2024 Aluminum Alloy Sheet and Plate
Alloy 2024 was introduced by Alcoa in 1931 as an alclad sheet in the T3 temper. It was the first Al-Cu-Mg alloy to have a yield strength approaching 50,000-psi and generally replaced 2017-T4 (Duralumin) as the predominant 2XXX series aircraft alloy. With its relatively good fatigue resistance, especially in thick plate forms, aluminum alloy 2024 continues to be specified for many aerospace structural applications. 2024 varient alloys, such as higher purity 2124 and 2324, with improvements in strength and other specific characteristics, have also found application in critical aircraft structures. An improved sheet alloy for fuselage applications was introduced in 1991. Alclad C188 offers
improved fracture toughness and fatigue crack growth while maintaining the strength characteristics of 2024.
Aluminum Alloy 2024 is available in bare and alclad sheet and plate product forms in the annealed state and several tempers of T3, T4, and T8 types.
Alloy 2024 plate products are used in fuselage structurals, wing tension members, shear webs and ribs and structural areas where stiffness, fatigue performance and good strength are required. Sheet products, usually alclad, are used extensively in commercial and military aircraft for fuselage skins, wing skins and engine areas where elevated temperatures to 250°F (121°C) are often encountered.
CHEMICAL COMPOSITION LIMITS (WT.%)
Si . . . 0.50
Fe. . . 0.50
Cu . . 3.8-4.9
Mn . . 0.30-0.9
Mg . . 1.2-1.8
Cr. . . 0.10
Zn . . 0.25
Ti . . . 0.15
Others, each . . 0.05
Others, total . . 0.15