Influence of NiO Reduction on Residual Strain in NiO/Ni-YSZ

Influence of NiO Reduction on Residual Strain in NiO/Ni-YSZ

The residual strains in the composites of nickel oxide (NiO) and yttria-stabilized zirconia (YSZ) and in the cermets of reduced nickel (Ni) and YSZ, which were used as anodes for solid oxide fuel cells (SOFCs), were measured using X-ray diffraction. The influence of Ni reduction on the residual stra...

Full description

Saved in:
Bibliographic Details
Published in:MATERIALS TRANSACTIONS Vol. 59; no. 1; pp. 27 - 32
Main Authors: Iguchi, Fumitada, Akrasevee, Sarana, Miyoshi, Yutaro
Format: Journal Article
Language:English
Published: Sendai The Japan Institute of Metals and Materials 01-01-2018
Japan Science and Technology Agency
Subjects:
Anodes
Cermets
Compressive properties
Deformation mechanisms
Dependence
Nickel
nickel oxide reduction
Nickel oxides
Plastic deformation
Reduction
residual strain
residual stress
Solid oxide fuel cells
Thermal strain
volume fraction dependence
X-ray diffraction
XRD
Yttria-stabilized zirconia
Yttrium oxide
Zirconium dioxide
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The residual strains in the composites of nickel oxide (NiO) and yttria-stabilized zirconia (YSZ) and in the cermets of reduced nickel (Ni) and YSZ, which were used as anodes for solid oxide fuel cells (SOFCs), were measured using X-ray diffraction. The influence of Ni reduction on the residual strain was evaluated. Tensile and compressive residual strains caused by thermal strain were observed in NiO and YSZ phases, respectively. They clearly depended on the volume fraction of NiO and YSZ, and changed proportionally. The YSZ phase in the Ni-YSZ cermets also showed a similar dependence on the volume fraction of NiO. The compressive strain increased as the NiO increased; however, a local maximum was observed for NiO 50 vol%, beyond which it decreased with increasing amount of NiO. Compressive strain in the YSZ phase in the Ni-YSZ with NiO of 60 vol%, which is a common volume fraction of SOFC anodes, was only 30% of that in the NiO-YSZ. Plastic deformation of the Ni phase near the interfaces, and relaxation of the compressive strain in the YSZ phase were responsible for this phenomenon. This revealed the difference in the residual strain in the YSZ phase after reduction.
ISSN:1345-9678
1347-5320
DOI:10.2320/matertrans.MB201703