Project description

The overarching goal of this research project is to develop a mechanistically informed model incorporating microstructural length-scale effects into scaling laws to describe the mechanical behaviour of nanoporous gold composites at different hierarchical scales.

The approach taken incorporates micromechanical experiments, microstructural characterization and multiscale-modelling approaches with which the influences of salient structural characteristics will be identified and carried over to coarsened models. To this end, neural network modelling will be used to identify a critical subset of structural parameters needed to describe experimentally observed mechanical response. Unlike traditional materials, it is unclear a priori what the influence of size and hierarchical level is on the mechanisms of deformation; size-dependant and hierarchy-dependant deformation mechanisms must be explicitly identified through targeted micromechanical experiments to investigate structural influences of NPG and the NPG/polymer interface effects.

The model development is based on outcomes from both experiments and modeling from the first funding phase. Describing the mechanical behavior of NPG is makes use of beam models for achieving relevant deformation modes with increased computational efficiency, as a function of structural parameters such as solid fraction, ligament size distribution, and structural disorder. Furthermore the mechanical properties of bulk and interphases in the polymer of infiltrated NPG are to be identified in dependence of the scaling of the pore space.

In the end, a key challenge will be to find appropriate homogenization schemes in order to predict the mechanical behavior over several hierarchical levels in the material system for such complex, multiscale material systems.

Project leaders
Prof. Dr. Erica T. Lilleodden,
HZG
Contact
Prof. Dr. Norbert Huber,
HZG
Contact
 Keywords

micromechanics

interfaces & interphases

scaling laws                   composites     

nanoporous materials

FEM           RVEs

scale bridging

Publications

1. K. Hu, M. Ziehmer, K. Wang, E.T. Lilleodden: Nanoporous gold: 3D structural analyses of representative volumes and their implications on scaling relations of mechanical behaviour. Philosophical Magazine 96, 3322-3335, 2016

2. J. Jiao & N. Huber: Deformation mechanisms in nanoporous metals: Effect of ligament shape and disorder Computational Materials Science 127, 194-203, 2017

... and more on the list of publications.

 


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