Critical assessment: electrical field/current application - a revolution in materials processing/sintering?

The interest towards field-assisted sintering techniques has been growing rapidly in the last 20 years, particularly in applications involving hard to sinter materials, such as nanocrystalline, refractory, and metastable materials. These techniques, in fact, allow obtaining the densification in conditions that are considerably milder than in traditional pressureless sintering or in hot-pressing. Despite this success, there is still a poor understanding of the involved basic mechanisms. In this assessment, all the main aspects associated with the use of these technique will be presented and discussed, with particular emphasis on spark plasma sintering.