Materiales Aeroespaciales

In 1903 was a one-piece casting in an aluminum alloy containing 8% copper; aluminum propeller blades appeared as early as 1907; and aluminum covers, seats, cowlings, cast brackets, and similar parts were common by the beginning of the First World War.
Alloys for Airframe Components

Alloy 7075-T6 (70,000-psi yield strength), an Al-Zn-Mg-Cu alloy, was introduced in 1943. Since then, mostaircraft structures have been specified in alloys of this type. The first aircraft designed in 7075-T6 was the Navy’s P2V patrol bomber. A higher-strength alloy in the same series, 7178-T6 (78,000-psi yield strength), was developed in 1951; it has not generally displaced 7075-T6, which has superior fracture toughness. Alloy 7178-T6 is used primarily in structural members where performance is criticalunder compressive loading.
Alloy 7079-T6 was introduced in the United States in 1954. In forged sections over 3 in. thick, it provides higher strength and greater transverse ductility than 7075-T6. It now is available in sheet, plate, extrusions, and forgings.
Alloy X7080-T7, with higher resistance to stress corrosion than 7079-T6, is being developed for thick parts. Because it is relativelyinsensitive to quenching rate, good strengths with low quenching stresses can be produced in thick sections.

Aluminum alloy castings traditionally have been used in nonstructural airplane hardware, such as pulley brackets, quadrants, doublers, clips, ducts, and wave guides. They also have been employed extensively in complex valve bodies of hydraulic control systems. The philosophy of someaircraft manufacturers still is to specify castings only in places where failure of the part cannot cause loss of the airplane. 
Fusion welded aluminum primary structures in airplanes are virtually nonexistent, because the high-strength alloys utilized have low weldability and low weld-joint efficiencies. Some of the alloys, such as 2024-T4, also have their corrosion resistance lowered in theheat-affected zone if left in the as-welded condition.
Adhesive bonding is a common method of joining in both primary and secondary structures. Its selection is dependent on the design philosophy of the aircraft manufacturer. It has proven satisfactory in attaching stiffeners, such as hat sections to sheet, and face sheets to honeycomb cores. Also, adhesive bonding has withstood adverse exposures suchas sea-water immersion and atmospheres

Light Aircraft

Light aircraft have airframes primarily of all-aluminum semi-monocoque construction, however, a few light planes have tubular truss load-carrying construction with fabric or aluminum skin, or both.

Skin sheet on light airplanes of recent design and construction generally is alclad 2024-T3. The internal structure comprises stringers,spars, bulkheads, chord members, and various attaching fittings made of aluminum extrusions, formed sheet, forgings, and castings.
The alloys most used for extruded members are 2024-T4 for sections less than 0.125 in. thick and for general application, and 2014-T6 for thicker, more highly stressed sections. Alloy 6061-T6 has considerable application for extrusions requiring thin sections andexcellent corrosion resistance. Alloy 2014-T6 is the primary forging alloy, especially for landing gear and hydraulic cylinders. Alloy 6061-T6 and its forging counterpart 6151-T6 often are utilized in miscellaneous fittings for reasons of economy and increased corrosion performance, when the parts are not highly stressed.

Alloys 356-T6 and A356-T6 are the primary casting alloys employed forbrackets, bellcranks, pulleys, and various fittings. Wheels are produced in these alloys as permanent mold or sand castings. Die castings in alloy A380 also are satisfactory for wheels for light aircraft.
For low-stressed structure in light aircraft, alloys 3003-H12, H14, and H16; 5052-O, H32, H34, and H36; and 6061-T4 and T6 are sometimes employed. These alloys are also primary selections for fuel,...