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| 中文摘要： | |
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本研究主旨在探討經過不同時效處理之GC-9封裝玻璃陶瓷燒結試片，在800 oC下的潛變性質與破壞模式，並探討金屬連接板不銹鋼(Crofer 22 H)與封裝玻璃陶瓷接合件於800 oC下之潛變性質與不同負載模式下之破壞形態。 實驗結果顯示，經過1000小時時效處理後之GC-9玻璃陶瓷燒結試片，於相同的應力負載下，其變形量比未時效及100小時時效之試片來得低且具有較長的潛變壽命，此乃於結晶量較多及粗大化所致。藉由最小應變率來看，未時效試片之最小應變率明顯高於其時效處理後的試片，由此可證，時效時間越長，抵抗潛變變形的能力越高。在潛變壽命方面，欲達到1000小時以上之壽命，未時效、100小時時效及1000小時時效所施加的應力負載分別需小於6 MPa、9 MPa及15 MPa，再次證明經由時效過後的試片，所能承受之負載較大，抵抗潛變變形的能力越高。 關於GC-9玻璃陶瓷與Crofer 22 H金屬連接板接合件的潛變性質，接合件試片於800 oC下的剪力與拉力潛變壽命會隨著負載減少而增加。在剪力試片方面，具1000小時壽命的潛變強度約為剪力接合件強度的四分之一，而張力試片具1000小時壽命的潛變強度則約為張力接合件強度的百分之九。另外，對於剪力及張力潛變試片，不論其潛變壽命長短，其裂紋皆始於尖晶石與鉻酸鋇層之界面，隨後沿著鉻酸鋇層生長，而後在鉻酸鋇層與玻璃陶瓷基材之間交替遊走，最後在玻璃陶瓷基材內發生破壞。
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| Abstract： | |
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Creep properties at 800 oC are investigated for a newly developed solid oxide fuel cell glass-ceramic sealant (GC-9) in variously aged conditions using a ring-on-ring test technique. Creep properties of sandwich joint specimens made of GC-9 and a interconnect steel (Crofer 22 H) are also investigated at 800 oC under several constant shear and tensile loadings. When subjected to an applied constant load at 800 oC, the 1000 h-aged GC-9 can last longer than the non-aged and 100 h-aged ones before rupture. The 1000 h-aged GC-9 also exhibits a much smaller minimum creep strain rate than do the non-aged and 100 h-aged ones. Therefore, a longer aging time of 1000 h leads to a greater extent of crystallization and creep resistance at 800 oC for the given GC-9 glass-ceramic sealant. The creep strength at 1000 h is about 6 MPa, 9 MPa, and 15 MPa, for the non-aged, 100 h-aged, and 1000 h-aged GC-9, respectively. The creep rupture time of Crofer 22 H/GC-9/Crofer 22 H joint specimens is increased with a decrease in the applied constant load at 800 oC for both shear and tensile loading modes. The creep strength at 1000 h under shear loading is about one quarter of the shear strength at 800 oC. The tensile creep strength at 1000 h is about 9% of the tensile strength at 800 oC. Failure patterns of both shear and tensile joint specimens are similar regardless of the creep rupture time. Cracks initiate at the interface between the spinel layer and chromate (BaCrO4) layer, penetrate through the BaCrO4 layer, and propagate along the interface between the chromate layer and glass-ceramic substrate until final fracture. Final, fast fracture occasionally takes place within the glass-ceramic layer.
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