Study on the internal structural changes of FeNiCoCrCu high-entropy alloy under different initial strains using molecular dynamics simulations

High-entropy alloys (HEAs), as a novel high-performance metal material, have garnered significant attention due to their substantial application potential. However, the advancement HEAs has been hindered by the substantial experimental costs and the intricate challenges posed by real-world environments. Fortunately, molecular dynamics (MD) simulations offer insights into the deformation behavior of metals under complex conditions, thus advancing the development of HEAs. This study utilizes MD simulations to investigate the Nanoindentation simulation of FeNiCrCoCu high-entropy alloy under different initial strains, based on existing experimental results. The internal structural transformations and the evolution of local dislocations and stacking faults were examined. The results indicate that the maximum load of the model reaches its peak at a strain of epsilon=0.04, =0.04, accompanied by the ejection of prismatic dislocation loops. In the epsilon=0 model, prismatic dislocation loops were generated but not ejected from the dislocation network formed in the indentation area. Increased deformation led to a significant proliferation of dislocations within the model and the generation of numerous amorphous atoms during stretching, resulting in a dramatic increase in dislocation density. The nucleation of dislocations shifted from beneath the indentation area to the amorphous atoms formed during stretching, leading to a decrease in the model's maximum load. This study enhances the understanding of the internal deformation mechanisms of HEAs in practical applications, and bridge the gap between laboratory research and practical applications.