Role of interfacial transition zones in the fracture of Cu/V nanolamellar multilayers

Abstract

Plastic deformation and fracture behavior of Cu/V nanoscale metallic multilayers (NMMs) were systematically investigated through in situ transmission electron microscopy testing. Two different types of interfaces: sharp interfaces and interfacial transition zones (ITZs), formed in the as-fabricated Cu/V NMMs. Upon deformation, sharp interfaces and ITZs exert distinct influences on the fracture behavior of Cu/V NMMs. Sharp interfaces can impede the crack propagation by deflecting the crack propagation and blunting the crack tip, while the ITZs can induce microcracks and facilitate the fracture process. These findings shed light on the important roles of interface structures in the deformation of a broad class of NMMs. IMPACT STATEMENT In situ nanomechanical testing reveals critical roles of interface structures on the fracture of Cu/V NMMs, where sharp interfaces imped and deflect cracks but interfacial transition zones facilitate the fracture greatly.

Crack mediated dislocation activities in Al/Ti nanolayered composites: an atomistic study

“…Crack propagation is also influenced by the nature of interface [23]. A coherent interface allows dislocations to pass through due to nearly continuous slip system across the interface [24].…”

“…A sharp interface deflects the crack due to different slip systems across the interface, but an interfacial transition zone accelerates the fracture process by creating new micro-cracks [23]. In absence of a pre-existing crack, the crack in the multilayer can be initiated by subjecting it to bending, and the strain required to initiate such a crack also increases with an increase in layer thickness [26].…”