During the casting process, the burning loss of molten aluminum is inevitable, but the resulting loss of metallic aluminum cannot be ignored. How to reduce the burning loss of molten metal becomes the key. It is necessary to strictly control the temperature of the molten aluminum, reduce the disturbance of the molten aluminum by improving the mixing method of the molten aluminum, organize production in a reasonable and compact manner, shorten the contact time of the molten aluminum with air, strengthen the maintenance of the casting equipment, maintain the operating conditions of the equipment, and realize the molten aluminum in the casting process The undercurrent movement of the aluminum alloy will have a significant effect on effectively reducing the burning loss of the molten aluminum during the casting process.
How to Reduce the Burning Loss of Molten Aluminum During Casting?
(1) Strictly control and promptly process the temperature of the raw aluminum liquid to meet the needs of casting production. After the molten aluminum with a higher temperature is injected into the mixing furnace, the cold material is added in time to reduce the temperature of the molten aluminum to 730 ℃, which can effectively reduce the influence of temperature on oxidation burnout.
(2) Try to shorten the residence time of molten aluminum in the mixing furnace.
(3) Strengthen the management of refining agents, master alloys, and other charge materials, prevent impurities from being mixed into the charge materials, ensure the cleanliness of the charge materials, and reduce the generation of metal and non-metal oxides during the smelting process.
(4) Electric energy is used as the heat source for the mixing furnace.
(5) Improve the stirring method of molten aluminum. In the implementation of “closed-door stirring” operation, the amount of disturbance of the molten aluminum is much smaller than that of mechanical stirring, which reduces the contact between the molten aluminum and the air during stirring. It can not only reduce the oxidation reaction between air and molten aluminum, but also reduce the inhalation of hydrogen by the molten aluminum, and keep the solubility of hydrogen in the molten aluminum to a minimum. It is not only conducive to the improvement of product quality, but also can effectively reduce the burning loss of molten aluminum.
(6) Use DC launders as much as possible, reduce unnecessary bends, and make the length of the working line of the runners as short as possible. Cover the flow cell with aluminum silicate fiber board.
(7) In view of the excessive drop from the chute to the ladle, the molten aluminum will form a turbulent flow when entering the boat-shaped ladle. You can consider installing a vertical pipe at the aluminum outlet of the chute to control the generation of turbulence and make the molten aluminum The contact with air is reduced during the descending process, reducing the oxidation of molten aluminum.
(8) Improve operation quality and reduce metal loss in the production process. Operators should pay attention to the angle and use of the shovel, minimize the disturbance of the liquid surface of the molten aluminum by human factors, keep the integrity of the aluminum oxide film on the liquid surface as much as possible, prevent the molten aluminum from splashing, and reduce the secondary impact of the molten aluminum.
(9) Improve the maintenance and repair quality of casting equipment, keep the equipment running smoothly, reduce equipment vibration and tilt to a minimum, control the size of aluminum ingots during casting, ensure the casting yield rate, and reduce the scrap rate in the production process. Reduce the return rate and control the burnt loss of the cold material caused by the waste.
(10) Timely recovery and sorting of waste products, splashed aluminum and residual aluminum in the slagging oxide slag produced during the production process, and adding them to the mixing furnace in an appropriate way for re-smelting is also a way to reduce the burning loss of molten aluminum.