Spherical indentation of bilayer ceramic structures: dense layer on porous substrate
File(s)
Published version
Author(s)
Chen, Z
Wang, X
Brandon, N
Atkinson, A
Type
Journal Article
Abstract
Spherical indentation of thin 8YSZ ceramic layers on porous substrates (NiO/Ni-8YSZ) was studied. Indentation-induced elastic and plastic deformation and damage of the bilayer was experimentally analysed. FE simulations of the indentation process were carried out using the Gurson model to account for densification of the porous substrates. The simulated load-depth responses were in excellent agreement with the measured ones. The resulting stress distributions showed that the damage to the YSZ initiates in a tensile region near the interface due to bending during loading at a failure stress of ∼2 GPa, which is consistent with pores of ∼1 μm size seen in the YSZ. Delamination occurs on unloading due to the elastic recovery of YSZ being greater than that of the substrates at a de-bonding stress of 120 MPa. Residual compressive stress in the YSZ inhibits crack opening displacements normal to the layer plane which is beneficial for application of these structures in SOFCs.
Date Issued
2017-06-04
Date Acceptance
2017-05-27
Citation
Journal of the European Ceramic Society, 2017, 37 (15), pp.4763-4772
ISSN
1873-619X
Publisher
Elsevier
Start Page
4763
End Page
4772
Journal / Book Title
Journal of the European Ceramic Society
Volume
37
Issue
15
Copyright Statement
© 2017 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY license(http://creativecommons.org/licenses/by/4.0/).
License URL
Sponsor
Engineering & Physical Science Research Council (EPSRC)
Engineering & Physical Science Research Council (EPSRC)
Grant Number
EP/J016454/1
EP/M014045/1
Subjects
0912 Materials Engineering
Materials
Publication Status
Published