本文主要研究在製作固態氧化物燃料電池(Solid Oxide Fuel Cell, SOFC)中電解質材料與黏結劑PVB間的熱解動力影響和最短的移除時間。由於製作的過程中添加高分子黏結劑,而黏結劑與電解質陶瓷材料熱解過程的影響,以PVB/陶瓷材料分別在氮氣與空氣下,依不同添加組成、以及不同操作溫度,分析其熱解時的反應動力。以熱重分析儀(Thermo-gravimetric analysis,TGA)觀察複合材料的熱重損失曲線,利用Arrhenius關係式,以等轉化率的原則,求得樣品的熱解動力參數。再由高分子黏結劑的熱解動力與胚體內黏結劑熱解產生氣體的質傳現象,建立三維氣體輸送模型,模擬氣體壓力在胚體內的變化與分佈情形,在不使陶瓷胚體產生缺陷的狀況下,設定陶瓷胚體發生破裂的最大壓力為限制條件,以最適化控制策略,尋求最佳升溫速率並使黏結劑燒除製程能在最短時間內完成。
The removal of PVB binder with ZrO2 and Y2O3 the electrolyte materials of Solid Oxide Fuel Cells (SOFCs) was studied. The kinetic equations of thermal degradation of PVB with different composition of ZrO2 and Y2O3 were determined. In addition, the minimum time required to remove the binder was calculated using a dynamic optimization stratagem. Kinetic parameters of the composite sample were estimated by thermogravimetry (TG) measurements and a non-linear heating algorithm. Results of the kinetic analysis revealed that the thermal degradation of PVB is affected by the present of the ceramics. The volatile gas evolved from the PVB thermal degradation can generate certain pressure inside the ceramic body. The build-up pressure distribution in the ceramic body described by the mass transport and the kinetic of thermal degradation models can be determined using numerical simulation. The pressure can affect the generation of the ceramic defects and have to be controlled by the heating conditions. The minimum time under constrains to remove the binder can be estimated by the dynamic optimization approach.