Thermal Expansion Coefficient (TEC)
The Thermal Expansion Coefficient for a given material is a measure of the fractional change in length per degree change in temperature. The coefficient itself slightly changes with temperature and is most commonly reported as an average value for the temperature range of interest, typically room temperature to 100° C. A ranking for a group of materials available from Hamilton Precision Metals follows.
| Metal Alloy |
TEC 106/° C |
Temperature Range |
| Shunt Manganin |
18.7 |
20° to 100°C |
| Phosphor Bronze A |
17.8 |
20° to 300°C |
| Beryllium Copper 25 |
17.5 |
20° to 200°C |
| SS 302/304/304L |
17.3 |
0° to 100°C |
| SS 305 |
17.3 |
0° to 100°C |
| Copper 102 |
17.0 |
20° to 100°C |
| SS 301 |
16.9 |
0° to 100°C |
| Nickel Silver 55-18 |
16.7 |
20° to 300°C |
| Cu-Ni 715 |
16.2 |
20° to 300°C |
| SS 316/316L |
16.0 |
0° to 100°C |
| Balco |
15.0 |
20° to 100°C |
| Constantan |
14.9 |
20° to 100°C |
| HPM Beryllium Nickel |
14.4 |
20° to 550°C |
| HPM 600 |
14.2 |
20° to 315°C |
| HPM 400 |
13.9 |
20° to 100°C |
| HPM 80/20 A - 80/20AL |
13.4 |
20° to 100°C |
| HPM Nickel 200/201/270 |
13.3 |
0° to 100°C |
| Evanohm®R/S |
13.0 |
20° to 100°C |
| Moly Permalloy |
12.7 |
25° to 200°C |
| HPM X 750 |
12.6 |
20° to 100°C |
| Havar |
12.5 |
0° to 50°C |
| HPM C-276 |
11.2 |
25° to 100°C |
| SS 410 |
11.0 |
0° to 100°C |
| SS 17-4 PH (HT) |
10.8 |
21° to 93°C |
| HPM 455 |
10.6 |
22° to 93°C |
| SS 430 |
10.5 |
0° to 100°C |
| SS 420 |
10.3 |
0° to 100°C |
| SS 17-7 PH |
10.3 |
21° to 93°C |
| Precision C |
10.1 |
30° to 200°C |
| HPM Ni 52 |
10.0 |
30° to 500°C |
| CP Titanium |
8.6 |
0° to 100°C |
| Precision C |
8.1 |
-45° to 65°C |
| HPM Ni 42 |
6.0 |
30° to 400°C |
| Rodar |
4.9 |
30° to 400°C |
| HPM Ni 36 |
1.05 |
20° to 200°C |
Electrical Resistivity
Resistivity characterizes a metal's inherent capacity to support the flow of electrical current. The measured resistivity is the inverse of electrical conductivity and is expressed in Microhm•cm.
Conversion to other common units for resistivity are as follows:
- 1 Microhm•cm = 6.015 ohms CMF (ohms circular mil per foot)
- 1 Microhm•cm = 4.724 ohms SMF (ohms square mil per foot)
A ranking for a group of metals available from HPM is as follows:
| Metal / Alloy |
Resistivity @ R.T. Microhm • cm |
| Copper 102 |
1.71 |
| HPM Nickel 270 |
7.5 |
| Beryllium Copper 25 |
7.8 |
| HPM Nickel 201 |
8.5 |
| HPM Nickel 200 |
9.5 |
| Phosphor Bronze A |
11.5 |
| Balco |
19.9 |
| HPM Beryllium Nickel |
28.7 |
| Nickel Silver 55-18 |
31.4 |
| Shunt Manganin |
38.1 |
| Cu-Ni 715 |
39.5 |
| HPM Ni 52 |
43.0 |
| Rodar |
49.0 |
| Constantan |
50.8 |
| HPM 400 |
51.0 |
| SS 420 |
55.0 |
| CP Titanium |
56.0 |
| SS 410 |
57.0 |
| Moly Permalloy |
59.0 |
| SS 430 |
60.0 |
| HPM Ni 42 |
70.0 |
| SS 301 |
72.0 |
| SS 302/304/304L |
72.0 |
| SS 305 |
74.0 |
| SS 316/316L |
74.0 |
| HPM 455 |
79.0 |
| SS 17-4 PH (HT) |
80.0 |
| HPM Ni 36 |
82.0 |
| SS 17-7 PH |
83.0 |
| Havar |
92.0 |
| Precision C |
102.0 |
| HPM 600 |
103.0 |
| HPM 80/20 A - 80/20 AL |
108.0 |
| HPM X 750 |
119.0 |
| HPM C-276 |
130.0 |
| Evanohm®R |
133.0 |
| Evanohm®S |
137.0 |
Thermal Conductivity
Thermal Conductivity describes the inherent capacity of a metal to support the flow of thermal energy. Thermal Conductivity is expressed in W/m•K (Watts per meter degree Kelvin).
Conversion to other common units of Thermal Conductivity are as follows:
- 1 W/m•K = .5782 BTU • FT/HR • FT2 • °F
- 1 W/m•K = .0024 Cal/cm.s. °C
A ranking for a group of metals available from HPM is as follows:
| Metal / Alloy |
W/m•K @ R.T. |
| Copper 102 |
390.0 |
| Beryllium Copper 25 |
105.0 |
| HPM Nickel 270 |
79.0 |
| HPM Nickel 201 |
74.0 |
| Phosphor Bronze A |
69.2 |
| HPM Nickel 200 |
67.0 |
| HPM Beryllium Nickel |
48.4 |
| Moly Permalloy |
34.6 |
| Cu Ni 715 |
29.4 |
| Nickel Silver 55-18 |
29.3 |
| Balco |
28.9 |
| SS 430 |
26.1 |
| SS 410/420 |
24.9 |
| HPM 400 |
21.8 |
| Constantan |
21.2 |
| Shunt Manganin |
19.8 |
| HPM 455 |
18.0 |
| SS 17-4 PH (HT) |
17.9 |
| Rodar |
16.7 |
| SS 17-7 PH |
16.7 |
| SS 301 |
16.3 |
| SS 302/304/304L |
16.3 |
| SS 316/316L |
16.3 |
| SS 305 |
16.2 |
| CP Titanium |
16.0 |
| HPM 80/20 A - 80/20 AL |
15.0 |
| HPM 600 |
14.8 |
| Evanohm®R/S |
14.6 |
| HPM Ni 52 |
14.0 |
| Precision C |
13.0 |
| Havar |
13.0 |
| HPM X 750 |
12.0 |
| HPM Ni 42 |
10.7 |
| HPM Ni 36 |
10.5 |
| HPM C-276 |
9.4 |