What is Aluminum?
Aluminum is widely acknowledged as one of the most versatile materials available today. Due mainly to a unique combination of characteristics, there is an aluminum alloy to fit almost any application imaginable.
One of aluminum’s most appealing properties is a high resistance to corrosion due to the natural oxide film that forms when it is exposed to air. Some aluminum alloys are stronger than structural steel, yet all the alloys are light in weight.
Aluminum is nontoxic, which allows it to have direct contact with food products without harmful effects on the body. Because of this characteristic, it is widely used to make cooking utensils, and is very prevalent in equipment for food processing industries
Aluminum is one of two common metals having an electrical conductivity high enough for use as electrical conductors. High thermal conductivity is another feature that promotes widespread use in cooking utensils and heat exchangers. Another very important asset of aluminum is the ease with which it can be fabricated, machined, and joined by almost any method.
Aluminum Wrought Alloys
Non-Heat Treatable Alloys
The initial strength of the non-heat treatable group of alloys depends upon the hardening effects of elements such as manganese, magnesium, silicon, and iron, used singly or in combination. These alloys can be further strengthened only by cold working. Typical uses and characteristics of these alloys are summarized in the following table:
Aluminum Alloy | Aluminum Characteristics | Aluminum Uses |
---|---|---|
1100 | Excellent corrosion resistance, high thermal and electrical conductivity, excellent workability, readily welded and brazed |
Chemical equipment, spun hollow ware, decorative parts and trim, sheet metal work, cooking utensils, heat exchanger fins |
1350 | Developed especially for electrical conductor use | Electrical conductors, coil windings, power transmission systems |
3003 | General purpose, moderate strength, good workability and weldability, high resistance to corrosion |
Cooking utensils, refrigerator panels, chemical equipment, general sheet metal work, eyelet stock, gasoline tanks, heat exchangers, storage tanks |
5005 | Moderate to high strength, good welding properties, good corrosion resistance, forms easily, excellent for anodizing since it exhibits less tendency to structural streaking |
Appliances, insulation jacketing, cooking utensils, chemical equipment, small boats |
5052 | Excellent resistance to salt water corrosion, good weldability and workability, higher strength than 1100 or 3003 alloys, good finishing characteristics |
Home appliances, chemical drums, truck and bus bodies, small boats, sheet metal parts, kitchen cabinets, fencing, fan blades, tank cars and trailers |
5086 | Good forming properties, excellent corrosion resistance in marine environments, excellent weldability, stronger than 5052 |
Shipyard plate, tanks, unfired welded pressure vessels, auto aircraft cryogenics, drilling rigs |
Temper Designations for the Non-Heat Treatable Alloys
Temper designations for non-heat treatable alloys are indicated by suffixes to the alloy number as follows:
F As fabricated
O Annealed
H Strain hardened
The letter “H” is always followed by 2 or 3 digits. The first digit indicates the particular method used to obtain the temper, as follows:
H1 Strain hardened only
H2 Strain hardened, then partially annealed
H2 Strain hardened, then stabilized
The temper is indicated by the second digit. For instance:
HX2 1/4 hard
HX4 1/2 hard
HX6 3/4 hard
HX8 full hard
HX9 extra hard
The third digit, when used, indicates a variation of a two-digit temper. It is used when the degree of control of temper or the mechanical properties or both differ from, but are close to, that (or those) for the two-digit H temper designation to which it is added, or when some other characteristic is significantly affected. NOTE: The minimum ultimate tensile strength of a three-digit H temper must be at least as close to that of the corresponding two-digit H temper as it is to the adjacent two-digit H tempers. Products in the H temper whose mechanical properties are below H_1 shall be variations of H_1.
Heat Treatable Alloys
The initial strength of the heat treatable group of alloys is heightened by the addition of elements such as copper, zinc, silicon, and magnesium, used singly or in combination. These alloys may be further strengthened by a suitable thermal treatment. Typical uses and characteristics of these alloys are summarized in the following table:
Aluminum Alloy | Aluminum Characteristics | Aluminum Uses |
---|---|---|
2011 Aluminum | Good machinability, good mechanical properties, excellent free- cutting properties |
Screw machine products, tube fittings, pipe stems, atomizer and hose parts |
2017 Aluminum | Stronger than 2011, fair workability and corrosion resistance, good machinability |
Screw machine products, rivets, fasteners, aircraft components |
2024 Aluminum | High strength, formability and workability is fair, may be spot welded |
Aircraft parts, truck wheels, scientific instruments, veterinary and orthopedic braces and equipment |
2024 ALCLAD Aluminum | Cladding provides superior corrosion resistance, good appearance | Aircraft frames and skins, washers, truck bodies, railroad car roofs and sides |
6013 Aluminum | This alloy features B-rated machinability along with improved tensile properties |
Applications that require improved machinability over 6061 alloys |
6020 Aluminum | A lead free alloy with A-rated machinability. High mechanical properties, excellent anodizing response, excellent corrosion resistance, good brazability and weldability |
Screw machine parts |
6061 Aluminum | One of the most versatile of heat-treatable alloys, good formability and high resistance to corrosion, medium strength relative to 2000 or 7000 alloys |
Truck and bus bodies, sailboats, canoes, transmission towers, chemical equipment, paper and textile rolls |
6063 Aluminum | High corrosion resistance, medium strength, good natural finish | Irrigation pipe, store fronts, architectural trim, pipe railing, furniture |
6101 Aluminum | Excellent electrical and thermal conductivity, used for electrical conductors |
High strength bus conductors |
6262 Aluminum | Excellent machinability, good resistance to corrosion, readily welded, good finishing characteristics |
Screw machine products, camera parts, fittings, nuts, couplings |
7050 Aluminum | This alloy retains its strength in thicker sections while maintaining good corrosion resistance and toughness |
Aircraft applications including fuselage frames and bulkheads |
7075 Aluminum | One of the strongest and hardest alloys available, good machin- ability, fair corrosion resistance, excellent finishing characteristics |
Aircraft, ordnance, keys, small gears |
7075 ALCLAD Aluminum | Provides strength of 7075 with superior corrosion resistance from cladding |
Aerospace applications requiring maximum corrosion resistance, skis |
Temper Designations for the Heat Treatable Alloys
These alloys can be heat treated to produce stable tempers other than F, O, or H and are designated as follows:
T3 Solution heat treated, then cold worked
T351 Solution heat treated, naturally aged, stretcher stress relieved
T4 Solution heat treated and naturally aged to a substantially stable condition
T6 Solution heat treated, then artificially aged
T42 Solution heat treated from the O or F temper to demonstrate response to heat treatment, and naturally aged to a substantially stable condition
T62 Solution heat treated from the O or F temper to demonstrate response to heat treatment, and artificially aged
T651, T751 Stress relieved by stretching
T9 Solution heat treated, artificially aged, and then cold worked
Aluminum Chemical Compositions
This table contains the chemical composition limits of wrought aluminum alloys in percent by weight maximum unless shown as a range or minimum. Except for “aluminum” and “others, ” analysis normally is made for elements for which specific limits are shown. For purposes of determining conformance to these limits, an observed value or a calculated value obtained from analysis is rounded off to the nearest unit in the last right-hand place of figures used in expressing the specified limit, in accordance with ASTM Recommended Practice E29.
Aluminum Alloy |
Silicon |
Iron |
Copper |
Manganese |
Magnesium |
Chromium |
Zinc |
Titanium |
Others(1) |
Aluminum |
||
---|---|---|---|---|---|---|---|---|---|---|---|---|
Each(2) |
Total(3) |
|||||||||||
Min.(4) |
||||||||||||
1100 Aluminum |
0.95 Si + Fe |
– |
0.05 |
– 0.20 |
0.05 |
– |
– |
0.10 |
– |
0.05(5) |
0.15 |
99.00 |
2011 Aluminum |
0.40 |
0.7 |
5.0 |
– 6.0 |
– |
– |
– |
0.30 |
– |
0.05(6) |
0.15 |
Remainder |
2014 Aluminum |
0.50 – 1.2 |
0.7 |
3.9 |
– 5.0 |
0.40 – 1.2 |
0.20 – 0.8 |
0.10 |
0.25 |
0.15 |
0.05 |
0.15 |
Remainder |
2017 Aluminum |
0.20 – 0.8 |
0.7 |
3.5 |
– 4.5 |
0.40 – 1.0 |
0.40 – 0.8 |
0.10 |
0.25 |
0.15 |
0.05 |
0.15 |
Remainder |
2024 Aluminum |
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 |
Remainder |
3003 Aluminum |
0.6 |
0.7 |
0.05 |
– 0.20 |
1.0 – 1.5 |
– |
– |
0.10 |
– |
0.05 |
0.15 |
Remainder |
5005 Aluminum |
0.30 |
0.7 |
0.20 |
0.20 |
0.50 – 1.1 |
0.10 |
0.25 |
– |
0.05 |
0.15 |
Remainder |
|
5052 Aluminum |
0.25 |
0.40 |
0.10 |
0.10 |
2.2 – 2.8 |
0.15 – 0.35 |
0.10 |
– |
0.05 |
0.15 |
Remainder |
|
5083 Aluminum |
0.40 |
0.40 |
.10 |
0.4 – 1.0 |
4.0 – 4.9 |
0.05 –0.25 |
0.25 |
0.15 |
0.05 |
0.15 |
Remainder |
|
5086 Aluminum |
0.40 |
0.50 |
0.10 |
0.20 – 0.7 |
3.5 – 4.5 |
0.05 – 0.25 |
.025 |
0.15 |
0.05 |
0.15 |
Remainder |
|
6013 Aluminum |
0.6 – 1.0 |
0.50 |
0.6 |
– 1.1 |
0.20 – 0.80 |
0.8 – 1.2 |
0.10 |
0.25 |
0.10 |
0.05 |
0.15 |
Remainder |
6020 Aluminum |
0.4 – 0.9 |
0.50 |
0.3 |
– 0.9 |
0.35 |
0.6 – 1.2 |
0.15 |
.20 |
0.15 |
0.05 |
0.15 |
Remainder |
6061 Aluminum |
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 |
Remainder |
6063 Aluminum |
0.20 – 0.6 |
0.35 |
0.10 |
0.10 |
0.45 – 0.9 |
0.10 |
0.10 |
0.10 |
0.05 |
0.15 |
Remainder |
|
6101(8) Aluminum |
0.30 – 0.7 |
0.50 |
0.10 |
0.03 |
0.35 – 0.8 |
0.03 |
0.10 |
– |
0.03(9) |
0.10 |
Remainder |
|
6262 Aluminum |
0.40 – 0.8 |
0.7 |
0.15 |
– 0.40 |
0.15 |
0.8 – 1.2 |
0.04 – 0.14 |
0.25 |
0.15 |
0.05(10) |
0.15 |
Remainder |
7050 Aluminum |
0.12 |
0.15 |
2.0 |
– 2.6 |
0.10 |
1.9 – 2.6 |
0.04 |
5.7 – 6.7 |
0.06 |
0.05(12) |
0.15 |
Remainder |
7075 Aluminum |
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 |
Remainder |
Notes:
(1)Includes listed elements for which no specific limit is shown.
(2)A .0008 weight percent maximum beryllium is applicable to any alloy to be used as welding electrode or welding rod.
(3)The sum of those “others” metallic elements 0.010 percent or more each, expressed to the second decimal before determining the sum.
(4)The aluminum content for unalloyed aluminum not made by a refining process is the difference between 100.00 percent and the sum of all other metallic elements present in amounts of 0.010 percent or more each, expressed to the second decimal before determining the sum.
(5)Beryllium 0.0008 maximum for welding electrode and welding rod only.
(6)Also contains 0.20 to 0.6 percent each of lead and bismuth.
(7)Gallium 0.03 percent maximum; vanadium 0.05 percent maximum.
(8)Bus conductor.
(9)Boron 0.06 percent maximum.
(10)Also contains 0.40 to 0.7 percent each of lead and bismuth.
(11)Also contains 0.10 to 0.16 percent of zirconium.
(12)Also contains 0.08 to 0.15 percent of zirconium.
Aluminum Typical Physical Properties
The following typical properties are not guaranteed since in most cases they are averages for various sizes, product forms, and methods of manufacture and may not be exactly representative of any particular product or size. These data are intended only as a basis for comparing alloys and tempers and should not be specified as engineering requirements or used for design purposes.
Aluminum Alloy | Density Lb/In3 | Average (1) Coefficient of Thermal Expansion 68 to 212°F x 10-6 per °F | Melting Range (2, 3) Approximate °F | Temper | Thermal Conductivity at 77°F Btu/Ft/Ft2/Hr/°F | Electrical Conductivity at 68°F Percent of International Annealed Copper Standard | Electrical Resistivity at 68°F Ohms-Cir Mil/Ft | |
---|---|---|---|---|---|---|---|---|
Equal Volume | Equal Weight | |||||||
Non-Heat Treatable | ||||||||
1100 Aluminum |
.098 |
13.1 |
1190 – 1215 |
0 |
128 |
59 |
194 |
18 |
|
|
|
|
H18 |
125 |
57 |
187 |
18 |
3003 Aluminum |
.099 |
12.9 |
1190 – 1210 |
0 |
112 |
50 |
163 |
21 |
|
|
|
|
H12 |
94 |
42 |
137 |
25 |
|
|
|
|
H14 |
92 |
41 |
134 |
25 |
|
|
|
|
H18 |
89 |
40 |
130 |
26 |
5005 Aluminum |
.098 |
13.2 |
1170 – 1210 |
All |
116 |
52 |
172 |
20 |
5052 Aluminum |
.097 |
13.2 |
1125 – 1200 |
All |
80 |
35 |
116 |
30 |
5083 Aluminum |
.096 |
13.2 |
1095 – 1180 |
0 |
81 |
29 |
98 |
36 |
5086 Aluminum |
.096 |
13.2 |
1085 – 1185 |
All |
73 |
31 |
104 |
33 |
Heat Treatable |
||||||||
2011 Aluminum |
.102 |
12.7 |
1005 – 1190(5) |
T3 |
88 |
39 |
123 |
27 |
|
|
|
|
T8 |
99 |
45 |
142 |
23 |
2014 Aluminum |
.101 |
12.8 |
945 – 1180(4) |
0 |
112 |
50 |
159 |
21 |
|
|
|
|
T4 |
78 |
34 |
108 |
31 |
|
|
|
|
T6 |
89 |
40 |
127 |
26 |
2017 Aluminum |
.101 |
13.1 |
955 – 1185(4) |
0 |
112 |
50 |
159 |
21 |
|
|
|
|
T4 |
76 |
34 |
108 |
31 |
2024 Aluminum |
.100 |
12.9 |
935 – 1180(4) |
0 |
112 |
50 |
160 |
21 |
|
|
|
|
T3, T4, T361 |
70 |
30 |
96 |
35 |
|
|
|
|
T6, T81, T861 |
88 |
38 |
122 |
27 |
6013 Aluminum |
.098 |
13.0 |
|
T651 |
95 |
|
|
|
6020 Aluminum |
.098 |
13.2 |
|
T8, T9 |
|
|
|
|
6061 Aluminum |
.098 |
13.1 |
1080 – 1205(5) |
0 |
104 |
47 |
155 |
22 |
|
|
|
|
T4 |
89 |
40 |
132 |
26 |
|
|
|
|
T6 |
96 |
43 |
142 |
24 |
6063 Aluminum |
.097 |
13.0 |
1140 – 1210 |
0 |
126 |
58 |
191 |
18 |
|
|
|
|
T1 |
112 |
50 |
165 |
21 |
|
|
|
|
T5 |
121 |
55 |
181 |
19 |
|
|
|
|
T6, T83 |
116 |
53 |
175 |
20 |
6101 Aluminum |
.097 |
13.0 |
1150 – 1210 |
T6 |
126 |
57 |
188 |
18 |
|
|
|
|
T61 |
128 |
59 |
194 |
18 |
|
|
|
|
T63 |
126 |
58 |
191 |
18 |
|
|
|
|
T64 |
131 |
60 |
198 |
17 |
|
|
|
|
T65 |
126 |
58 |
191 |
18 |
7075 Aluminum |
.101 |
13.1 |
890 – 1175(6) |
T6 |
75 |
33 |
105 |
31 |
Reference Thyssenkrupp (delivering Aluminum materials and supply chain solutions to aerospace companies throughout the Americas, Asia Pacific, Europe and North Africa)