Aluminum alloy refining degassing specifically refers to the removal of inclusions and gases in the aluminum alloy. Because this process is often carried out simultaneously, it is customary to collectively refer to this process as refining in production.
The high degassing efficiency can greatly reduce the waste caused by bubbles and inclusions and greatly increase the output. Online degassing is considered a very effective hydrogen removal method. Due to the high vapor pressure of hydrogen, the dissolved hydrogen diffuses into the injected aluminum liquid gas. After the inclusions with a diameter of 10 microns come into contact with the bubbles, they will be adsorbed on the bubbles and float to the surface of the liquid.
Because aluminum alloy is easy to oxidize and absorb gas, its smelting process control is more complicated. Some alloying elements of aluminum alloy are easy to oxidize and cause oxidized inclusions. Unclean removal will reduce the mechanical properties. In production, the floatation method is often used, and the air bubbles are used to adsorb the oxidized impurities and particles to float up to purify the alloy liquid.
In order to reduce the phenomenon of pores caused by the inhalation of the alloy liquid, the oxidizing atmosphere must be avoided during the smelting process to avoid overheating of the alloy, and the refining shortens the smelting time and shortens the staying time at high temperature. The charge and tools used should be fully preheated to remove moisture, oil stains and rust. At the same time, the smelting process must have refining and degassing measures. At the same time, it is necessary to strictly manage the reheating materials. Do not melt alloys with large differences in composition in the same crucible. The ingredients must be accurate when melting aluminum alloys.
On-line degassing equipment is mainly used to treat molten aluminum containing a certain amount of hydrogen and other residues (alkali metals, slag inclusions),.
The Aluminum Alloy Refining Degassing principle of the online degassing equipment is the principle of air flotation. The process gas (inert gas or a mixture of inert gas and chlorine) is injected into the melt through the rotor, and the rotor is broken into uniformly dispersed tiny bubbles, and the tiny bubbles rise into the melt. On the surface, when the tiny bubbles rise, the task of removing hydrogen and impurities is completed.