Aluminum has played a vital role in the aerospace industry since the beginning of manned flight. Today, aluminum makes up 75-80% of a modern aircraft. Its strength, lightweight, and corrosion resistance make it the ideal material for building aircraft.
In fact, even before the Wright Brothers first successful flight in 1903, Count Ferdinand Zeppelin used aluminum to make the frames of his airship that flew for the first time in 1900. And a few years later, the Wright Brothers built a lightweight aircraft engine using a cylinder block and other parts made with aluminum.
Aluminum parts are made from a variety of alloys grades of material and different methods of production. These different alloys and grades are used for particular aerospace applications. The most common alloy used is 2024, which is typically used for cowls, aircraft skins, and common aircraft structures, as well as for repair and restoration. Another high-strength alloy used in the aviation industry is 7075, which is used to strengthen aircraft structures. 5052 is an aluminum grade often used for fuel tanks because of its excellent moisture and corrosion resistance, and 3003 grade aluminum sheet is commonly used for cowls and baffle plating.
Two of the most common forms used in the aerospace industry are aluminum sheets and plates. Aluminum sheets and plates start with ingots of raw aluminum which are preheated before processing. Once the ingots are properly heated, the aluminum is fed into a breakdown mill and then formed into a thick sheet. From here, the sheet is rolled repeatedly until it is reduced to a thickness of just a few inches. After the rolling process, the rolled aluminum sheet is wound into a coil and cooled by passing them through several cold rolling mills. The cold rolling of the aluminum sheet is the final step of the process.
Aluminum sheet is used in manufacturing various types of containers for the packaging industry. It is also commonly used in tractor-trailers and automobile body panels, for cookware and appliances, as well as building products for siding, awnings, roofing, gutters, and carports. Aluminum plate is the most often used in the aerospace, transportation, and military industries for heavy-duty applications.
The use of gauge number to designate metal thickness is no longer in use due to the development of more accurate measurement technology. Today, the common practice is to specify the exact thickness of the metal, though the gauge may also be listed. The standard thicknesses (and gauge) for aluminum sheet and plate are found in the Standard Specification for Aluminum and Aluminum-Alloy Sheet and Plate: ASTM B209-14.
In conclusion, the importance of aluminum in the aerospace industry cannot be overstated. Its strength, lightweight, and corrosion resistance make it the ideal material for building aircraft and has been used since the beginning of manned flight. Different grades and alloys are used for specific aerospace applications. Aluminum sheet and plate are widely used and in demand due to the versatility of aluminum alloys. The use of gauge number to designate metal thickness is no longer in use due to the development of more accurate measurement technology.