1. Quenching principle：
Vacuum quenching refers to a heat treatment method in which the processed workpiece is heated and insulated in a vacuum state, and then rapidly cooled in a high-pressure cooling gas to harden it. The operation process is usually as follows: load the workpiece into the furnace, vacuum, start heating when the vacuum degree reaches 1-10-2Pa, usually through preheating, so that the temperature of the workpiece is the same as the jealous temperature, and keep the temperature after reaching the solution temperature. After the heat preservation is completed, the furnace is filled with inert gas at a pressure of 2-10 bar, and the cooling gas is circulated between the workpiece and the heat exchanger with a fan to meet the requirement of rapid cooling from the solid solution temperature, so as to realize the hardening of the processed workpiece. Because vacuum high-pressure gas quenching has the advantages of high cooling rate, no surface oxidation, no carbon increase, good quenching uniformity, small workpiece deformation, high production efficiency, low cost, and no environmental pollution, its application is increasing day by day, and its development is quite rapid. It has become the most eye-catching vacuum heat treatment technology at home and abroad.
2. Quenching characteristics
The best effect of vacuum gas quenching is to make the processed parts get the most excellent mechanical properties, which must take into account the high cooling rate and good cooling uniformity. The cooling rate is simple to ensure the hardness of the processed part, and the cooling uniformity is good to ensure the smallest deformation. Because the vacuum heat treatment of metals and alloys is carried out under negative pressure, it is easy to obtain treatment effects that are not easy to obtain in general atmosphere heat treatment, so that the workpiece has excellent performance.
(1)No oxidation, no decarburization.
(2)Surface purification effect, the surface brightness of the workpiece is good.
(3)Less heat treatment deformation.
(4)Improve service life.
3. Main application
Mainly used for tools, molds, cutting tools and mechanical parts with relatively high technical requirements and complex shapes. The processed materials include W18Cr4V, W6Mo5Cr4VZ, Cr12, Cr12MOV, gCrsi, CrWMn, 3CrZWS, GCr15, 40Cr, 9Cr13, 3Cr13, 50CrV, 60512, 17-4PH, 15-7MOPH, ICr13NigTs, QBeZ and other materials. At the same time, machining or welding aluminum alloys and titanium alloys with complex shapes and high dimensional accuracy requirements also has the advantage of maintaining dimensional stability that other heat treatments cannot match.
4. Main configuration
· Work area size: 600mm (height) × 600mm (width) × 900mm (length)
· Bearing weight: 500Kg
· Working vacuum: 6.67×10-3Pa)
· Maximum temperature: 1300℃
· Temperature uniformity: ±5℃
· Temperature control accuracy≤±1℃
· Maximum inflation pressure: 10bar (absolute pressure)
· Cooling method: forced gas rapid cooling
