VACUUM FURNACE Russian patent published in 1995 - IPC

FIELD: chemical thermal treatment. SUBSTANCE: furnace has vacuum chamber with systems of vacuum air evacuation and working gas feeding and also heater, located inside vacuum chamber. Heater has integral-cold cathode, anode, one end fixed to vacuum chamber inner surface pipe of heat-resistant electrical insulating material and also screen. Screen is made optically low-transparent, transparent for electrons and is located between cathode and free end of pipe. Anode is located in pipe cavity in zone of pipe fixed butt. Pipe is located coaxially with anode and cathode. After vacuum chamber air evacuation, pressure is created in pipe cavity by working gas feeding system, under which vacuum-arc discharge existence is provided. Then direct current source voltage is applied to cathode and anode, that excite vacuum-arc discharge between cathode and anode. Heat energy of formed inside pipe gas column plasma is used to realize corresponding technological processes with pieces, located in vacuum chamber There are versions of furnace manufacture to realize technical processes, requiring lowered pressure in vacuum chamber relatively to pressure in pipe, and for realization of chemical-thermal treatment of pieces. EFFECT: vacuum furnace is used for chemical thermal treatment and pieces vacuum bake-out. 4 cl, 4 dwg