VACUUM HEAT TREATMENT DEVICE

PURPOSE:To cool and harden uniformly and quickly a material to be treated after heating and to produce a heat-treated product having good quality by providing a heating chamber, gas cooler for cooling the material to be treated and fan for circulating a cooling gas in a vacuum heat treatment furnace. CONSTITUTION:The heating chamber 6 consisting of a heat insulating material 5 such as carbon fibers is disposed in a vacuum tank 1 and a rotatable stage 17 on which the material A to be treated is imposed is placed thereon. The gas cooler 7 and the fan 8 for circulating the gas are installed behind the chamber 6. The inside of the vacuum tank is evacuated to a vacuum through a discharge port 4 and thereafter the material to be heated on the rotating stage 17 is heated to the intended temp. by the heater 9 in the chamber 6. Gas such as N2 is introduced through a gas introducing port 3 into the chamber and is cooled by the cooler 7. The cooling gas is circulated by the fan 8 so as to pass through an inlet 11 to an outlet 12 of the chamber 6, by which the material A is quickly and uniformly cooled and hardened. The material is thus heat- treated to the product having good quality without uneven hardening.