Using the flash sintering technique, cubic yttria‐stabilized zirconia is shown to sinter at 390°C, more than 1000°C below nominal sintering temperatures, by using a DC electric field of 2250 V/cm. Furthermore, flash sintering experiments performed with electric fields between 60 and 2250 V/cm were used to show that the relationship of the temperature at the onset of flash sintering (TOnset) and the applied field (E) follows the power relationship TOnset (K) = 2440 E−1/5.85(V/cm). Using this relationship, and considering the sintering of the sample in the absence of an electric field, the critical electric field to enter the flash sintering regime is shown to be 24.5 V/cm. For electric fields between this critical electric field and 2250 V/cm, the onset of flash sintering occurs in the same range of critical volumetric power dissipation, between 1 and 10 mW/mm3, suggesting this is a material property. Despite the volumetric power dissipation being the critical value for the onset of flash sintering behavior, the current density achieved during sintering appears to be more critical for densification rather than maximizing power dissipation.

Gadolinia-doped ceria ceramic pastes were formulated with different solid loadings and extruded using lab-scale equipment. The force to maintain a constant ram speed of 10 mm/min was recorded. The radial shrinkage after drying was proportional to the solid loading and this allowed the determination of the maximum solid loading by an extrapolation procedure. In order to obtain the apparent viscosity of the pastes, a novel approach based on the analysis of the slope of the extrusion pressure plot versus distance covered by the ram, was formulated for the direct determination of the shear stress upon extrusion. The agreement of the determined maximum solid loading with values calculated by two existing models confirmed that the proposed approach was an alternative and reliable method to identify the upper limit of the solid loading range for the formulation of extrudable ceramic pastes.

The conversion of silicon‐based polymers into a ceramic occurs by the release of small organic molecules at intermediate temperatures, and hydrogen at the higher temperatures. The conversion is accompanied by significant densification. In order for the body to emerge without fracture damage, the shrinkage must be accommodated by viscous flow. In this paper we show that the viscosity changes during the conversion, going through a sharp minimum near 600°C. In the regime of hydrogen evolution, which begins near 700°C, fairly steady viscous flow leads to large shrinkage. The viscosity increases rapidly as 1000°C is approached, pointing to the exhaustion of hydrogen. The results presented here may be used to optimize the time–temperature protocol for achieving damage‐free specimens: heating quickly up to ∼700°C and then slowly at higher temperatures to allow time for viscous relaxation.

SOFCs can be produced with a copper cermet anode using similar methods used with NiO-based anodes by a one-step firing procedure at relatively low temperatures, thus having cost and high energy savings. The use of copper can allow for the use of light hydrocarbons in the cell without external reforming equipment or need of high steam to carbon ratio, and without the risk of carbon deposition in the cell

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