Confined Layer Slip Process in Nanolaminated Ag and Two Ag/Cu Nanolaminates

Abstract

The exceptional strength of nanolaminates is attributed to the influence of their fine stratification on the movement of dislocations. Through atomistic simulations, the impact of interfacial structure on the dynamics of an edge dislocation, which is compelled to move within a nanoscale layer of a nanolaminate, is examined for three different nanolaminates. In this study, we model confined layer slip in three structures: nanolaminated Ag and two types of Ag/Cu nanolaminates. We find that the glide motion is jerky in the presence of incoherent interfaces characterized by distinct arrays of misfit dislocations. In addition, the glide planes exhibit varying levels of resistance to dislocation motion, where planes with intersection lines that coincide with misfit dislocation lines experience greater resistance than planes without such intersection lines.

Mechanical Properties of Thermally Annealed Cu/Ni and Cu/Al Multilayer Thin Films: Solid Solution vs. Intermetallic Strengthening

“…For multilayers with an individual layer thickness of 50 nm and greater, strengthening occurs by dislocation pile-up at the layer interfaces which can be explained by the Hall-Petch relation [10][11][12][13]. When the layer thickness is between 10 and 50 nm, due to strong repulsion among like-sign coplanar dislocations, the multilayer strengthening can be explained by confined layer slip (CLS) [14][15][16][17], involving the movement of a single dislocation loop parallel to the interface within individual layers. The multilayer strength approaches the theoretical value when the layer thickness is around 5 nm.…”