Size effects on the mechanical behavior of nanoporous Au.
Recent nanomechanical tests on submicron metal columns and wires have revealed a dramatic increase in yield strength with decreasing sample size. Here, we demonstrate that nanoporous metal foams can be envisioned as a three-dimensional network of ultrahigh-strength nanowires, thus bringing together two seemingly conflicting properties: high strength and high porosity. Specifically, we characterized the size-dependent mechanical properties of nanoporous gold using a combination of nanoindentation, column microcompression, and molecular dynamics simulations. We find that nanoporous gold can be as strong as bulk Au, despite being a highly porous material, and that the ligaments in nanoporous gold approach the theoretical yield strength of Au.
Biener
Juergen
J
Nanoscale Synthesis and Characterization Laboratory, Lawrence Livermore National Laboratory, P.O. Box 808, L-367, Livermore, California 94550, USA. biener2@llnl.gov
Hodge
Andrea M
AM
Hayes
Joel R
JR
Volkert
Cynthia A
CA
Zepeda-Ruiz
Luis A
LA
Hamza
Alex V
AV
Abraham
Farid F
FF
D019245:Compressive Strength; D004548:Elasticity; D006046:Gold / Q000737:chemistry*; D006244:Hardness; D008422:Materials Testing; D019563:Mechanics; D008968:Molecular Conformation; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D010316:Particle Size; D016062:Porosity; D013314:Stress, Mechanical; D013499:Surface Properties; D013718:Tensile Strength
D006046:Gold