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Material properties

Learn more about the integral components of our ceramic heating element.

Technology / Material properties

Material properties of our fully ceramic heating elements

Our 100% ceramic heating elements made from silicon nitride and aluminum nitride have a number of advantages in comparison to metallic heating elements. Owing to the low thermal capacity of the material due to its low-density, ceramic material has a low heat capacity and therefore is well suited to handle temperatures up to 1 000 °C with very little energy consumption.

This extraordinary technology, which implements ceramic material able to conduct electricity uniformly sintered with an insulated ceramic housing, is able to deliver high performance consistently. Highly resistant to wear and oxidation, these ceramics guarantee outstanding durability and long life as well.


Basic Material

Parameter Scale unit Si3N4 AlN
max. temperature (Tmax)  °C 1 000 1 000
thermal conductivity (λ) W/mK 40 140
temperature shock resistance (ΔT) K 500 400
emissivity (1100 °C) (ε) - 0.96 0.90
Young's modulus (E) GPa 320 310
bending strength (δBB) MPa 400 200
compressive strength (δD) MPa 2 000 1 200
coefficient of thermal expansion (α) 10-6 K-1 3 5
density (ρ) g/cm³ 3.21 3.26
specific heat (cp) J/kgK 750 740
porosity (100 - % t.D.) % 0 0
critical stress intensity factor (KIc) MPa m½ 6 3.3
Weibull – modulus (m) - 7.9 6

The thermal shock resistance depends on the geometric shape of the heater.


Surface load

Parameter Scale unit Value
in still air W/cm2 15
in moving air (40 m/s) W/cm2 25
in water W/cm2 70
maximum W/cm2 150

Electrical parameters

Parameter Scale unit Si3N4 AlN
resistivity Ω cm 5 · 10-3 - 5 · 10-1 5 · 10-3 – 2 · 10-1
isolation resistivity Ω mm (20 °C) 1013 1013
dielectric strength kV/mm 25 25

Emission spectrum

Fully ceramic heating elements are long-wave infrared heaters with a maximum emission of 5 to 10 µm and a radiation coefficient of ε > 0.9.

Advantages in comparison

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The high compressive strength of 2 000 MPa and the high Young's modulus of 300 GPa of the Silicon nitride ceramic material are maintained at temperatures up to 1 000 °C. There is hardly any self-deformation.

  • temperatures up to 1 000 °C
  • remarkable mechanical strength
  • integrated vacuum channels/Drilled holes
  • heated areas from 1 mm2 up possible
  • heated area formed to the contour of the product to be heated