Cellular Automata Modelling of Microstructure Evolution of Ni Cermet Anode

The degradation of SOFC electrodes is largely determined by their microstructure changes. It is desirable that the microstructure evolution of electrodes in service can be simulated in 3-D for real materials so that the important parameters such as conductivities, TPB (triple phase boundary) density and tortuosity can be predicted. In this contribution a new cellular automaton based method of modelling microstructure evolution is presented. It is shown that the complex topological and morphological changes in a Ni-YSZ anode can be reproduced using this modelling method. The modelling results show that the microstructure evolution is sensitive to the wettability of Ni over YSZ. It is demonstrated that a good wettability is helpful in maintaining a slower coarsening rate and slower degradation rate of TPB density.