A microwave furnace has a furnace chamber formed between a chamber housing and a sintering platform for an object to be sintered. A microwave source is arranged for emitting microwaves into the furnace chamber. The microwave furnace further has a susceptor that comprises a material which over a temperature range of the material of at least 23 C to 700 C couples into microwaves. The susceptor and the furnace chamber are movable relative to each other between a first position, in which the susceptor is positioned relative to the furnace chamber, and a second position in which the susceptor is positioned further retracted from the furnace chamber relative to the first position. The invention helps providing a zirconia material with a relative homogeneous material structure.

A furnace system includes a heating chamber, a retort assembly, and a waveguide. The heating chamber includes a shell encompassing an insulation layer and a working volume, where the working volume is configured to receive at least one part for heat treatment. The retort assembly is supported within the insulation layer and includes an inner retort surface facing the working volume. The inner retort surface is formed of at least one carbon compound reflective of microwave radiation, and the retort assembly defines a retort aperture. The waveguide is configured to direct microwave radiation from a microwave source to the retort aperture.

The present invention relates to a microwave melting apparatus and system for investment casting the metals obtained therefrom. In addition to enhanced production capacity, the system allows for the use of both a broad range of metal alloys and a variety of forms including ingot, scrap, granulated and powdered metals not possible with induction systems generally.

A process for direct reduction of iron ore in a solid state includes exposing briquettes of iron ore fragments and biomass to electromagnetic energy under anoxic conditions and generating heat within iron ore in the briquettes. The iron ore is reduced in a solid state within the briquettes, and the biomass provides a source of reductant.

An apparatus is provided for heating plastic preforms, having a plurality of resonator units, into which in each case plastic preforms can be introduced in order to heat the latter, having at least one microwave generating unit for generating microwaves, and having a feed device for feeding to at least one resonator unit the microwaves generated by the microwave generating unit, and having at least one rectifier unit for providing a rectified voltage. Further, at least one rectifier unit provides voltage for operating at least two resonator units.

A process for direct reduction of iron ore in a solid state is disclosed. The process operates under anoxic conditions with biomass as a reductant and with electromagnetic energy as a source of heat.

A microwave furnace includes a microwave casket having an inner surface forming an internal cavity. A heatable body, formed at least in part of a microwave susceptor material, is located in the internal cavity of the casket and heats in response to a microwave field. A thermal control system is provided, which includes a fluid flow path extending through the casket and has an inlet and an outlet formed in the microwave casket. A portion of the fluid flow path is adjacent the heatable body. The thermal control system flows a thermal transfer fluid through the fluid flow path via the inlet to absorb heat from the heatable body and to transfer the absorbed heat along the fluid flow path until the thermal transfer fluid exits the fluid flow path via the outlet.

A method for at least locally increasing the plasticity of a metal workpiece, which contains in particular an aluminum alloy, wherein the workpiece is irradiated in order to increase its temperature, and an associated production device, is provided. In order to be able to more quickly and thoroughly heat specific regions of a metal workpiece than other regions in a targeted manner, wherein it is possible to heat these regions more quickly and thoroughly with the same radiation output, while the surface of the workpiece remains largely unaffected, it is proposed that an absorbent be applied at least locally to the workpiece prior to irradiation thereof, wherein the degree of absorption of the absorbent for the radiation is greater than the degree of absorption of the workpiece for the radiation.

A microwave heating apparatus according to the present disclosure includes a housing, a drum unit disposed rotatably on the housing and into which heating target substance and gas are introduced, and at least one heating unit heating the drum unit by applying microwaves to the drum unit. With a microwave heating apparatus and a method for manufacturing an aluminum nitride using the same of the present disclosure, an aluminum nitride may be manufactured at a lower temperature than that of conventional methods, thereby reducing manufacturing time. Additionally, a microwave heating apparatus according to the present disclosure may significantly reduce power consumption compared to an electric heating apparatus.

A microwave reduction furnace including a reaction furnace provided with a refractory chamber of silica or silicon carbide for storing a material therein, a supply section for supplying the material into the refractory chamber, the material being a mixture of a silica powder and a graphite powder or a mixture of a silica powder, a silicon carbide powder and a graphite powder, a discharge section for discharging molten silicon, obtained through reduction, out of the chamber, and a microwave oscillator for outputting microwave toward the refractory chamber in the reaction furnace with a degree of directionality by virtue of a helical antenna or a waveguide.