Materials 269

Aluminum Alloys

Aluminum alloys do not possess the high strength and temperature capability of iron-, nickel- or cobalt-based al- loys. They are very useful where low density and moder- ate strength capability are required. Because of their rela- tively low melting point (less than 660°C), they can be readily worked by a number of different processes that met- als with higher melting points cannot. Aluminum alloys are designated by their major alloying consituent. The common classes of alloying additions are listed in Table 11. Since alloy additions affect the melting range and strengthening mechanisms, a number of classes of alloys are generated that can have varying responses to heat treatment. Some al- loys are solution heat treated and naturally aged (at room temperature), while some are solution treated and dficially aged (at elevated temperature). Table 12 lists several pos- sible treatments for wrought aluminum alloys, and Table 13 lists typical applications.

Table 12 Common Al Alloy Temper Designations

0 F

T1

T2

T3

T4

T5

T6 T7 T8 T9

T10

Annealed. As fabricated. Cooled from an elevated temperature shaping process and

Cooled from an elevated temperature shaping process, cold naturally aged to a substantially stable condition.

worked, and naturally aged to a substantially stable condition.

substantially stable condition.

stable condition.

artifically aged.

Solution heat treated, cold wotked, and naturally aged to a

Solution heat treated and naturally aged to a substantially

Cooled from an elevated temperature shaping process and

Solution treated and artificially aged. Solution treated and stabilized. Solution treated, cold worked, and artificially aged. Solution treated, cold worked, and artificially aged. Cooled from an elevated temperature shaping process, cold

worked, and artificially ased. - - From ASM Metals Handbook, Vo/. 2,m Ed. p2J

Table 13 Typical Applications and Mechanical Properties of

Aluminum Alloys Table 11

Major Alloying Elements for Aluminum Alloys and Compositions for Some Commonly Used Alloys

1050 1100 201 4

2024 4032 4043 5052 6063 7075

Chemical equipment, railroad tank cars Sheet metal work, spun hollow ware, fin stock Heavy duty forgings, plates and extrusions for aircraft fittings,

Truck wheels, screw machine products, aircraft s t t ~ c t ~ r e ~ Pistons Welding electrode Sheet metal work, hydraulic tube, appliances Pipe railing, furniture, architectural extrusions Aircraft and other structures

wheels, truck frames Alloying element series

lXXX 2xxx 3xxx 4xxx 5xxx 6xxx 7xxx 8xxx 9XXX

~

None 99.00% or greater AI Copper Manganese Silicon Magnesium Magnesium and silicon Zinc Other element Unused series

Tensile Yield Elongation Hardness Strength Srength in50mm HB

Alloy Temper mi) &Si) ( O h ) (500 @/lo mm ball)

1050 1100 2014

0 11 0 13 0 27 T6 70 0 27 T3 70 T6 55 0 21 0 28 0 13 T1 22 T6 35 0 38 T6 83

- 23 45

135 47

1 20 1 20

36 25 42 73 60

150

-

zn cu

- 0.1 2 4.4 4.4 0.9

Mg

- - 0.5 1.5 1 .o

AI

99.50 99.00 93.5 93.5 85.0 94.8 97.2 98.9 90.0

Si

- - 0.8

12.2 5.2

0.4

-

- -

Mn

- - 0.8 0.6

AA

1050 1100 201 4 2024 4032 4043 5052 6063 7075

2024

4032 4043 5052 6063

- 0.9Ni - -

0.25

0.23 - 2.5

0.7 2.5

- - 1.6

7075 - 5.6

Adapted from ASM Metals Handbook, vd. 2,W Ed. p]. Adapted from ASM Metals Handbook, VOL 2,9th Ed. p2].