Porcelain stoneware consolidation by flash sintering

Porcelain stoneware was consolidated by flash sintering under DC polarization using current densities in the range 4‐20 mA/mm2. The results show the applicability of this innovative sintering technology to a material whose densification occurs by vitrification, thus allowing to extend the possible application field of flash sintering to traditional ceramics. Using appropriate current density, the flash‐ sintered samples are dense, homogeneous, and well‐vitrified. XRD and microstructural analysis points out the formation of primary mullite while secondary mullite is only sporadically observed. In addition, comparison between flash sintering and fast firing shows that the densification obtained in the selected ceramic system via the former route cannot be reproduced just by a rapid heating process.