Understanding the Interdependence of Penetration Depth and Deformation on Nanoindentation of Nanoporous Silver

Abstract

A silver-based nanoporous material was produced by dealloying (selective chemical etching) of an Ag38.75Cu38.75Si22.5 crystalline alloy. Composed of connected ligaments, this material was imaged using a scanning electron microscope (SEM) and focused ion-beam (FIB) scanning electron microscope tomography. Its mechanical behavior was evaluated using nanoindentation and found to be heterogeneous, with density variation over a length scale of a few tens of nanometers, similar to the indent size. This technique proved relevant to the investigation of a material’s mechanical strength, as well as to how its behavior related to the material’s microstructure. The hardness is recorded as a function of the indent depth and a phenomenological description based on strain gradient and densification kinetic was proposed to describe the resultant depth dependence.

Advances in Focused Ion Beam Tomography for Three-Dimensional Characterization in Materials Science

“…The microstructure and the mechanical behavior of Al-SiC nanolaminates, obtained by magneton sputtering deposition, were the focus of the work by Mayer et al [169]. The response to nanoindentation for a silver-based nanoporous material, obtained by a selective chemical etching of an Ag 38.75 Cu 38.75 Si 22.5 crystalline alloy, was determined in the work of Champion [170]. The 3D FIB reconstruction was used to understand the mechanical behavior during this type of analysis.…”

Trends in Plasticity of Metals and Alloys

“…Finally, two papers are devoted to nonconventional materials which are attracting strong attention in view of elaborating lighter materials and simultaneously improving mechanical properties [9,10]. A crystalline silver alloy with a complex microstructure associated with nanometric-size porosity obtained by selective chemical etching is studied in [9].…”

“…Finally, two papers are devoted to nonconventional materials which are attracting strong attention in view of elaborating lighter materials and simultaneously improving mechanical properties [9,10]. A crystalline silver alloy with a complex microstructure associated with nanometric-size porosity obtained by selective chemical etching is studied in [9]. Using electron tomography and a nanoindentation technique, the paper aims at interpreting a highly heterogeneous mechanical behavior characterized by a complex relationship between the indenter penetration depth, the porosity, and the microstructure.…”