The Usage of Magnesium and Other Aspects

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The Magnesium was first obtained by electrolyzing the mixture of Mercury and Magnesia by English chemists H.Davy in 1808. Magnesium is the name of one of the city in Greece and is also the place that Davy made Magnesium metal. In 1828, the French scientist A.A.B.Bussy obtained the Magnesium metal by using Potassium to smelt reduce the Mercury and Magnesia. In 1833, the English scientist M.Faraday also obtained the Magnesium metal by electrolyzing and fusing the Mercury and Magnesia. In 1886, the Germany used this method to begin the industrial production of Magnesium.

The Nature of Magnesium

Magnesium is one of the most abundant light metal elements in the earth. Its specific gravity is 1.74g/cm3 which is only the 2/3 proportion of Aluminum, 2/5 of Titanium and 1/4 of Steel. The Magnesium Alloy is 36% lighter than Aluminum Alloy, 73% lighter than Zinc Alloy and 77% lighter than Steel. Magnesium has its advantages of high specific strength and stiffness, good thermal conductive performance. It also has the advantages of good and low finished cost, only 70% processing energy of Aluminum Alloy, easy recycling, etc. The specific strength of Magnesium Alloy is higher than that of Aluminum Alloy and Steel which is also a little lower than the most specific strength fibre reinforced plastic. Its specific stiffness is the same as Aluminum Alloy and Steel, and is far higher than that of fibre reinforced plastic. Its wear-resisting property is better than that of low-carbon steel which has exceeded Die-casting Aluminum Alloy A380. Its vibration damping performance and magnetic shielding performance is far better than that of Aluminum Alloy.

The Resource of Magnesium

Magnesium is an important nonferrous metal which distributes widely in the nature. It belongs to bivalent alkaline earth metal and is about 2.35% of the mass of the earth crust. It has abundant resource and variety of kinds. The most important is magnesium chloride and brines, carnallite in sea water, and a carbonate form of magnesite and dolomite.

The Production Methods of Magnesium

There are two kinds of production methods of Magnesium metal in nowadays. They are molten salt electrolysis and thermal reduction methods. The Magnesium which is produced by these two methods is separately in 80% and 20%. The detailed methods are extracting Magnesium by molten salt electrolysis and thermal reduction. The two steps of Magnesium oxide production and electrolyzing extracting Magnesium are included in the molten salt electrolysis methods. The thermal reduction methods have two kinds of Pidgeon process and Magnetherm.

The Usage of Magnesium

Magnesium is mainly used in making Aluminum Alloy. It can enhance the mechanical strength and improve the mechanical processing performance and alkali corrosion as an alloying element. As the specific strength (strength per unit mass) of Magnesium Alloy (including the Aluminum, Manganese, Zinc, Lithium, etc.) structure or die casting is strong, it can reduce the mass of the structure by using Magnesium instead of partially Aluminum in the industry of automotive, aviation and aerospace. Magnesium has strong affinity with haloid which is an important reducing agent in producing titanium, zirconium, hafnium, uranium, beryllium by using metallothermics. Magnesium can be the nodulizing agent in producing the nodular cast iron. In the process of steel smelting, Magnesium can replace as calcium carbide desulphurization and it can also lower the containment of sulphur in the steel. The dosage of Magnesium in this aspect is growing rapidly. In the process of organic synthesis, by using the Grignard reaction of Magnesium, we can compound variety kinds of complicated organic compounds. Magnesium can be also used as the anode material of negative protection in the chemical tank, underground pipeline and hull. It can be used to make dry cell, Magnesium-seawater reserve cell. As the high combustion heat of Magnesium and its dazzling radiance when burned, it can be used to make flare, napalm bomb, fireworks, etc. Besides, Magnesium can also be used as a new kind of energy storage material which can store 19×109 J energy/cubic meter. Magnesium metal powder is widely used in the scientific area of army industry, aerospace industry and so on. It can also be used in the steelmaking and nonferrous metals cast as the desulfurizing agent and cleaning agent, the reduction agent in the production of rare metals. The application of Magnesium powder is increasing in the chemical industry, it can be used in the spray, paint and anti-corrosion industry as well as be widely used in the pressure cast of monocrystalline silicon, polycrystalline silicon and metallurgy powder.