Nowadays, special-shaped aluminum rods are gradually becoming more widely used and are used in aerospace, transportation, electronic home appliances, etc. However, the production of special-shaped aluminum rods will contain some impurities. So how to remove the impurities in special-shaped aluminum rods? Woolen cloth? The following editor will bring you a method to remove impurities in special-shaped aluminum rods.
Adding some chlorine gas in production can effectively solve this problem. Adding some chlorine gas during production can chloride some elements that are more electronegative than aluminum, and at the same time make the aluminum rods flush with nitrogen. At the same time, non-metallic inclusions and dissolved hydrogen in the aluminum liquid are removed, and then passed through Continuous elimination allows fine nitrogen bubbles to be evenly distributed in the treated aluminum liquid, thereby eliminating impurities.
Good special-shaped aluminum rods can not only improve the quality of the project, but also extend the service life of the project, so be careful when selecting special-shaped aluminum rods.
Smelting of aluminum alloy
Smelting is to provide ingots for plastic processing. Smelting furnaces mostly use gas-fired reverberatory furnaces or oil-fired reverberatory furnaces, with a general capacity of 20 to 40 tons or more; resistance heating reverberatory furnaces are also used, with a capacity of generally about 10 tons. In order to shorten the furnace loading time, improve melting efficiency, and reduce gas absorption and oxide film involvement, tilting top-loading circular furnaces have been adopted in industry. It is best to use rapid analysis instruments to analyze the alloy composition during smelting and make timely adjustments. In order to ensure the purity of the melt, prevent the pollution of harmful gases and control the chemical composition, in addition to shortening the smelting time as much as possible, it is advisable to cover it with powdery flux mainly composed of potassium chloride and sodium chloride. The general dosage is 0.4 to 0.4% of the weight of the charge. 2%. The melting temperature is usually controlled at 700~750℃.
The melted metal also needs to be refined and filtered to remove harmful hydrogen gas and non-metallic inclusions in the metal to improve the purity of the metal. Refining usually uses solid refining agents or gaseous refining agents. Solid refining agents are generally based on chlorine salts, and refining agents that use hexachloroethane instead of chlorine salts are also used. In the early days, highly active chlorine was used as a gas refining agent. Although the purification effect was good, it caused serious environmental pollution. Therefore, nitrogen-chlorine mixed gas, inert gas and three-gas refining agent were developed, which have better effects. In order to ensure the refining effect, the oxygen and moisture contents in the refining gas should generally be less than 0.03% and 0.3 g/m3 respectively. The dynamic vacuum degassing method also has good degassing and sodium removal effects.
Filtration is to pass the molten metal through a filter made of neutral or active materials to remove suspended inclusions in the melt. Glass mesh, microporous ceramic tubes and plates, and alumina particles are commonly used as filter beds for filtration. Electric flux refining and flux layer filtration can also be used.
