Evaluation of Creep Properties in Anode Materials for Solid Oxide Fuel Cells by Using Small Punch Testing Method

Abstract

To assess the mechanical reliability and durability of solid oxide fuel cells (SOFCs), a suitable creep test method needs to be developed. The objective of this study is to examine the potential of small punch (SP) method as a simple creep testing method for SOFCs. In this study, the creep properties of Ni-YSZ composites were evaluated at temperatures of 800-900˚C, and at stresses of 47.3 to 89.8 MPa under 1% hydrogen environment. The obtained creep curves by the SP method showed three stages: initial transition creep, secondary creep, and tertiary stages. The central displacement versus time data obtained by the SP method was found to be characterized by a power law relationship. Even though quantitative comparisons need to be made with conventional methods, the above result suggests the usefulness of the SP methods for characterizing the creep properties in constituent materials of SOFCs.

Relationship between microstructure and deformation of porous Ni-based cermets under redox cycling

“…As for Ni-YSZ, it has been reported that it gradually decreases as the temperature rises. Watanabe et al [5] and Huang et al [6] also systematically examined and discussed the fracture behavior and creep deformation of Ni-based cermet porous bodies during Redox cycles. Wang et al [7] built a 3D model based on the finite element method (FEM) to investigate the effect of inhomogeneous oxidation of anode on mechanical degradation of SOFC.…”