Temperature coefficient

Temperature coefficients of different materials for calculating resistance


Temperature coefficient of electrical resistance

The temperature coefficient (temperature coefficient) of a resistor describes the change in its resistance value when the temperature changes from a reference temperature of 20 ° C

The following lists show the temperature coefficient of resistance of some materials at 20 °C

Pure metals



Aluminium (99,5 %)
0.004
Lead
0.0042
Iron (pure)
0.00657
Gold
0.0037
Copper (99,9 %)
0.00393
Nickel
0.006
Platinum
0.00392
Mercury
0.0009
Silver
0.0038
Tantalum
0.0033
Tungsten
0.0044

Alloys



Aldrey (AlMgSi)
  0.0036
Beryllium bronze (SnBe4Pb)
  0.0005
Manganin (Cu84Ni4Mn12)
±0.00004
Constantan (CuNi44)
±0.00001
Isaohm
±0.000003
Brass(CuZn37)
  0.0016
Soft iron (4 % Si)
  0.0009
Steel C15
  0.0057

Non-metals



Carbon
-0.0005
Graphite
-0.0002
Arc Coal
 0.0005
Germanium
-0.048
Silicon
-0.075

In the case of the conductor materials that are important in electrical engineering, copper and aluminum in the temperature range 0 °C to 50 °C, the value 0.4% per °C can be calculated for estimates.

Commercially available low-power resistors have the usual temperature coefficients in the range from 0.0001 to 0.0002 (100ppm to 200 ppm) per °C, Precision resistances are in the range of 0.00005 (50 ppm) per °C.

The linear temperature coefficient is given in this case with the prefix TK, e.g. TK100 for a resistance with 100 ppm per °C.