Ultra high temperature rapid cycle induction furnace

摘要

An induction furnace that has a plurality of high temperature electrically conductive ceramic electrodes having no connecting electrical lead (leadless electrode). The leadless electrodes are exterior to and proximate a working furnace space. At least one metallic electrical conductor surrounds but is not connected to the ceramic electrodes and a power supply is connected to the at least one electrical conductor so that activation of the power supply creates an alternating current through the electrical conductor of sufficient energy to create an electromagnetic flux of sufficient flux density to heat the at least one ceramic electrode to a temperature in excess of about 1700° C. to heat the space. A very high temperature furnace for operation in air is included within the invention wherein electrodes proximate the working furnace space are made of a high temperature, stable, electrically conductive metal oxide and at least one intermediate leadless electrode is provided sufficiently near the proximate metal oxide (e.g. zirconia) ceramic electrodes to heat the proximate metal oxide ceramic electrodes above their electrical conducting temperature so that they conducts sufficient current to maintain their own temperature. The intermediate ceramic electrodes can then be withdrawn. The invention further includes the method of heating a material to high temperature using the furnace of the invention.