ABSTRACT

metal supported solid oxide fuel cells (PMS-SOFCs) are regarded as a promising choice for power generation. 430 L steel is a popular choice for SOFC support due to its acceptable electrical performance and stability while offering very-low cost. In this study, we investigate the oxidation kinetics of 430 L porous support and interface between anode and support of plasma sprayed PMS-SOFCs in air at 650°C. The effect of exposure time on the microstructure and phase is studied. The metal support has a mass gain of ~1% after 500 h exposure because a continuous Cr₂O₃ scale formed. The element diffusion across the interface of anode and support is characterized. Thin and continuous scales are found at the interface and hinder the diffusion of Cr. The thickness of oxide scale and Cr diffusion distance is less than 1 μm after 500 h oxidation. In general, the oxidation at 650°C is found to be acceptable. Moreover, a decrease of maximum power density from 0.47 to 0.40 W cm⁻² at 650^°C is found after 500 h oxidation, indicating that sacrificing 16% of initial power density could acquire a continuous Cr₂O₃ scale. The increase of ohmic and polarization resistance should be the reason to the cell performance degradation.

摘要

金属负载固体氧化物燃料电池（PMS-SOFCs）被认为是一种很有前途的发电选择。430 L 钢因其可接受的电气性能和稳定性而成为 SOFC 支撑的热门选择，同时成本非常低。在这项研究中，我们研究了 430 L 多孔载体的氧化动力学，以及在 650°C 的空气中等离子喷涂 PMS-SOFC 的阳极和载体之间的界面。研究了暴露时间对显微组织和相的影响。金属载体在暴露 500 小时后质量增益约为 1%，因为连续的 Cr ₂ O ₃规模形成。表征了穿过阳极和载体界面的元素扩散。在界面处发现了薄而连续的鳞片，阻碍了铬的扩散。氧化500 h后氧化皮厚度和Cr扩散距离小于1 μm。通常，发现在 650°C 的氧化是可以接受的。此外，氧化500 h后，在650 ^° C下最大功率密度从0.47下降到0.40 W cm ^-2，表明牺牲16%的初始功率密度可以获得连续的Cr ₂ O ₃标度。欧姆和极化电阻的增加应该是电池性能下降的原因。