Elastic properties of a tungsten-silver composite by reconstruction and computation

TL;DR

This study reconstructs a 3D tungsten-silver composite microstructure from 2D images and computes its elastic properties across a temperature range, validating results with experimental data and theoretical bounds.

Contribution

It introduces a statistical reconstruction method for 3D microstructures and evaluates their elastic moduli using finite element analysis and theoretical bounds.

Findings

Computed Young's modulus agrees with experimental data.

Reconstructed models show deviations from self-consistent predictions.

Measured moduli are near upper bounds when phase properties are similar.

Abstract

We statistically reconstruct a three-dimensional model of a tungsten-silver composite from an experimental two-dimensional image. The effective Young's modulus ($E$) of the model is computed in the temperature range 25-1060^o C using a finite element method. The results are in good agreement with experimental data. As a test case, we have reconstructed the microstructure and computed the moduli of the overlapping sphere model. The reconstructed and overlapping sphere models are examples of bi-continuous (non-particulate) media. The computed moduli of the models are not generally in good agreement with the predictions of the self-consistent method. We have also evaluated three-point variational bounds on the Young's moduli of the models using the results of Beran, Molyneux, Milton and Phan-Thien. The measured data were close to the upper bound if the properties of the two phases were similar ($1/6 < E_1 /E_2 < 6$).