Aluminium-lithium alloy

Aluminum -lithium alloys are aluminum alloys by the addition of lithium have improved properties. In particular the specific weight of the alloy can be reduced so as decreases the density of the alloy is 3% with each inserted mass percent lithium. In addition, increases the modulus of elasticity.

Besides these lithium alloys are generally added other elements, such as copper, manganese, magnesium, silver, zirconium, and scandium. In particular, the copper content may be substantially higher than the lithium content ( 2XXXer alloys).

Aluminum-lithium alloys in aircraft, spacecraft and missiles, but also in the vehicle for use. For example, the external tank of the space shuttle as well as parts of the passenger aircraft Boeing B777, the new Airbus A350 and the Airbus A380 from these alloys are manufactured.

The first generation of aluminum -lithium alloys - approximately between 1950 and 1990 - was of high susceptibility to corrosion, low ductility ( Gleitbandbildung by δ' precipitates ) affected and low temperature resistance. These problems were encountered in the second generation alloys with a reduced lithium content.

In the current third generation, apart from the mechanical properties of toughness and stress behavior at high loads become critical. However, there must be due to the high oxidation potential of lithium special protections in the foundry.

Examples of aluminum-lithium alloys,

• 2091 AA: 2.1% Cu 2.0% Li 0.10% Zr residual aluminum ( 1st generation)
• 8090 AA: 2.45% Li 0.12% Zr 1.3% Cu 0.95 Mg residual aluminum ( 1st generation)

Swell

• Alloy