HEA model with dimensions of 18 nm×18 nm×26 nm was used to analyze stress mapping under uniaxial tension through Large-scale Atomic/Molecular Massively Parallel Simulator (LAMMPS). Complemented by experimental results, one can see that the decomposition of the FCC phase promotes the formation of nanoscale deformation twins. The formation of deformation twinning is most likely one of the primary reasons for the substantial improvement in high temperature plasticity. The findings provide valuable insights for controlling the high temperature performance of the alloy.