However, minor agglomeration is una

However, minor agglomeration is unavoidable. In general, a similar micro-structural characteristic was observed in these samples i.e. uniformly sized grains with high degree of grain close packing. Almost no abnormal grain growth was observed. Energy dispersive X-ray analysis (EDX) indicates that the dark grains are Al2O3 and MgO while the lighter grains are YSZ. For samples with nano-particle additives, very fine white particles were observed on the sample surface (Fig. 4b).