Resistive Wires:

The resistivity and maximum operating temperature are the most important characteristics of a resistive wire. The higher the resistivity, the thicker the gauges with which a given resistance is obtained and therefore its useful life is longer. Likewise, the higher the maximum operating temperature, the higher the surface load (W/cm²) will be supported. Notwithstanding the temperature required in each particular application and the area available to accommodate the resistance will determine the wire to be used.

  • Kanthal:

Swedish brand founded in 1931. Its founder invented resistive wires based on the FeCrAl alloy that is the basis of most resistive wires used today.

Origin: Sweden
Reference: D

Density [g/cm³]  7.25
Resistivity at 20°C [Ω mm²/m]  1.35
Melting Point [°C]  1500
Maximum Continuous Operating Temperature in air [°C] 1300


C (%) Max  0.08
Si (%) Max  0.7
Mn (%) Max  0.5
Cr (%) Min-Max  20.5-23.5
Al (%) Nominal  4.8
Fe (%)  Balance

Cross Section: Circular, 0.10mm to 5.00mm.

  • L&R:

    This supplier supplies us with resistive wires continuously since the beginning of the century.

    Origin: China
    References: OCr21Al4, OCr21Al6, OCr21Al7Mo2

Reference  OCr21Al4  OCr21Al6 OCr21Al7Mo2
Density [g/cm³]  7.35 7.16 7.1
Resistivity at 20°C [Ω mm²/m]  1.23 1.42 1.53
Melting Point [°C]  1500 1500 1520
Maximum Continuous Operating Temperature in air [°C]  1100 1250 1400


Reference OCr21Al4 OCr21Al6 OCr21Al7Mo2
Cr (%) Min-Max 18-21 19-22 21-23
Al (%) Min-Max 3-4.2 5-7 5-7
Mo (%) - - 1.8-2.2
Fe (%) Balance Balance Balance

Cross Section:

OCr21Al4: Rectangular, 0.9X0.06mm a 7.0x0.20mm.
OCr21Al6 y OCr21Al7Mo2: Circular, 0.10mm a 5.00mm.