Aerospace Aluminum Alloys

6061, 7075, 2024 Chemical Composition

Chemical Composition Limits for Aluminum AlloysComposition in percent by weight according to The Aluminum Association. The values associates maximum limits unless shown as a range or a minumum.

Alloy Si Fe Cu Mn Mg Cr Zn Ti Others Each

Others Total

Al. Min.

6061 0.40-0.8 0.7 0.15-

0.40 0.15 0.8-1.2

0.04-0.35 0.25 0.15 0.05 0.15 Rem.

7075 0.40 0.50 1.2-2.0 0.30 2.1-2.9

0.18-0.28

5.1-6.1 0.20 0.05 0.15 Rem.

2024 0.50 0.50 3.8-4.9 0.30-0.9

1.2-1.8 0.10 0.25 0.15 0.05 0.15 Rem.

6061, 7075, 2024 Mechanical Properties

Typical Mechanical Properties The following typical properties are not guaranteed since most cases they are averages for various sizes and methods of manufacture and may not be exactly representative of any particular product or size. The data is intended for comparing alloys and tempers and should not be used for design purposes.

Tensile Strength

Yield Strength

Elongation (%) for the following gauge

ranges:

Tensile Strength

Yield Strength

Elongation (%) for the following gauge

ranges:

Alloy Temper (ksi) (ksi) 0.010-0.050 0.051-.125 (MPa) (MPa) 0.25-1.25mm

1.26-3.0mm

6061

O 18 8 25 26 124.1 55.2 25 26

T4 35 21 22 24 241.3 144.8 22 24

T6 45 40 12 17 310.3 275.8 12 17

2024

O 27 11 18 20 186.2 75.8 18 20

T3 70 50 16 18 482.6 344.7 16 18

T4 68 47 20 19 468.8 324.1 20 19

Aluminum Specification Cross ReferenceAlloy Form ASTM AMS ASME

6061

Aluminum Coil ASTM-B209 4025, 4026, 4027AMS-QQ-A-250/11 SB-209

Aluminum Strip ASTM-B209 4025, 4026, 4027AMS-QQ-A-250/11 SB-209

Aluminum Plate ASTM-B209 4025, 4026, 4027AMS-QQ-A-250/11 SB-209

2024

Aluminum Coil ASTM-B209 4035, 4037

Aluminum Strip ASTM-B209 4035, 4037

Aluminum Plate ASTM-B2094035, 4037

Other general differences

Characteristics 2024 6061Weldability Poor GoodMachining Average GoodCorrosion Resistance

Poor Very Good

2024-T3 Aluminum

Minimum Properties

Ultimate Tensile Strength, psi

70,000

Yield Strength, psi 50,000

Brinell Hardness 120

Rockwell Hardness B75

Chemistry Aluminum (Al) 90.7 - 94.7%

Chromium (Cr) 0.1% max

Copper (Cu) 3.8 - 4.9%

6061-T6 Aluminum

Physical and Mechanical Properties

Ultimate Tensile Strength, psi

45,000

Yield Strength, psi 40,000

Brinell Hardness 95

Rockwell Hardness B60

Chemistry Aluminum (Al) 95.8 - 98.6%

Chromium (Cr) 0.04 - 0.35%

Copper (Cu) 0.15 - 0.40%

Iron (Fe) 0.5% max

Magnesium (Mg) 1.2 - 1.8%

Manganese (Mn) 0.3 - 0.9%

Silicon (Si) 0.5% max

Iron (Fe) 0.70%

Magnesium (Mg) 0.8 - 1.2%

Manganese (Mn) 0.15% max

Silicon (Si) 0.4 - 0.8%

Zinc (Zn) Zinc (Zn) 0.25%

6061 This is the least expensive and most versatile of the heat-treatable aluminum alloys. It has most of the good qualities of aluminum. It offers a range of good mechanical properties and good corrosion resistance. It can be fabricated by most of the commonly used techniques. In the annealed condition it has good workability. In the T4 condition fairly severe forming operations may be accomplished. The full T6 properties may be obtained by artificial aging. It is welded by all methods and can be furnace brazed. It is available in the clad form (“Alclad”) with a thin surface layer of high purity aluminum to improve both appearance and corrosion resistance. Applications: This grade is used for a wide variety of products and applications from truck bodies and frames to screw machine parts and structural components. 6061 is used where appearance and better corrosion resistance with good strength are required.

2024 This is one of the best known of the high strength aluminum alloys. With its high strength and excellent fatigue resistance, it is used to advantage on structures and parts where good strength-to-weight ratio is desired. It is readily machined to a high finish. It is readily formed in the annealed condition and may be subsequently heat treated. Arc or gas welding is generally not recommended, although this alloy may be spot, seam or flash welded. Since corrosion resistance is relatively low, 2024 is commonly used with an anodized finish or in clad form (“Alclad”) with a thin surface layer of high purity aluminum. Applications: aircraft structural components, aircraft fittings, hardware, truck wheels and parts for the transportation industry.