We perform molecular dynamics simulations of nanoindentation in bilayer systems composed of a ${\text{Cu}}_{64.5}$${\text{Zr}}_{35.5}$ metallic glass and a pure Cu crystalline sample. Both the cases where the glass and where the crystal is top are studied. We find a strong asymmetry in the response of the glass-top and the crystal-top system. The crystal-top system is the weakest one. Here, dislocations nucleate at the interface and also induce considerable strain in the glass layer beneath; hence the interface acts to reduce the plastic activity in the top crystal layer. In contrast, the glass-top system is the hardest system of the four systems studied. Shear bands form considerably earlier in the glass-top system than in a pure glass. The interface hinders shear band propagation; it thus causes a deflection of the load exerted by the indenter and hardens the material. Dislocations in the bottom crystal can be generated only when the indenter has penetrated the interface.

我们在由下列组成的双层系统中进行纳米压痕的分子动力学模拟 ${\text{铜}}_{64.5}$${\text{锆}}_{35.5}$金属玻璃和纯铜晶体样品。研究了玻璃和晶体位于顶部的情况。我们在玻璃顶和晶体顶系统的响应中发现很强的不对称性。水晶顶系统是最薄弱的系统。在此，位错在界面处成核，并在下方的玻璃层中引起可观的应变。因此，界面起着降低顶层晶体层塑性活动的作用。相反，玻璃顶系统是所研究的四个系统中最难的系统。玻璃顶系统中的剪切带比纯玻璃中的剪切带形成的时间要早​​得多。界面阻碍了剪切带的传播；因此，它会导致压头施加的载荷发生偏斜，并使材料变硬。仅当压头已穿透界面时，才能在底部晶体中产生位错。