@misc{richert_finite_element_2017, 
author={Richert, C.,Hu, K.,Huber, N.},
title={Finite Element Modelling of Nanoporous Gold Based on Skeletonization of 3D FIB-SEM Tomography Data},
year={2017},
howpublished = {conference poster: Boston, MA. (USA); 26.11.2017 - 01.12.2017},
abstract = {Nanoporous Gold (NPG) made by dealloying takes the form of macroscopic millimetre- to centimetresized,porous bodies with a solid fraction around 30%. The material exhibits a uniform, bicontinuous network of,nanoscale pores and solid ligaments. The relationship between the solid fraction and the macroscopic mechanical,behavior is commonly described by the Gibson-Ashby scaling laws for open cell foams. However, one main,observation of various experimental studies is a much lower leading constant, in several cases combined with a higher,exponent within the Gibson-Ashby scaling law for the Young’s modulus.,For deeper understanding of the mechanical behavior and the occurring deformation mechanisms, various modelling,approaches are suggested in literature, which simplify the complex NPG network to unit cell structures such as cubic,,diamond or three point bending beam. This significant simplification and yet lack of satisfactory understanding of the,underlying structure-property relationship brings the risk of losing detailed insight into the real NPG structure, and,thus, possibly important aspects of its mechanical behavior.,Liu et al. (2016) attribute the discrepancy between experiments and the Gibson-Ashby scaling law to a lowered,network connectivity of the NPG structure seen in SEM-images: Some ligaments are dangling ligaments and thus,cannot carry external load. They introduced the “effective relative density” which is much lower than the real relative,density of the examined NPG samples. In the study of Hu et al. (2016) tomographic reconstructions of NPG samples,using a dual-beam FIB and SEM were carried out for the first time. For different samples with varying ligament size, it,was reported that the effective solid fraction is approximately half of the measured solid fraction. The authors likewise,show, that the effective load-bearing ring structure governs the mechanical behavior, rather than the solid volume,fraction.,This paper presents a computational cheap FEM beam model, which is based on skeletonization of such 3D FIB-SEM,tomography data of NPG to bridge computer simulations and experiments. The FEM skeleton beam model is,validated using a FEM solid model generated from the very same 3D tomographic data. Various FEM skeleton beam,models are generated for varying sample sizes out of the 3D FIB-SEM tomography. The resulting macroscopic,properties are analysed in dependence of structural characteristic parameters, such as effective solid fraction and,connectivity, and are compared to results obtained from idealized diamond unit cell structures. The models allow,clarifying the role of dangling ligaments and load bearing rings in terms of the effective relative density. Furthermore,,concerning the diamond structure, the FEM skeleton beam model provides an answer to the question of the,percentage of nodes that are connected with three respectively four ligaments, needed for predicting a macroscopic,response close to the real NPG.},
note = {Online available at: \url{} (DOI). Richert, C.; Hu, K.; Huber, N.: Finite Element Modelling of Nanoporous Gold Based on Skeletonization of 3D FIB-SEM Tomography Data. In: MRS Fall Meeting 2017. Boston, MA. (USA). 2017.}}