Effects of Silver Addition on Mechanical Properties of Plasma Sprayed SOFC Interconnect Layer

In this study, interconnect layer of solid oxide fuel cell (SOFC) was built up from spray-dried La_0.6Sr_0.4Co_0.2Fe_0.8O_3-δ (LSCF) and blended LSCF-Ag through atmospheric plasma spraying (APS). Microstructure and phase of each coating was analyzed through scanning electron microscopy (SEM) and X-ray diffraction (XRD) respectively. Furthermore, bond strength, micro-hardness, thermal cycle test and oxidation test were performed and compared. The coatings prepared from spray-dried LSCF have higher porosity and cracks at inter-particle boundaries. However, the coatings with silver addition presented reduced cracks and porosity due to relatively high ductility of silver, resulting in higher mechanical properties.