Flash sintering is a “low power” process where the application of modest electrical fields at low current densities can produce sintering in mere seconds at furnace temperatures that are several hundred degrees below conventional manufacturing processing temperatures. Dramatic reductions in energy consumption and rapid, continuous manufacturing of ceramics appear feasible.

The first experimental results on flash sintering show that 3-mol%-yttria-stabilized zirconia sinter in a few seconds at 850°C under an electric field of ~120 V˙cm–1 (Figure 1).¹ This abrupt sintering transition, called flash sintering, is accompanied by a sudden increase in conductivity of the specimen. The generality of this phenomenon, which also has been demonstrated for several oxides² and silicon carbide,³ is remarkable. A similar phenomenon occurs in oxide glasses, where applying an electrical field induces fluidity below the softening temperature, also with a simultaneous and abrupt increase in electrical conductivity.⁴