Superplastic-like deformation in metallic amorphous/crystalline nanolayered micropillars

In this study, the ZrCu thin film metallic glasses (TFMGs) are incorporated with soft Cu thin film layers with optimum film layer thickness. Such multilayered amorphous/crystalline samples exhibit superplastic-like homogeneous deformation at room temperature. It is found that the deformability of the resultant micropillars depends on the thickness of Cu layers. Microstructural observations and theoretical analysis suggest that the superplastic-like deformation mode is attributed to homogeneous co-deformation of amorphous ZrCu and nanocrystalline Cu layers because the 100-nm-thick Cu layers can provide compatible flow stress and "plastic zone" size well matched with those of ZrCu amorphous layers.