The effect of free volume on the deformation behaviour of a Zr-based metallic glass under nanoindentation

In this paper, the deformation behaviour of Zr65Cu17.5Ni10Al7.5 metallic glasses with different amounts of free volume was investigated with nano- and micro-indentation. It was found that the plastic flow of the metallic glasses is closely related to the amount of free volume. The metallic glasses with more free volume exhibit more conspicuous serrations with a larger pop-in size during nanoindentation and more pronounced shear bands during micro- indentation. The effect of free volume on the deformation behaviour of the Zr-based metallic glasses is discussed in terms of free volume theory.