Evidence for the microwave effect during hybrid sintering and annealing of ceramics
Since about 1970, there has been growing interest in the use of microwaves for heating and material processing. Microwave heating is fundamentally different from conventional heating in which electrical resistance furnaces are typically used. In microwave heating, heat is generated internally by interaction of the microwaves with the atoms and molecules of the material. Microwave heating has many potential benefits, such as rapid heating, selective heating and low cost [1, 2], these are attributable to the volumetric nature of microwave energy deposition. In addition to the possibility of faster and more controllable temperature ramp-up, microwaves can heat one region or phase more than others due to either the method by which the microwaves are deposited in the material or differences in the dielectric properties. The latter is important during the processing of new ceramic and composite materials. All the above can be treated as the thermal action of the electromagnetic field on matter.