Abstract
This paper presents a new modelling technique using three-dimensional multi-phase finite element models in which meshes representing the microstructure of thermally oxidised nuclear graphite were generated from X-ray micro-tomography images. The density of the material was related to the image greyscale using Beer-Lambert's law, and multiple phases could thus be defined. The local elastic and non-linear properties of each phase were defined as a function of density and changes in Young's modulus, tensile and compressive strength with thermal oxidation were calculated. Numerical predictions compared well with experimental data and with other numerical results obtained using two-phase models. These models were found to be more representative of the actual microstructure of the scanned material than two-phase models and, possibly because of pore closure occurring during compression, compressive tests were also predicted to be less sensitive to the microstructure geometry than tensile tests.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 46-58 |
| Number of pages | 13 |
| Journal | Journal of Nuclear Materials |
| Volume | 380 |
| Issue number | 1-3 |
| DOIs | |
| State | Published - Oct 15 2008 |
Bibliographical note
Funding Information:British Energy Generation Ltd. is gratefully acknowledged for their financial support (Contract No. GRA/GNSR/6023). The views expressed in this paper are those of the authors and do not necessarily represent those of the sponsor.