1. Performances of mullite fiber reinforced glass sealing materials applied to high temperature solid oxide fuel cell.
- Author
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Ge, Ben, Liu, Xiaoxu, Guo, Mengyuan, Li, Jie, Shen, Rui, and Yang, Zhibin
- Subjects
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SOLID oxide fuel cells , *HEAT resistant materials , *GLASS fibers , *COMPOSITE materials , *MULLITE - Abstract
Glass sealing materials applied in Solid Oxide Fuel Cell (SOFC) are prone to excessive softening and outflow at high temperatures, while cracks tend to form upon cooling. To address these challenges, this study develops mullite fiber reinforced glass sealing materials based on K 2 O–Na 2 O–CaO–BaO–SiO 2 silicate glass, incorporating varying amounts of mullite fibers. The mechanical properties, phase structural transformations, and microstructural changes of these composite sealing materials are thoroughly investigated. The fibers form a network skeletal structure within the sealing material, enhancing the material's strength and high-temperature thermal stability. By incorporating 10% mullite fibers, the G10 sealing material, as compared to pure glass, exhibits a 44% increase in flexural strength and an 85% improvement in maximum strain value. Additionally, G10 boasts a thermal expansion coefficient of 10.25 × 10−6 K−1, demonstrating excellent chemical compatibility with interconnect and achieving tight adhesion at the interface. Most importantly, G10 possesses superior sealing capabilities, maintaining its gastightness even after undergoing 1000 h and 7 thermal cycles without any degradation. • The mullite fiber improves the strength and toughness of the sealing materials. • Mullite fiber form a support structure in the glass and prevent the glass flowing out. • The additional mullite fiber significantly hindered the chromium diffusion at the sealant/interconnect interface. • The leakage rate of the mullite fiber-glass composited sealing material is less than 0.002 sccm cm−1. • The sealant remain gas tightness after 1000 h at 750 °C and 7 thermal cycles. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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