本研究以鐵基(iron-based alloys)及鎳基(nickel-based alloys)為基底的金屬合金作為研究對象，其皆為固態氧化物燃料電池(SOFC)之金屬連接板候選材料，實驗是將材料置於SOFC運作的溫度800℃並通入空氣氣氛的操作環境下，比較材料之合金的高溫氧化行為、導電率與熱膨脹係數間的差異。 比較磁控濺鍍法(Plasma Sputtering)與網印法(Screen Printing) 兩種製程，並選擇Fe-Cr合金為底材，鍍上La0.7Sr0.3MnO3 (LSM)，探討於高溫時的氧化行為與高溫電性的作用。實驗結果顯示，合金鍍上LSM 於800℃空氣中200小時，因有LSM 層及界面間緻密氧化皮膜隔絕氧對合金底材的氧化，可有效降低氧化速率。合金底材與合金鍍上LSM 經800 °C 長時間1500hrs電阻量測，顯示合金鍍上LSM 的(ASR) 低於合金底材，其原因是Cr-Mn spinel 比例提高或二價金屬離子摻雜Cr2O3，提升了氧化層的導電性。因此LSM薄膜較適合做為高溫材料的保護膜，可有效降低材料高溫氧化造成材料效能的衰減，並適用於中低溫固態氧化物燃料電池(SOFC)。使用網印法於合金底材披覆La0.6Sr0.4Co0.2Fe0.8O3 (LSCF)，在800°C 測得的ASR 均低於披覆LSM 在同溫度下之ASR，合金/LSCF 用以作為金屬雙極板的材料，將可應用中低溫之固態氧化物燃料電池。 最後本研究探討密封材料與連接板接觸介面之高溫氧化行為分析。金屬基連接板材與封裝材料之熱膨脹係數、高溫穩定性及物化特性皆有不同的可靠性。因此調配出新的玻璃膠，其熱膨脹係數值於高溫(800℃)時熱膨脹係數值與其他Fe-Cr合金相當接近，應可防止熱應力對結構的破壞，與其他零組件的熱膨脹系數相當匹配，故可適用於SOFC電池堆之封裝。 根據本研究對陰極材料、玻璃膠結構、合金材料高溫氧化特性分析以及與合金測試結果，具鈣鈦礦結構之LSM、LSCF與玻璃膠應用於固態氧化物燃料電池之陰極材料與密封材料，應相當合適。 Ten iron-based alloys and nickel-based alloys were subjected to oxidation treatment in hot air environment for various period of time. All of them were alloys that can be applied to interconnect of solid oxide fuel cell (SOFC). The effect of La0.7Sr0.3MnO3 (LSM) coating on the oxidation behavior and electric properties of alloys were examined at fuel cell operation temperature in hot air. The LSM layer prevented oxygen react with the alloy, as a result the oxidation rate of the alloy with coated LSM are magnitude lower than those of alloy at 800℃ in air. After long-term electric resistance measurements at 800°C, ASR (area specific resistance) of the ally with coated layer is less than alloy. The reason is more Cr-Mn spinel layer formation and some divalent metal ions doped into chromium oxide. The alloy coated with LSM used for metallic interconnect is suitable for an intermediate-temperature SOFC. The alloy coated with La0.6Sr0.4Co0.2Fe0.8O3 (LSCF) sintering, the adhesion between the LSCF layer/alloy interface is excellent. After long-term electric resistance measurement, ASR for alloy coated with LSCF was less than for alloy coated with LSM. The LSCF used for metallic interconnect protective material could increase high temperature conductivity. Sealing glass over a long period of time during operation of a solid oxide fuel cell (SOFC) would generate thermal stresses in the seal and may have adverse effects on its mechanical performance. This may lead to cracking of the seal, resulting in mixing of the fuel and the oxidant gases.
