Physical Properties

 PROPERTY

TEST UNIT

 P440

Porcelain

HF300
STEATITE

S145

STEATITE

 C5

CORDIERITE

 R197

REFRACTORY

R200

REFRACTORY

R250

PURE MgO

 COLOUR

WHITE

CREAM

GREY

WHITE / CREAM

DARK CREAM

LIGHT BROWN

 DENSITY

 Grams/cm³

2.4

2.6

2.3

 2.0

 2.2

3.3

POROSITY

 %

NIL

NIL

NIL

POROUS

POROUS

N.A

 CROSS BENDING

STRESS

MN/m²

1cm diam.sample

 82.74

124.11

 75.84

 48.26

 44.82

N.A

COMPRESSIVE STRENGTH

MN/m²

1cm diam.sample

482.63

750.42

698.48

 275.79

262.0

N.A

TENSILE STRENGTH

MN/m²

 48.26

 55.16

–

–

–

N.A

 PERMITIVITY

5-4

 6

5-7

–

–

 –

POWER

1KHz :

 80-100

 35

 –

–

 –

–

 FACTOR

1MHz : x 10^-4

“

 30

70

 –

–

–

10MHz:

“

32

 –

 –

 –

–

 20°^C

>10¹⁴

>10¹⁴

>10¹⁴

 dry >10¹²

 dry >10¹⁴

dry >10¹⁴

 300°^C

 6 x 10⁶

3 x 10⁷

5 x 10⁸

5 x 10⁸

10⁹

10¹³

RESITIVITY

Ω/CM³ @ :

600°^C

3 x 10⁴

10⁵

7 x 10⁵

10⁶

 10⁷

10¹⁰

900°^C

2 x 10³

7 x 10³

2 x 10⁵

10³

 10⁵

10⁸

DIELECTRIC STRENGTH

KVmm

@ 20 °^C sample

thickness 5mm

25

24

–

–

25

–

 THERMAL CONDUCTIVITY

 W/m/K

@375-1200

2.06

@375-1000

1.91

 @300-400

3.26

 HARDNESS

MOHS

7-8

7-8

7

6

6

–

 COEFFICIENT of LINEAR EXPN.

X 10^-6 @

20-800°^C

6.5

 7.5

2.6

4.0

4.5

–