International Journal of Hydrogen Energy, vol.45, no.60, pp.35118-35129, 2020 (SCI-Expanded)
© 2020 Hydrogen Energy Publications LLCIn this study, the joint strengths of glass-ceramic sealant placed between two metallic interconnectors (Crofer® 22 APU) are experimentally investigated depending on the surface conditions of the metallic interconnector and electrolyte/electrode materials (YSZ and NiO). The surfaces of the interconnectors are sanded with sandpaper having five different grits (60, 120, 240, 320 and 2000 grits). Thus, roughened surfaces are obtained and the adhesion is examined for each case. Profilometer is used to inspect the surface roughness of the samples. The fracture strengths of 24 samples prepared for each case are determined via tensile tests. Similarly, different electrolyte/electrode materials with modified surfaces are sandwiched between two glass ceramic layers and their mechanical performances are also measured. The results reveal that the joining strength tends to increase with the amount of surface roughness. It is also found that NiO adheres better to glass-ceramic material than YSZ. The microstructures of the adhesion interface of some cases are also investigated by a scanning electron microscopy. The images showed that good adhesion is achieved without any delamination or cracks at the interfaces. Chemical formation between the glass-ceramic sealants, interconnects and SOFC components is further investigated by XRD analyses.