High accuracy interface characterization of three phase material systems in three dimensions

• Published in: Journal of power sources 2010-12, Vol.195 (24), p.8168-8176
• Main Authors: Jørgensen, P.S., Hansen, K.V., Larsen, R., Bowen, J.R.
• Format: Article
• Language: English
• Subjects: Applied sciences; Boundaries; Direct energy conversion and energy accumulation; Electrical engineering. Electrical power engineering; Electrical power engineering; Electrochemical conversion: primary and secondary batteries, fuel cells; Energy; Energy. Thermal use of fuels; Equipments for energy generation and conversion: thermal, electrical, mechanical energy, etc; Exact sciences and technology; Fuel cells; Interface characterization; Mathematical analysis; Microstructure; Phase boundaries; Solid oxide fuel cells; Surface area; Three phase; Tomography; Triple phase boundary; Two phase
• ISSN: 0378-7753; 1873-2755
• DOI: 10.1016/j.jpowsour.2010.06.083

Quantification of interface properties such as two phase boundary area and triple phase boundary length is important in the characterization of many material microstructures, in particular for solid oxide fuel cell electrodes. Three-dimensional images of these microstructures can be obtained by tomography schemes such as focused ion beam serial sectioning or micro-computed tomography. We present a high accuracy method of calculating two phase surface areas and triple phase length of triple phase systems from sub-voxel accuracy segmentations of constituent phases. The method performs a three phase polygonization of the interface boundaries which results in a non-manifold mesh of connected faces. We show how the triple phase boundaries can be extracted as connected curve loops without branches. The accuracy of the method is analyzed by calculations on geometrical primitives.