Aluminum, primary aluminum, electrolytic aluminum, aluminum ingots, alumina introduction and differences

[China Aluminum Network] Electrolytic aluminum is a method of smelting metallic aluminum, and aluminum oxide is generally decomposed into metallic aluminum by a large current in an electrolytic cell.

Aluminum ingots are divided into high-purity aluminum ingots, aluminum alloy ingots and remelted aluminum ingots according to different components; they can be divided into round ingots, plate ingots, bar ingots, and T-shaped ingots according to their shapes and sizes.

Aluminum is a silver-white metal, and its content in the earth's crust is second only to oxygen and silicon in third place. Aluminum has a low density and is called light metal. Aluminum is a non-ferrous metal with high output and usage. It is second only to steel in the world. The density of aluminum is about 1/3 of that of steel and copper. Due to the lightness of aluminum, it is commonly used in land, sea, and air transportation in manufacturing, trains, subways, automobiles, airplanes, ships, and rockets to reduce its own weight and increase its load. Similarly, aluminum has a significant position in military products.

Aluminum oxide, also known as aluminum oxide, is a white powder. Primary aluminum is a liquid aluminum liquid that is extracted during electrolysis and has not been treated by precipitation or the like. The primary aluminum can be used as an aluminum ingot by in-body cooling of the aluminum ingot model. Therefore, alumina is a raw material for the extraction of aluminum liquid, electrolytic aluminum is a process, and primary aluminum is an aluminum liquid in an electrolytic process, and an aluminum ingot is an aluminum product, which is a saleable product that is finally sold in the market.

Electrolytic aluminum is aluminum obtained by electrolysis. The modern electrolytic aluminum industry uses cryolite-alumina molten salt electrolysis. Molten cryolite is a solvent, alumina as a solute, carbon body as an anode, and aluminum as a cathode. After a strong direct current is passed, an electrochemical reaction is performed at two poles in the electrolytic cell at 950°C-970°C. Both electrolytic.

Industrial aluminum ingots

In our daily industrial raw materials called aluminum ingots, according to national standards (GB/T 1196-2008) should be called "remelting aluminum ingots", but everyone used to call "aluminum ingot." It is produced by electrolytic method using alumina-crylylite. There are two major categories of aluminum ingots after they have entered industrial applications: cast aluminum alloys and deformed aluminum alloys. Foundry aluminum and aluminum alloys are castings that produce aluminum by casting; deformed aluminum and aluminum alloys are processed products that produce aluminum by pressure processing methods: plates, strips, foils, tubes, rods, patterns, wires, and forgings. According to national standards, "remelting aluminum ingots are divided into eight grades based on chemical composition, namely Al99.90, Al99.85, Al99.70, Al99.60, Al99.50, Al99.00, Al99.7E, Al99. 6E" (Note: The number after Al is aluminum content). Some people call "A00" aluminum, which is actually 99.7% pure aluminum, and is called "standard aluminum" in the London market. Everyone knows that China’s technological standards in the 1950s came from the former Soviet Union. “A00” is a Russian trademark in the Soviet Union’s national standards. “A” is a Russian alphabet, not the English “A”, and it is not a Chinese phonetic alphabet. "A" is in line with international standards, saying "standard aluminum" is more accurate. Standard aluminum is an aluminum ingot containing 99.7% aluminum, which is registered in the London market.

Alumina (Al2O3) is a high hardness compound with a melting point of 2054°C and a boiling point of 2980°C. It is an ionizable ionizable crystal at high temperatures and is commonly used in the manufacture of refractory materials. Industrial Al2O3 is prepared from bauxite (Al2O3 • 3H2O) and diaspore. Al2O3 with high purity is generally prepared by chemical methods.

Al2O3 has many isomorphous crystals, and there are currently more than 10 known, mainly three crystal forms, namely γ-Al2O3, β-Al2O3, α-Al2O3 (corundum). The structure differs in its nature and is almost completely converted to α-Al2O3 at high temperatures above 1300°C.