Aluminium in Aircraft manufacturing

Wide application of aluminium in industry is mainly explained by its large natural resources as well as a set of chemical, physical and mechanical properties.

Aluminium is one of the most widespread metals, regarding its content in the earth's crust (~8 %).

Among one of aluminium's advantages shall be considered its low density (2.7 g/cm3), relatively high strength properties, good thermal and electric conductivity, technological effectiveness, high corrosion resistance. Due to combination of these properties aluminium is considered to be one of the most important engineering materials.

Aluminium alloys are the main structural material in aircraft industry at the present-day stage of subsonic and supersonic aircraft development. Alloys of 2ххх, Зххх, 5ххх, 6ххх and 7ххх series are widely used for aircraft industry in the USA. 2ххх series is recommended for work at high operating temperatures and with increased values of fracture toughness ratio. Alloys of 7ххх series are recommended for operation of significantly loaded parts at lower temperatures and for parts with high corrosion resistance under stress. Alloys of Зххх, 5ххх and 6xxx series are used for low-loaded assemblies They are also used in hydraulic, oil and fuel systems.

Al-Zn-Mg-Cu high-strength aluminium alloys hardened by heat treatment and Al-Mg-Cu average- and high-strength aluminium alloys are successfully used for aircraft equipment production in Russia. They are structural material for skin and inner set of airframe components (body, wing, keel, etc.).

1420 alloy pertaining to Al-Zn-Mg system is used for airliner welded body design. Usage of aluminium-magnesium corrosion-resistant welded alloys (AМг5, АМг6) and Al-Zn-Mg alloys (1915, В92, 1420) is provided for hydroplane production.

Aluminium welded alloys have undeniable advantage when designing space technology items. High strength-to-weight ratio, stiffness-to-weight ratio of the material provided for manufacture of missile tanks, intertank and nose parts with high directional stability. Among the advantages of aluminium alloys (2219 and others) is their operationability under cryogenic temperatures in contact with liquid oxygen, hydrogen and helium. These alloys are capable of the so-called cryogenic hardening, i.e. strength and ductility increase simultaneously with the decrease of temperature.

1460 alloy pertains to Al-Cu-Li system and is most promising for design and manufacture of tank structures with regard to cryogenic type of fuel - compressed oxygen, hydrogen or natural gas.