Basic knowledge of experimental resistance furnace:
1. nitrogen should not be used as cooling gas when titanium alloy is treated in experimental electric furnace, because titanium and nitrogen react at high temperature to form golden titanium nitride.
2. all the movable connection parts of the experimental electric furnace are sealed with O-shaped rubber rings, and this part is cooled with water.
3. when the workpiece is quenched in vacuum, vacuum quenching oil with low saturated vapor pressure shall be used.
4. the maintenance of the experimental electric furnace should be in the vacuum or pure nitrogen state to avoid inhaling air and moisture when not in use.
5. the pressure rise rate of domestic experimental electric furnace shall not be greater than 1.33pa/h, and the standard of some foreign enterprises is 0.67pa/h
6. vacuum heating is dominated by radiation, and the distance between workpieces in the furnace shall be maintained.
7. during the heating process, the workpiece and materials in the furnace will be vented, which will reduce the vacuum degree.
8. the heating temperature of vacuum tempering, vacuum annealing, vacuum solution treatment and vacuum aging is generally the same as that of conventional treatment.
9. the vacuum furnace shall be equipped with quick cooling device. The pressure of cooling water shall be greater than 0.2MPa and the flow shall be adjustable.
10. cooling gas: 99.995% nitrogen is generally used for steel, 99.999% nitrogen or argon is used for high-temperature alloy, and 99.995% argon is used for titanium alloy.
11. temperature rise: after the workpiece is put in, the temperature can be raised and heated only when it is pre pumped to 6.67pa