Aluminum is a silver-white metal and ranks third in the earth's crust after oxygen and silicon. The density of aluminum is relatively small, only 34.61% of iron and 30.33% of copper, so it is also called light metal. Aluminum is a non-ferrous metal whose output and consumption are second only to steel in the world. Because aluminum is light, it is often used in the manufacture of land, sea and air vehicles such as automobiles, trains, subways, ships, airplanes, rockets, and spacecraft to reduce its own weight and increase the load.
The raw material in our daily industry is called aluminum ingot. According to the national standard (GB/T 1196-2008), it should be called "aluminum ingot for remelting". It is produced by the electrolysis method of alumina-cryolite.
The use of aluminum ingots: mainly used in die-casting alloys, battery industry, printing and dyeing industry, pharmaceutical industry, rubber industry, chemical industry, etc. Alloys of aluminum ingots and other metals are widely used in electroplating and spraying industries. Aluminum ingots refer to pure aluminum ingots, of course there are impurities, but as aluminum ingots, at least 90% purity.
Aluminum ingot has excellent resistance to atmospheric corrosion, so it is mainly used for surface coating of steel and steel structural parts (such as aluminized ingot), and is widely used in automobiles, construction, shipbuilding, light industry and other industries. In recent years, Western countries have begun to try to directly use aluminum ingot alloy plates as roof covering materials. Its service life can be as long as 120-140 years, and it can be recycled. However, the service life of using aluminized ingot iron plates as roofing materials is generally 5 -10 years.
Aluminum ingots have practical mechanical properties. The strength and hardness of the aluminum ingot itself is not high, but after adding aluminum, copper and other alloying elements, its strength and hardness are greatly improved, especially the emergence of aluminum ingot copper-titanium alloy, and its comprehensive mechanical properties are close to or reach aluminum alloy, The creep resistance of brass and gray cast iron has also been greatly improved. Therefore, aluminum ingot copper-titanium alloy has been widely used in the production of small hardware.
The aluminum ingot casting process uses molten aluminum inject into the mold, taken out after being cooled into a cast slab. The injection process is a key step for product quality. The casting process is also the physical process of crystallizing liquid aluminum into solid aluminum. The process of casting aluminum ingots is roughly as follows:
Aluminium tapping-slagging-weight inspection-ingredients-furnace loading-refining-casting- remelting aluminum ingots -finished product inspection-finished product weight inspection-storage
Commonly used casting methods are divided into continuous casting and vertical semi-continuous casting. Continuous casting can be divided into mixed furnace casting and external casting. All these methods use continuous casting machines. Mixing furnace casting is the process of casting molten aluminum into the mixing furnace, and is mainly used to produce remelting aluminum ingots and casting alloys. External casting is directly cast from the ladle to the casting machine, which is mainly used when the casting equipment cannot meet the production requirements, or the quality of the incoming materials is too poor to be directly into the furnace. Since there is no external heating source, it is required that the ladle has a certain temperature, generally 690-740℃ in summer and 700-760℃ in winter to ensure that the aluminum ingot has a better appearance.
Chemical composition | |
Al | 99.72 |
Si | 0.09 |
Fe | 0.19 |
Cu | 0.01 |
Zn | 0.02 |