Ceramic material data AD-85

Parameter Specification Units Test AD 85
Specific weight     ASTM C20-70 3.41
Hardness Rockwell 45N [Gpa] ASTM E18-67 73
  Knoop   1000g-load 9.8
Surface like burned [µm] Profilometer 1.6
  ground     1
  polished     0.2
Crystal size avarage bandwidth [µm]   2 to 12
Water absorption /     ASTM C373-72 no
Gas permeability** /       no
Color       white
Compressive strength 25°C [MPa] ASTM C773-74 1930
Flexural strength 25°C [MPa] ASTM f417-75T 296
  1000°C [MPa]   172
Tensile strength 250°C   ACMA TEST #4 155
Elasticity   [GPa]   221
Poisson number       0.22
Max. operation temperature (without load) [°C]   1400
Linear thermal expansion 25-25°C [10-6/°C] ASTM C372-56 3.4
  25-200°C     5.3
  25-500°C     6.2
  25-800°C     6.9
  25-1000°C     7.2
  25-1200°C     7.5
Thermal conductivity 20°C [W/m*K] ASTM C408-58 14.6
  100°C     12.1
  400°C     6.7
  800°C     4.2
Spezific heat capacity / (100°C) [J/kg*K] ASTM C351-61 920
Dielectric strength 6,35 mm [ac-kv/mm] ASTM D116-69 9.4
  3,18 mm     13.4
  1,27 mm     17.3
  0,64 mm     21.6
  0,25 mm     28.3
Permittivity 1 kHz   ASTM D150-70 8.2
  1 MHz   ASTM D2520-70 8.2
  100 MHz     8.2
Electrical loss 1 kHz   ASTM D150-70 0.011
  1 MHz   ASTM D2520-70 0.007
  100 MHz     0.007
Volume resistivity 25°C [ohm*cm²/cm] ASTM D1829-66 >1014
  300°C     4.6*1010
  500°C     4,0*108
  700°C     7.0*106
  1000°C     ----
  1. Measurement recording:
    The measurements were carried out using customary measuring
    methods and, unless otherwise stated, at room temperature.

  2. Composition monitoring:
    All Coorstek ceramic components are manufactured and controlled using the latest
    chemical, spectrographic and radiographic methods.

  3. Chemical Resistance:
    Although Coorstek components have high chemical resistance, we recomend to submit
    specific data on this to Coorstek to optimize design and material selection.
  • * The properties of ceramic molded parts vary in part with the way they are
    manufactured, their shape and size. A specification allows the majority of the
    required characteristic data to be met in the long term.
  • ** No helium penetration through a 25.4 mm diameter and 0.25 mm thick plate,
    measured at 3*10-7 Torr vacuum against 1 bar helium, 15 sec. at room temperature.