Tensile deformation and fracture mechanisms of Cu/Nb nanolaminates studied by in situ TEM mechanical tests

TL;DR

This study investigates the deformation and fracture mechanisms of Cu/Nb nanolaminates using in-situ TEM mechanical tests, revealing orientation-dependent mechanical behavior and failure modes.

Contribution

It provides new insights into the anisotropic deformation and fracture mechanisms of Cu/Nb nanolaminates through in-situ TEM analysis.

Findings

Deformation parallel to layers shows high strain hardening and ductility.

Perpendicular deformation results in more brittle behavior.

Microstructural analysis explains orientation-dependent failure modes.

Abstract

The mechanisms of deformation and failure of Cu/Nb nanolaminates manufactured by accumulated roll bonding were analysed using in-situ TEM mechanical tests. Dog-bone small-scale tensile specimens were prepared using a FIB-based technique with the layers parallel and perpendicular to the loading axis. Load, deformation and TEM micrographs were recorded during the in-situ TEM mechanical tests. The specimens deformed parallel to the layers presented very high strain hardening and ductility while those deformed in the perpendicular orientation were more brittle. These results were rationalized in terms of the deformation and fracture mechanisms observed during the tests.