Mechanical & Physical Properties of
Conductor Materials (Average Values)

COPPER

ALUMINUM

Melting Point°F
Melting Point°C

1981
1083

1215
657

Density, lb/cu. in
Tensile Strength, ksi

0.323
35

0.0977
15

Thermal Conductivity @ 68°F
Btu/sq. ft./ft./hr./°F

224

135

Electrical Resistivity @ 68°F
ohm-cir mil/ft

10.37

16.96

Linear Coeficient of Expansion
(68-212°F) micro in./in.°F

9.4

13.1

Special Heat
Btu/lb.°F

0.092

0.215

Breaking strength
Bare copper and aluminum wire

Size
AWG

HARD DRAWN

MEDIUM HARD DRAWN COPPER
3/4 HARD DRAWN ALUMINUM

SOFT ANNEALED COPPER
HALF HARD ALUMINUM

Approx.
Breaking Weight
in Pounds

Breaking Weight
in Pounds

Approx.
Breaking Weight
in Pounds

Min.

Avg.

Max.

CU

AL

CU

AL

CU

AL

CU

AL

CU

AL

18..
16..
14..

12..
10..
9..

8..
6..
4..

3..
2..
1..

1/0..
2/0..
3/0..

4/0..

85...
135..
213..

337..
529..
661..

826..
1281..
1970..

2439..
3003..
3687..

4518..
5518..
6722..

8144..

32...
54...
92...

144...
212...
262...

324...
495...
768...

971...
1225...
1542...

1950...
2460...
3100...

3900...

68..
106..
167..

262..
410..
514..

644..
1010..
1580..

1984..
2450..
3024..

3730..
4598..
5677..

6980..

22.
32.
55.

87.
139.
175.

221.
351.
545.

703.
885.
1120.

1410.
1780.
2240.

2830.

72..
113..
178..

279..
439..
550..

689..
1082..
1697..

2129..
2632..
3254..

4020..
4964..
6166..

7562..

25.
38.
65.

103.
163.
206.

260.
412.
640.

826.
1040.
1315.

1660.
2100.
2640.

3320.

77..
120..
..189..

297..
468..
586..

735..
1155..
1814..

2274..
2815..
3484..

4310..
5330..
6590..

8144..

28.
42.
72.

113.
180.
226.

286.
454.
705.

910.
1145.
1450.

1825.
2305.
2900.

3660.

49.........
78.........
124.........

197.........
314.........
380.........

480.........
763.........
1213.........

1530.........
1929.........
2432.........

2984.........
3762.........
4745.........

5983.........

22.....
33.....
57.....

90.....
143.....
180.....

228.....
361.....
560.....

724.....
912.....
1150.....

1451.....
1831.....
2305.....

2910.....