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Abstract：
This work focuses in-depth on the quantitative relationships between primary first-order microstructural parameters (i.e., volume fractions of various phases and particle size distribution) with the more complex second-order topological features (i.e., connectivity of phases, three-phase boundary length (TPBL), interfacial areas, or tortuosity). As a suitable model material, a cermet nickel/samaria-doped ceria (Ni-SDC) is used as an anode in a solid oxide fuel cell (SOFC). A microstructure description of nano-sized Ni-SDC cermets, fabricated at various sintering conditions from 1100 °C to 1400 °C, was performed using FIB-SEM nanotomography. The samples were serially sectioned employing a fully automated slicing procedure with active drift correction algorithms and an auto-focusing routine to obtain a series of low-loss BSE images. Advanced image processing algorithms were developed and applied directly to image data volume. The microstructural-topological relationships are crucial for the microstructure optimisation and, thus, the improvement of the corresponding electrode performance. Since all grains of individual phases (Ni, SDC, or pores) did not percolate, special attention was given to the visualisation of the so-called active TPBL. Based on the determined microstructure characteristics of the prepared Ni-SDC cermets, including simulations of gas flow and pressure drop, thermal treatment at 1200 °C was recognised as the most appropriate sintering temperature.
摘要：
这项工作深入研究了一级微观结构参数之间的定量关系（即，各种相的体积分数和粒度分布)具有更复杂的二阶拓扑特征(即，阶段的连通性，三相边界长度（TPBL），界面面积,或弯曲)。作为合适的模型材料，金属陶瓷镍/samaria掺杂的二氧化铈(Ni-SDC)用作固体氧化物燃料电池(SOFC)中的阳极。纳米Ni-SDC金属陶瓷的微观结构描述,在1100°C至1400°C的各种烧结条件下制造，使用FIB-SEM纳米图谱进行。采用具有主动漂移校正算法和自动聚焦例程的全自动切片程序对样品进行连续切片，以获得一系列低损耗BSE图像。开发了先进的图像处理算法，并将其直接应用于图像数据量。微观结构-拓扑关系对于微观结构优化至关重要，因此，相应电极性能的提高。由于各个相的所有晶粒(Ni，SDC,或毛孔)没有渗滤，特别注意所谓的主动TPBL的可视化。基于所制备的Ni-SDC金属陶瓷的显微组织特征,包括气体流动和压降的模拟，在1200°C的热处理被认为是最合适的烧结温度。
