Surface effects in field-assisted sintering

The more-stringent requirements for densification of new out-of-equilibrium powders have created a growing demand for nonconventional rapid sintering processes. Among those, field-assisted sintering techniques (FASTS) have seen a recent renewed interest motivated by their ability to consolidate a large variety of powder materials into high densities in short times. Characterization of a range of FAST-consolidated materials displayed relevant associated surface effects, such as grain boundary cleaning with direct grain-to-grain contact and advanced densification without sintering aids. These effects may be attributed to phenomena ranging from dielectric breakdown to a possible nonconventional plasma generation. Such surface effects provided a better intergranular bonding of powder particles during subsequent sintering.