1. Since twentieth Century, magnesium alloys have been applied in Aeronautics and Astronautics. Because magnesium alloys can greatly improve the aerodynamic performance of aircraft and significantly reduce its structural weight, many components are made of magnesium alloys. Generally, magnesium alloys used for aviation are mainly sheet metal and extruded profiles, and a few are castings. Cast magnesium alloys with rare earth metals as the main alloying elements of electrical grade magnesium oxide can be used for a long time at 473 ~ 573K, which is very suitable for aviation applications. China has developed ZM3, ZM4, ZM6 and ZM9 series rare earth magnesium alloys, which can be used in the aerospace field. At present, magnesium alloys are widely used in aviation, including civil and military aircraft components, propellers, gearboxes, support structures, rockets, missiles and satellites. With the development of magnesium alloy production technology, the performance will continue to improve and the scope of application will continue to expand.
_Making automotive parts with magnesium alloys for automotive applications can significantly reduce vehicle weight, fuel consumption, reduce exhaust emissions, improve the integration of parts and improve the flexibility of automotive design. Nowadays, the scope of global air pollution is becoming wider and wider, and automobile exhaust accounts for 65% of the total air pollution. With the energy shortage and environmental pollution problems becoming increasingly prominent, automobile manufacturers all over the world are facing pressure to reduce emissions and save energy. Usually, the vehicle self weight is reduced by 10%, the fuel efficiency can be increased by 5.5%, and the exhaust emission will be reduced correspondingly. There are two ways to lighten the automobile, one is to optimize the structure, and the other is to choose lightweight materials. Aluminum alloys, plastics (resin matrix composites) and magnesium alloys are considered to be ideal materials. Magnesium alloy die casting is the lightest of all die casting alloys and the most competitive lightweight material for automobiles. It plays an important role in weight reduction and performance improvement of automobiles. A large number of magnesium alloy parts have been produced to replace plastic and aluminum alloys.
Even steel parts. The use of magnesium alloys in automobiles can be traced back to the 1930s, when Volkswagen introduced the Beetle, which consumed only 18 kg of magnesium alloys in its engines and transmission systems. In 90s, the application of magnesium alloys in automobiles increased significantly, and the world increased by about 20% per year. It is predicted that after entering the 21st world, magnesium alloys for automotive parts will grow by more than 15% because of the pressure of energy saving and environmental protection. Ford Motor Company Aerostar Mimi-Vans car's middle and rear seats (only more than 100 tons of AM60 magnesium alloy per year) Ranger light truck clutch body and brake pedal support bracket, General Motors cylinder head, oil filter shell and other 10 parts are made of magnesium alloy. Toyota and its affiliates took the lead in making steering wheel cores, keys, brake housing, dumping devices and other driving rod components from magnesium alloys. The steering wheel cores were made of AM series alloys (generally AM50 or AM60), while the other components were made of AZ91 alloy. At present, magnesium alloys have been widely used in automotive dashboard, seat bracket, gearbox housing, steering system components, hood, door, frame, engine cylinder and other parts in developed countries. The application of magnesium alloy castings with lighter specific gravity than aluminum alloy on 1/3 has increased greatly. In recent years, the application of magnesium castings on automobiles has been increasing by 20% every year. The magnesia castings of Audi A6 have reached 14.2 kg per car, and will be increased to about 80 kg in the future. The magnesium die castings of intake manifold have been produced by American General Motors and German Pearsburg. Renault has produced magnesium wheel castings, and Audi has used magnesium castings for the earliest time. Instrument panel skeleton, Benz was the first magnesium die-casting for the seat frame, and steering wheel using magnesium castings is the first Italian Fiat company. In 1998, Ford's P2000 model used magnesium die-casting wheels weighed 3.1 kg, about 5 kg lighter than steel stamping wheels. Six Ford foundries now supply magnesium castings, about 12,000 tons a year and 45,000 tons in 2004. At present, some famous-brand cars abroad are actively using magnesium alloys, and some appearance panels are also using magnesium alloys, Mercedes-Benz CLK is the world's first car with magnesium alloy doors.
_Motorcycle and bicycle application China is a big country of motorcycle production, consumption and export. With the increasingly stringent urban environmental protection laws and regulations, it has become an inevitable trend to change the low technical content of conventional fuel motorcycles, bulky structural materials, excessive emissions, poor driving safety and other conditions. Chongqing University, Chongqing Magnesium Industry and Longxin Group have jointly produced nearly 10 magnesium alloy die-casting parts such as crankcase of Longxin LX150 motorcycle. A green concept vehicle of Longxin LX150 magnesium alloy is assembled with trial-produced magnesium alloy die-casting parts and squeeze casting wheels. The weight of the vehicle is 6 kg lighter than that of aluminum alloy casting vehicle. Bicycle is a new application area of magnesium alloy, mainly used for bicycle frame. Magnesium alloys have the advantages of being light, fast and comfortable, and having a mouth can make the tube diameter smaller, the tube wall thinner, and the frame stronger. The quality of the folding bicycle frame made of magnesium alloy is only 1.4kg.
_One of the representative equipment of wheelchair rehabilitation facilities is wheelchair. According to the quality, the wheelchairs on sale can be divided into standard type and lightweight type (aluminum alloy or titanium alloy). The materials used are steel tube, aluminum tube and titanium tube. AZ31 magnesium alloy is used to make wheelchair frame or other parts except wheels are basically made of magnesium alloy. The wheelchair can reduce weight by about 15%, which is light and flexible.
_Magnesium alloys used in shipbuilding industry and marine engineering are mainly used in navigation instruments, underwater weapons, seawater batteries, diving suits, sacrificial anodes, timing devices and so on. The most common application is magnesium aluminum zinc alloy.