Mechanical Strength Evaluation of YSZ, GDC and LSCF under SOFC Operating Conditions

摘要

Our group has attempted to construct multiscale model which can simulate elastic and inelastic deformation and fracture probability with consideration of electrochemical, thermal and mechanical properties of constituent materials. The model requires the details of material properties to simulate cells/stacks under operating conditions. In this study, we focus on mechanical properties of SOFC materials including 8YSZ electrolyte, 10GDC barrier layer and LSCF6428 cathode which are well-known as brittle materials, and evaluated their elasticity, fracture properties and strain using Small Punch (SP) test. Mechanical characteristics of 8YSZ showed drastic change in the intermediate temperature range. LSCF6428 exhibited the trends of ferroelasticity and the fracture strength inversely correlated with the fracture strain for temperature variation. Fracture strain of 10GDC was the smallest among three materials in the whole testing temperature range.