Aerospace applications of aluminum-lithium alloys

Aluminum-lithium alloy, aka Al-Li alloy , is the addition of a certain amount of lithium on the basis of aluminum, and it is generally used as aerospace aluminum. For the structure of the spacecraft, the reduction of the mass of the aluminum-lithium alloy plate can increase the payload, and each additional 1kg of the payload can bring benefits of $4,400 to $110,000. Therefore, due to the low density and good performance of Al-Li alloy, the Al-Li alloy structure is used in many spacecraft.

Aircraft manufactured by the Lockheed Missile and Space Corporation (LMSC) in the United States use low-density, medium-strength and high-stiffness materials, so Al-Li alloy products are widely used. Since the mid-1980s, a large number of 8090 and ordinary processing methods have been used to produce various forgings, thick plates, thin plates and extruded parts. LMSC uses 8090 plates on the Hercules payload adapter, reducing the mass by 180kg. The company's new space shuttle "ultralight tank," produced using AA2195 alloy, which is 47m long and 8.4m in diameter for holding cryogenic fuels and liquid hydrogen. The use of AA2195 alloy, the aerospace aluminum, reduced the fuel tank by 5% (nearly 3400kg), increased the strength by 30%, effectively increased the payload, and saved about $75 million in costs. McDonnell Douglas uses 2090-T81 plates to make a 2.44m diameter and 3.05m long cryogenic chamber for the delta wing rocket to hold fuel and liquid oxygen containers, reducing mass by 15%. The three components of the American General Dynamics Space Company on the Atlas and Centaur launch vehicles are made of 2090 alloy, with a total of 70kg, and the mass is 8% lighter than in 2024. In December 1997, the outer storage tank of the US space shuttle "Endeavours" was replaced by 2195 instead of 2219, and the carrying capacity was increased by 3.4t.

Al-Li alloy also has many applications in Russia's aerospace industry. Russia has developed 1460 alloy by adding 0.20% Sc element on the basis of 1450 alloy, which has better performance and is applied to the structural parts of the large launch vehicle "Energy". It is also used in other rockets, the Space Shuttle Blizzard and the structural parts of the space station.