Kanthal is a world-leading brand for products and services in the area of industrial heating technology and resistance materials.

Kanthal APM (Resistance heating wire and resistance wire)

Datasheet updated 2012-06-20 15:01:07 (supersedes all previous editions)

Kanthal APM is an advanced powder-metallurgical, dispersion-strengthened, ferritic iron-chromium-aluminium alloy (FeCrAl alloy) for use at temperatures up to 1425°C (2600°F). The alloy is characterized by exceptionally good form stability and oxidation resistance.

Kanthal APM has low tendency to ageing and low resistance change. It has excellent surface oxide properties, which gives good protection in corrosive atmospheres as well as in atmospheres with high carbon potential, and no scaling.

The unique combination of excellent oxidation properties and formstability contributes to long element service life. The alloy's superior form stability reduces the amount of element support.

Typical applications for Kanthal APM are in high-temperature furnaces for firing of ceramics, heat treatment, in laboratory furnaces, in furnaces for electronic industries and in diffusion furnaces.

Chemical composition

C % Si % Mn % Cr % Al % Fe %
Nominal composition 5.8 Bal.
Min - - - 20.5 -
Max 0.08 0.7 0.4 23.5 -

Mechanical properties

Wire size Yield strength Tensile strength Elongation Hardness
Ø Rp0.2 Rm A
mm MPa MPa % Hv
4.0 470 680 20 230

Mechanical properties at elevated temperature
Temperature °C 900 1000 1100 1200 1300
MPa 40 23 16 12 9

Ultimate tensile strength - deformation rate 6.2 x 10-2/min

Creep strength - 1% elongation in 1000 h
Temperature °C 800 900
MPa 8.2 3.5

Creep strength - 0.1% elongation in 1000 h
Temperature °C 1100 1200 1300 1400
MPa 2.3 1.2 0.7 0.4
Creep rupture strength
Time 800°C 1472°F 1000°C 1832°F 1200°C 2192°F 1400°C 2552°F
h MPa psi MPa psi MPa psi MPa psi
100 15.0 2176 5.6 812 3.3 478 1.3 189
1000 11.3 1640 3.4 478 1.6 232 0.5 72
10000 8.2 1190 2.2 320 0.7 100 0.2 30

The data in the tables apply to material with fine grain structure in the temperature range from 800°C to 900°C,
and to material with coarse grain structure in the temperature range from 1100°C to 1400°C.
In the delivery state KANTHAL APM always has a fine grain structure. After use for a certain period of time , the grain size becomes coarse.

Physical properties

Density g/cm3 7.10
Electrical resistivity at 20°C Ω mm2/m 1.45
Poisson's ratio 0.30

Young's modulus
Temperature °C 20 100 200 400 600 800 1000
GPa 220 210 205 190 170 150 130

Temperature factor of resistivity
Temperature°C 100 200 300 400 500 600 700 800 900 1000 1100 1200 1300 1400
Ct 1.00 1.00 1.00 1.00 1.01 1.02 1.02 1.03 1.03 1.04 1.04 1.04 1.04 1.05

Coefficient of thermal expansion
Temperature °C Thermal Expansion x 10-6/K
20 - 250 11
20 - 500 12
20 - 750 14
20 - 1000 15
20-1200 16
20-1400 16

Thermal conductivity
Temperature °C 50 600 800 1000 1200 1400
W m-1 K-1 11 20 22 26 27 35

Specific heat capacity
Temperature °C 20 200 400 600 800 1000 1200 1400
kJ kg-1 K-1 0.46 0.56 0.63 0.75 0.71 0.72 0.74 0.80
Melting point °C 1500
Max continuous operating temperature in air °C 1425
Magnetic properties The material is magnetic up to approximately 600°C (Curie point).
Emissivity - fully oxidized material 0.70

Disclaimer: Recommendations are for guidance only, and the suitability of a material for a specific application can be confirmed only when we know the actual service conditions. Continuous development may necessitate changes in technical data without notice. This datasheet is only valid for Kanthal materials.

Article functions

Related information

Contact us

Print this datasheet

Export to PDF

Download this datasheet as PDF or send by email.
Download as PDF

Contact us