2024 aluminium alloy is an

aluminium alloy An aluminium alloy (or aluminum alloy; see spelling differences) is an alloy in which aluminium (Al) is the predominant metal. The typical alloying elements are copper, magnesium, manganese, silicon, tin, nickel and zinc. There are two pr ...

, with

copper Copper is a chemical element with the symbol Cu (from la, cuprum) and atomic number 29. It is a soft, malleable, and ductile metal with very high thermal and electrical conductivity. A freshly exposed surface of pure copper has a pink ...

as the primary alloying element. It is used in applications requiring high strength to weight ratio, as well as good

fatigue Fatigue describes a state of tiredness that does not resolve with rest or sleep. In general usage, fatigue is synonymous with extreme tiredness or exhaustion that normally follows prolonged physical or mental activity. When it does not resolve ...

resistance. It is

weldable The weldability, also known as joinability,. of a material refers to its ability to be welded. Many metals and thermoplastics can be welded, but some are easier to weld than others (see Rheological weldability). A material's weldability is used to ...

only through

friction welding Friction welding (FRW) is a solid-state welding process that generates heat through mechanical friction between workpieces in relative motion to one another, with the addition of a lateral force called "upset" to plastically displace and fuse the m ...

, and has average

machinability Machinability is the ease with which a metal can be cut (machined) permitting the removal of the material with a satisfactory finish at low cost.Degarmo, p. 542. Materials with good machinability (free machining materials) require little power to c ...

. Due to poor

corrosion Corrosion is a natural process that converts a refined metal into a more chemically stable oxide. It is the gradual deterioration of materials (usually a metal) by chemical or electrochemical reaction with their environment. Corrosion engi ...

resistance, it is often clad with

aluminium Aluminium (aluminum in American and Canadian English) is a chemical element with the symbol Al and atomic number 13. Aluminium has a density lower than those of other common metals, at approximately one third that of steel. It ha ...

or Al-1Zn for protection, although this may reduce the fatigue strength. In older systems of terminology, 2XXX series alloys were known as

duralumin Duralumin (also called duraluminum, duraluminium, duralum, dural(l)ium, or dural) is a trade name for one of the earliest types of age hardening, age-hardenable aluminium alloys. The term is a combination of ''Dürener'' and ''aluminium''. Its ...

, and this alloy was named 24ST. 2024 is commonly extruded, and also available in

alclad Alclad is a corrosion-resistant aluminium sheet formed from high-purity aluminium surface layers metallurgically bonded (rolled onto) to high-strength aluminium alloy core material. It has a melting point of about 500 degrees celsius, or 932 degree ...

sheet and plate forms. It is not commonly forged (the related

2014 aluminium alloy 2014 aluminium alloy (aluminum) is an aluminium-based alloy often used in the aerospace industry. It is easily machined in certain tempers, and among the strongest available aluminium alloys, as well as having high hardness. However, it is difficu ...

is, though).

Basic properties

Aluminium alloy 2024 has a

density Density (volumetric mass density or specific mass) is the substance's mass per unit of volume. The symbol most often used for density is ''ρ'' (the lower case Greek letter rho), although the Latin letter ''D'' can also be used. Mathematicall ...

of 2.78 g/cm³ (0.1 lb/in³),

electrical conductivity Electrical resistivity (also called specific electrical resistance or volume resistivity) is a fundamental property of a material that measures how strongly it resists electric current. A low resistivity indicates a material that readily allows ...

of 30% IACS,

Young's Modulus Young's modulus E, the Young modulus, or the modulus of elasticity in tension or compression (i.e., negative tension), is a mechanical property that measures the tensile or compressive stiffness of a solid material when the force is applied ...

of 73 GPa (10.6 Msi) across all tempers, and begins to melt at . 2024 aluminium alloy's composition roughly includes 4.3–4.5%

, 0.5–0.6%

manganese Manganese is a chemical element with the Symbol (chemistry), symbol Mn and atomic number 25. It is a hard, brittle, silvery metal, often found in minerals in combination with iron. Manganese is a transition metal with a multifaceted array of ...

, 1.3–1.5%

magnesium Magnesium is a chemical element with the symbol Mg and atomic number 12. It is a shiny gray metal having a low density, low melting point and high chemical reactivity. Like the other alkaline earth metals (group 2 of the periodic ...

and less than a half a percent of silicon, zinc, nickel, chromium, lead and bismuth.

Chemical composition

The alloy composition of 2024 is:ASM Aerospace Specifications Metals Inc.
retrieved 18 September 2019. *

Silicon Silicon is a chemical element with the symbol Si and atomic number 14. It is a hard, brittle crystalline solid with a blue-grey metallic luster, and is a tetravalent metalloid and semiconductor. It is a member of group 14 in the periodic ...

no minimum, maximum 0.5% by weight *

Iron Iron () is a chemical element with symbol Fe (from la, ferrum) and atomic number 26. It is a metal that belongs to the first transition series and group 8 of the periodic table. It is, by mass, the most common element on Earth, right in ...

no minimum, maximum 0.5% *

Copper Copper is a chemical element with the symbol Cu (from la, cuprum) and atomic number 29. It is a soft, malleable, and ductile metal with very high thermal and electrical conductivity. A freshly exposed surface of pure copper has a pink ...

minimum 3.8%, maximum 4.9% *

Manganese Manganese is a chemical element with the Symbol (chemistry), symbol Mn and atomic number 25. It is a hard, brittle, silvery metal, often found in minerals in combination with iron. Manganese is a transition metal with a multifaceted array of ...

minimum 0.3%, maximum 0.9% *

Magnesium Magnesium is a chemical element with the symbol Mg and atomic number 12. It is a shiny gray metal having a low density, low melting point and high chemical reactivity. Like the other alkaline earth metals (group 2 of the periodic ...

minimum 1.2%, maximum 1.8% *

Chromium Chromium is a chemical element with the symbol Cr and atomic number 24. It is the first element in group 6. It is a steely-grey, lustrous, hard, and brittle transition metal. Chromium metal is valued for its high corrosion resistance and hard ...

no minimum, maximum 0.1% *

Zinc Zinc is a chemical element with the symbol Zn and atomic number 30. Zinc is a slightly brittle metal at room temperature and has a shiny-greyish appearance when oxidation is removed. It is the first element in group 12 (IIB) of the periodi ...

no minimum, maximum 0.25% *

Titanium Titanium is a chemical element with the symbol Ti and atomic number 22. Found in nature only as an oxide, it can be reduced to produce a lustrous transition metal with a silver color, low density, and high strength, resistant to corrosion i ...

no minimum, maximum 0.15% * Other elements no more than 0.05% each, 0.15% total * Remainder

(90.7–94.7%)

Mechanical properties

The mechanical properties of 2024 depend greatly on the temper of the material.Alcoa 2024 data sheet
(pdf), accessed October 13, 2006

2024-O

2024-O temper aluminium has no heat treating. It has an ultimate

tensile strength Ultimate tensile strength (UTS), often shortened to tensile strength (TS), ultimate strength, or F_\text within equations, is the maximum stress that a material can withstand while being stretched or pulled before breaking. In brittle materials ...

of , and maximum

yield strength In materials science and engineering, the yield point is the point on a stress-strain curve that indicates the limit of elastic behavior and the beginning of plastic behavior. Below the yield point, a material will deform elastically and wi ...

of no more than . The material has elongation (stretch before ultimate failure) of 10–25%, this is the allowable range per applicable AMS specifications.

2024-T3

T3 temper 2024 sheet has an ultimate tensile strength of and yield strength of at least . It has an elongation of 10–15%.

2024-T4

Solution treated and naturally aged.

2024-T5

Cooled from hot working and artificially aged (at elevated temperature)

2024-T351

T351 temper 2024 plate has an ultimate tensile strength of and yield strength of . It has elongation of 20%.

Uses

Due to its high strength and fatigue resistance, 2024 is widely used in

aircraft An aircraft is a vehicle that is able to flight, fly by gaining support from the Atmosphere of Earth, air. It counters the force of gravity by using either Buoyancy, static lift or by using the Lift (force), dynamic lift of an airfoil, or in ...

, especially

wing A wing is a type of fin that produces lift while moving through air or some other fluid. Accordingly, wings have streamlined cross-sections that are subject to aerodynamic forces and act as airfoils. A wing's aerodynamic efficiency is e ...

and

fuselage The fuselage (; from the French ''fuselé'' "spindle-shaped") is an aircraft's main body section. It holds crew, passengers, or cargo. In single-engine aircraft, it will usually contain an engine as well, although in some amphibious aircraft t ...

structures under tension.Aluminum Information at aircraftspruce.com
accessed August 15, 2011 Additionally, since the material is susceptible to thermal shock, 2024 is used in qualification of liquid penetrant tests outside of normal temperature ranges.

ASME Boiler and Pressure Vessel Code (BPVC) The ASME Boiler & Pressure Vessel Code (BPVC) is an American Society of Mechanical Engineers (ASME) standard that regulates the design and construction of boilers and pressure vessels. The document is written and maintained by volunteers chosen for ...

1998 Edition, Section 5, Article 6, Subparagraph T-653.2

References

Aluminium alloy table

{{Aluminium alloys 2024