Nature and Usage of Magnesium


Magnesium is one of the lightest structural metal so far known in the world. Besides its light-weight construction, a few of the other advantages it offers are: high specific strength and stiffness, excellent damping and cutting properties, and easy recycling. Magnesium alloy is internationally used in the automotive industry to remove weight, save energy, reduce pollution and improve the environment. Automotive fuel consumption per hundred kilometers will eventually be reduced to 3L in developed countries, and magnesium consumption in European automotive industry accounts for 14% of the total consumption of magnesium. It is expected to increase15-20% annually in the future, achieving 200,000 tons in 2005.

Compared with plastics, magnesium alloy comes with lighter weight and higher strength, also it has better vibration and thermal fatigue resistance, better thermal conductivity and electromagnetic shielding ability, and excellent casting process performance, especially it is unproblematic for recycling. Thus all these contribute to its replacement of steel, aluminum and plastic and becoming a new generation of high-performance organizational material. To meet the high integrating, lighter and smaller trend of electronics and telecommunications devices, magnesium alloy can be the ideal housing material for products concerning with traffic, electronic information, communications, computers, audio-visual equipment, hand tools, electrical machinery, forestry, textiles and nuclear power plant. Developed countries usually attach great importance to the development and application of magnesium alloy, especially its application in producing auto parts, laptop computers and other portable electronics. With the amazing trend of 20%’s annual growth rate, it indeed is developing compellingly.

Magnesium is a major component in aluminum alloys. The world’s yearly demand is about 15 million tons. China’s annual aluminum alloy output is 2.9 million tons in 2000, among which about 10,100 tons of magnesium are needed. With the increasing demand for high-strength and low-sulfur steel in auto industry, natural gas pipelines, offshore drilling platforms, and bridges, buildings constructions during recent years, many Chinese steel mills have started producing high-quality steel using magnesium powder to achieve deep desulfurization. Magnesium powder has a rather promising market for steel desulfurization. In addition, it can also be applied in manufacturing chemical products, medicines, fireworks, signal flares, metallic reducing agents, paint, welding wire and agents for nodular cast iron.

Magnesium metal powder is the powder form of elemental magnesium. It is soluble in mineral acids, concentrated hydrofluoric acid, ammonium salt and hot water. Mainly magnesium powder can be prepared by the electrolysis of molten magnesium chloride and dehydrated carnallite. Magnesium powder can be very explosive and it contributes high temperature and dazzling white light when it burns. This is also why magnesium has a wide range of uses in the military and aerospace industry. For example, working as the rocket ramjet and removal of propellant gas. Besides that, magnesium powder can also be used as cleaning and reducing agents in the steel industry and non-ferrous metal casting, while the reducing agent for rare metal production. In the chemical industry, magnesium powder is becoming more and more popular as it can be used for spraying, coating, and anti-corrosion. It can also be very useful in monocrystalline silicon, polycrystalline silicon and metallurgy powder casting.

Modern warfares are demanding on military’s remote rapid deployment capacity, requiring the increasing use of light metals in handheld weapons, armored vehicles, trucks and aviation guided weapons. Weight reduction is the main move to improve the operational performance of weaponry. Therefore the lightweight characteristic of magnesium has determined aluminum alloy to be the indispensable structural material for spacecraft, military aircraft, missiles, high mobility vehicles and vessels. This also can illustrate the national defense needs of vigorous advance of magnesium alloy application scope.