Long-term stability of SOFC glass sealant under oxidising and reducing atmospheres

The behaviour of the 59.6SiO(2)-11.0Al(2)O(3)-6.6ZrO(2)-3.4CaO-15.4Na(2)O-4Y(2)O(3) (wt. %) non-crystallising glass sealant was studied while in contact with NiO-YSZ (yttria-stabilized zirconia) ceramics and an Fe-Ni alloy after exposure to reducing and oxidising atmospheres at 850 degrees C and while on a Pt substrate. The sealant was completely amorphous after exposure on a Pt substrate for 1000 h in an air atmosphere. After exposure on a NiO-YSZ substrate in both oxidising and reducing atmospheres, no interaction on the NiO(Ni)-YSZ|sealant interface was observed. For the Fe-Ni alloy substrate, the formation of an Fe2SiO4 layer was observed after exposure in an oxidising atmosphere. In the reducing atmosphere, the Fe-Ni alloy substrate intensified sealant crystallisation, leading to the formation of numerous crystalline phases, but no interaction on the Fe-Ni alloy| sealant interface was observed.

Automated summary

This study investigated the behavior of a non-crystallising glass sealant in contact with NiO-YSZ ceramics and an Fe-Ni alloy under different atmospheres and substrate materials. The results showed variations in the performance and behavior of the sealant under different conditions.