Mechanical properties of nanoporous gold in tension

Abstract

We report results of the tensile properties of nanoporous gold (NPG) as a function of the density and average ligament diameter. As-dealloyed tensile samples were thermally treated to coarsen the length scale of the NPG structure while increasing the sample density resulting from thickness reductions. The behaviors of samples with mean ligament diameters ranging from 30-750 nm and corresponding densities ranging from 0.30-0.57 that of bulk gold were examined. Digital image analysis was used to obtain ligament size histograms that were fit to the Weibull distribution. The Young's modulus was found to obey a power law, but with an exponent larger than that predicted by Gibson-Ashby scaling. The fracture behavior showed a brittle-ductile transition as a function of increasing ligament size. For samples characterized by a mean ligament diameter less than ~ 220 nm, the tensile behavior was linear elastic to sample fracture while samples with larger scale ligaments showed macroscopic yielding prior to fracture. These results are interpreted within the framework of extreme value statistics.

Light Gold: A Colloidal Approach Using Latex Templates

“…Ashby plot showing the Young's modulus and density of metals, metal foams, polymers, and metal–polymer hybrid composite nanopillars as reported by Dusoe et al The light gold composites as reported herein fill the white space between the metallic and polymeric materials as indicated in gray.…”

“…Fabrication of Organic-Inorganic Aerogel: After diffusion of salt for 24 h, the gel was placed in an aluminum cage directly in the salt bath for 1 h to ensure all fibril entanglement points were converted into crosslinks. The cage with the hydrogel was then transferred into 50% EtOH and 50% pH 2 milli-Q water bath (100 mL) for 24 h. This was followed by [53] showing the Young's modulus and density of metals, [46] metal foams, [49,54,55] polymers, [47,48] and metal-polymer hybrid composite nanopillars as reported by Dusoe et al [52] The light gold composites as reported herein fill the white space between the metallic and polymeric materials as indicated in gray. two subsequent transfers into 99% EtOH (100 mL) for 24 h to complete the solvent exchange.…”

“…A scaling exponent of ≈3.6 is typical for porous dried gels with large mass fractal dimension. [44][45][46] Applying of vacuum during annealing compared to atmospheric conditions had again the most significant effect with an order of magnitude higher Young's modulus for the sample annealed under vacuum with ρ app = 0.80 g cm −3 (E = 3500 kPa) compared to the sample annealed under atmospheric pressure with ρ app = 0.72 g cm −3 (E = 604 kPa), while prepared with identical starting solutions. All values are reported in Table 1.…”

A fully molecular dynamics-based method for modeling nanoporous gold

“…To compare NPG models, different structural properties can be used, such as the ligaments diameter distribution (D m ), the scaled genus density (g v ) which quantifies the connectivity, and the interfacial shape distribution (ISD) which is the dis-tribution of the local curvature of the ligaments and characterizes the morphology. The structural properties of NPG are highly correlated to mechanical or catalytic properties [1,15,24]. Models can also be compared on the basis of mechanical considerations.…”

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

“…Metallic nanoporous (NP) materials present interesting perspectives owing to their nanometric-size microstructure and large specific surface (extremely high open-porosity level). From the first feature, mechanical strength, unique plasticity, and multiphysical properties are expected [1][2][3][4][5]. The second is related to surface interactions and chemical reactivity, with perspectives in domains such as electrochemical energy storage and conversion, catalysts [6,7], biomedical implants [8], and filtering and purification [9].…”