According to reports, for every 1 kg reduced, the launch cost of the spacecraft will save about 20,000 dollars. Therefore, structural weight reduction can be described as a "gramme care" in the aerospace field.
If the weight of the fighter is reduced by 15%, the taxiing distance of the aircraft can be shortened by 15%, the range can be increased by 20%, and the effective load can be increased by 30%. Therefore, countries all over the world attach great importance to the research and development of lightweight structural materials for aerospace.
Aircraft aluminum alloy is widely used in the aerospace field due to its low density, moderate strength, easy processing and forming, strong corrosion resistance, rich resources, and strong recyclability. The skins, beams, ribs, stringers, bulkheads and landing gears on the aircraft can all be made of aluminum alloy.
Depending on the purpose of the aircraft, the amount of aluminum used varies. The aluminum alloy percentage in the manufacturing materials of civil aircraft that focus on economic benefits is very high. For example, the aluminum alloy used in the Boeing 767 passenger aircraft accounts for about 81% of the weight of the body structure.
At present, aluminum alloy materials used in aviation and civil aircraft mainly include: aluminum alloy castings, aluminum alloy forgings, large-section aluminum alloy extruded profiles, aluminum alloy thick plates, and aluminum-lithium alloys.
Aviation aluminum alloys are mainly deformable aluminum alloys that can be heat treated, such as 2000 and 7000 series aluminum alloys. Aluminum alloy 2024 is used for aircraft structural parts. 2048 aviation aluminum alloy is mainly used to manufacture aerospace vehicle structural parts and weapon structural parts.
2218 is mainly used in aircraft engines and diesel engine pistons, aircraft engine cylinder heads, jet engine impellers and compressor rings. 2219 is used for welding oxidizer tanks of space rockets, supersonic aircraft skins and structural parts.
7049 is used for aircraft and missile parts, such as landing gear hydraulic cylinders and extrusions. 7050 aviation aluminum alloy is used for medium and thick plates, extrusions, free forgings and die forgings of aircraft structural parts. 7178 aviation aluminum alloy is used to manufacture parts and components that require high compressive yield strength for aerospace vehicles.
7475 aluminum sheet is used for fuselage panels, wing skeletons, stringers, etc. 7A04 is used for aircraft skins, screws, and force-bearing components such as girder stringers, bulkheads, wing ribs, and landing gear. 7075 aluminum plate is used for the upper outer panel of the wing, stringer, wing rib, empennage,etc.