Vacuum Heat Treatment Knowledge

1. Nitrogen should not be used as cooling gas when titanium alloy is treated in vacuum furnace, because titanium and nitrogen react at high temperature to form golden titanium nitride.

2. All the movable connections of the vacuum furnace are sealed by O-ring, which is cooled by water.gas-turbine-vacuum-casting-technology

3. When the workpiece is quenched in vacuum, vacuum quenching oil should be used, which has lower saturated vapor pressure.

4. Vacuum furnace maintenance should be in the state of vacuum or pure nitrogen, to avoid suction and moisture absorption when not in use at ordinary times.

5. The pressure rise rate of domestic vacuum furnaces should not be less than 1.33Pa/h, and the standard of some foreign enterprises should be 0.67Pa/h.

6. Vacuum heating is mainly radiation, and the workpiece should be kept spacing in the furnace.titanium-alloy-vacuum-melting

7. During the heating process, the workpiece and the material in the furnace will deflate and the vacuum will decrease.

8. The heating temperatures of vacuum tempering, vacuum annealing, vacuum solid solution treatment and vacuum aging are generally the same as those of conventional treatment.vacuum-heat-treatment-furnace-in-automobile-exhaust-gas-purifier

9. Vacuum tempering furnace should have quick cooling device. The pressure of cooling water should be greater than 0.2 Mpa and the flow rate should be adjustable.

10. Cooling gas: steel generally uses 99.995% pure nitrogen, superalloy 99.999% nitrogen or argon, titanium alloy 99.995% argon.

11. Warming up: After putting in the workpiece, it is usually pre-pumped to 6.67 Pa before heating up.aeroengine-vacuum-melting