Discover the history
In 1808, the British chemist David H. Davy made a magnesium amalgam by electrolyzing the mixture of mercury and magnesium oxide, and obtained magnesium metal for the first time. Magenesium is the city name of Greece, where David made magnesium metal. In 1828, the French scientist ABI Bussy used potassium to reduce the melting of magnesium oxide to obtain magnesium metal. In 1833, the British scientist M. Faraday made magnesium metal by electrolysis of magnesium oxide. In 1886 Germany used this method for industrial production.
â– The nature of magnesium
Magnesium is one of the most abundant light metal elements on the earth. Magnesium has a specific gravity of 1.74g/cm3. It is only 2/3 of that of aluminum, 2/5 of titanium, and 1/4 of steel. Magnesium alloy is 36% lighter than aluminum alloy. It is 73% lighter than zinc alloy and 77% lighter than steel. Magnesium has high specific strength, specific rigidity, good thermal and electrical conductivity, and good electromagnetic shielding, damping, vibration reduction, cutting processability, low processing cost, processing energy of only 70% of aluminum alloy, and easy recovery. advantage. The specific strength of magnesium alloy is higher than that of aluminum alloy and steel, and slightly lower than that of fiber reinforced plastic with the highest specific strength. The specific rigidity is much higher than that of aluminum alloy and steel, which is much higher than that of fiber reinforced plastic. The wear resistance is much better than that of low carbon steel. Has exceeded the die-casting aluminum alloy A380; damping performance, magnetic shielding performance is much better than aluminum alloy.
â– Magnesium Resources
Magnesium is an important non-ferrous metal with limited distribution in the natural world. It is a divalent alkaline earth metal, accounting for approximately 2.35% of the earth's crust quality. Magnesium is rich in resources and has many types. The most important are magnesium chloride and carnallite in seawater, salt lake brine, and magnesite and dolomite in the form of carbonates.
â– Preparation of Magnesium
The current production methods of magnesium metal can be divided into two major categories, molten salt electrolysis and thermal reduction. At present, magnesium produced by these two methods accounts for about 80% and 20% respectively. Specific methods are: molten salt electrolysis method of magnesium, silicon thermal reduction method of magnesium. Molten salt electrolysis of magnesium includes the production of magnesium oxide and the electrolysis of magnesium. Two major methods are used in the silicon thermal reduction method, namely the Pidgeon method (Pirgian method) and the Magnitt method.
â– Use of magnesium
Magnesium is mainly used for the manufacture of aluminum alloys, and magnesium as an alloying element can increase the mechanical strength of aluminum, improve the mechanical processing performance, and the alkali corrosion performance. Because magnesium alloys (including aluminum, manganese, zinc, lithium, etc.) have higher specific strength (strength per unit of mass) of structural parts or die-cast parts, in the automotive, aerospace, aerospace, etc. industries, replacing part of aluminum with magnesium can reduce The quality of the structure. Magnesium and halogens have strong affinity, and are important reducing agents for the production of titanium, zirconium, hafnium, uranium, and thorium by the metal thermal reduction method. Magnesium can be used as a nodularizer for producing nodular cast iron. In the iron and steel smelting, magnesium can replace the calcium carbide desulfurization, so that the sulfur content in the steel can be reduced even lower, and the usage in this area increases rapidly. In organic synthesis, the Grignard reaction of magnesium can be used to synthesize a variety of complex organic compounds. Magnesium is also used as anode material for cathodic protection in chemical tanks, underground pipelines, and hulls; magnesium is used to make dry batteries and magnesium-water storage batteries. Because of its high combustion heat, magnesium emits dazzling brilliance when it is burned. It is also used to make lighting flares, incendiary bombs, and fireworks. In addition, magnesium can also be used as a new energy storage material, storing 19 x 109 joules per cubic meter of MgH2.