Views: 2 Author: Site Editor Publish Time: 2021-05-31 Origin: Site
Vacuum electric arc furnace is an industrial furnace that uses this principle to smelt metals. In a vacuum environment, the electric arc furnace is a vacuum electric arc furnace. Vacuum arc smelting uses high current and low voltage, which is a short arc operation. Next, the engineer of the vacuum electric arc furnace manufacturer-Zhenwu Electric Furnace will share with you the working principle of the vacuum electric arc furnace.
The vacuum arc furnace is a gas arc discharge. The arc discharge shows that the voltage between the electrodes is very low, but the current through the gas is relatively large, and the temperature of the arc zone is very high (about 5000K). The large current density comes from thermionic emission and self-emission of electrons, that is, there is a layer of positive ions around the negative electrode, forming a strong electric field, so that the cathode automatically emits electrons. A large number of electrons collide with gas molecules between the two poles to ionize them, thereby generating more positive ions and secondary electrons. Under the action of an electric field, they collide with the cathode and anode respectively, generating high temperatures. The temperature of the cathode is lower than the temperature of the anode because part of the energy is used for electron emission. The high temperature is also caused by the recombination of some positive ions and electrons.
Vacuum electric arc furnace is an industrial furnace that uses this principle to smelt metals. In a vacuum environment, the electric arc furnace is a vacuum electric arc furnace. Vacuum arc smelting uses high current and low voltage, which is a short arc operation. Generally, the arc voltage is 22-65v, and the corresponding arc length is 20-50mm (the latter is a large ingot). Since the successful platinum wire smelting experiment in 1839, more than 100 years later, people began to study the smelting of refractory metals. In 1953, vacuum electric arc furnaces began to be used in industrial production. Until 1956, the United States and many European countries were still smelting titanium in non-expendable furnaces, and in 1955 began to use expendable furnaces to make steel. Around 1960, the weight of steel ingots produced by consumable furnaces had reached more than 30 tons and had begun to take shape. At present, the vacuum consumable furnace produced by Kangsai company can represent this development trend. In order to improve production efficiency and equipment utilization, the two furnaces share a set of main power supply, vacuum system and automatic control system.
Vacuum arc furnace heat treatment of workpiece (or material) in vacuum can increase the service life of tools and molds, without oxidation, decarburization, bright surface, small deformation, energy saving and pollution-free, and change the mechanical and metallurgical properties.
Advantages of vacuum melting furnace:
Vacuum melting furnace is mainly used for melting active and insoluble metals, hard alloys, magnetic materials and stainless steel. It is actually low pressure (decompression) smelting. The higher the degree of vacuum, the closer the distance to the neutral atmosphere, the less the chemical reaction of the material. Next, please let the professionals from the vacuum melting furnace manufacturer-Zhenwu Electric Furnace talk about the advantages of vacuum melting furnaces.
(1) Vacuum is conducive to the removal of adsorbed gas and obviously promotes the shrinkage in the later stage of smelting.
(2) Vacuum helps to remove impurities such as silicon, aluminum, magnesium, calcium and their oxides, and plays a role in purifying materials.
(3) Vacuum can improve the wettability of liquid phase smelting, which is conducive to the shrinkage during the smelting process and improves the structure of the alloy.
(4) Vacuum is an ideal inert gas. When other primary or inert gas is not suitable, or the material is easy to be decarburized and carburized, a vacuum melting furnace can be used.
(5) Reduce the pollution of products by harmful components (water, oxygen, nitrogen, etc.) in the atmosphere. For example, it is difficult to reduce the water content in electrolytic hydrogen to -40°C. In vacuum smelting, as long as it is within a few hundred Pa, the vacuum content is equivalent to the dew point of -40°C.