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Pure metallic nanofoams in the form of interconnected networks have shown strong potentials over the past few years in areas such as catalysts, batteries, and plasmonics. However, they are often fragile and difficult to integrate into engineering applications. To better understand their deformation mechanisms, a multiscale approach is required to simulate the mechanical behavior of the nanofoams, although these materials will operate at the macroscale, they will still be maintaining an atomistic ordering. Hence, in this work, we combine molecular dynamics (MD) and finite element analysis (FEA) to study the mechanical behavior of copper (Cu) nanofoams. Molecular dynamics simulations were performed to investigate the yield surface of a representative cell structure. The nanofoam structure has been generated by spinodal decomposition of binary alloy using an atomistic approach. Then, the information obtained from the molecular dynamics simulations in the form of yield function is transferred to the finite element model to study the macroscopic behavior of the Cu nanofoams. The simulated mechanical conduct of Cu nanofoams is in good agreement of the real experiment results.
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A Multiscale Simulation Approach for the Mechanical Response of Copper/Nickel Nanofoams With Experimental Validation
Abstract Metallic nanofoams, cellular structures consisting of interlinked thin nanowires and empty pores, create low density, high surface area materials. These structures can suffer from macroscopically brittle behavior. In this work, we present a multiscale approach to study and explain the mechanical behavior of metallic nanofoams obtained by an electrospinning method. In this multiscale approach, atomistic simulations were first used to obtain the yield surfaces of different metallic nanofoam cell structures. Then, a continuum plasticity model using finite elements was used to predict the alloy nanofoam's overall strength in compression. The manufactured metallic nanofoams were produced by electrospinning a polymeric non-woven fabric containing metal precursors for alloys of copper–nickel and then thermally processing the fabric to create alloy metallic nanofoams. The nanofoams were tested with nanoindentation. The experimental results suggest that the addition of nickel increases the hardening of the nanofoams. The multiscale simulation modeling results agreed qualitatively with the experiments by suggesting that the addition of the alloying can be beneficial to the hardening behavior of the metallic nanofoams and helps to isolate the effects of alloying from morphological changes in the foam. This behavior was related to the addition of solute atoms that prevent the free dislocation movement and increase the strength of the structure.
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- PAR ID:
- 10287203
- Date Published:
- Journal Name:
- Journal of Engineering Materials and Technology
- Volume:
- 144
- Issue:
- 1
- ISSN:
- 0094-4289
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1115/1.4051806
