Unveiling orientation dependence of anisotropic plasticity in polycrystalline copper by nanoindentation

The mechanical properties of crystalline materials are influenced by their deformation behavior, which is associated with their microstructural characteristics. Specifically, crystallographic orientation greatly affects the microscale plastic deformation of individual grains. In this study, experiments and finite element simulations of Berkovich nanoindentations are conducted to investigate the impact of crystallographic orientation in polycrystalline copper. A crystal plasticity constitutive model is developed for copper materials, which accurately captures their indentation mechanical response. The results showed that the indentation behavior of polycrystalline copper exhibits a high degree of anisotropy due to significant variation in slip systems for different crystallographic orientations. This results in different mechanical responses of individual grains and distinct material pileup morphologies on the indented surface. Additionally, the study revealed that crystallographic orientation plays a critical role in determining the indentation size effect. These findings have important implications for the design of materials where plasticity is a crucial factor.

Automated summary

In this study, the influence of crystallographic orientation on the nanoindentation behavior of polycrystalline copper was investigated through experiments and finite element simulations. The results showed a high degree of anisotropy in the indentation behavior due to different slip systems for different crystallographic orientations, leading to different mechanical responses and distinct material pileup morphologies. Furthermore, it was found that crystallographic orientation plays a critical role in determining the indentation size effect.