|
Characteristic
|
Unit
|
Muscovite
|
Phlogopite
|
| Colour |
|
Ruby
/ Green |
Amber
/ Yellow |
| Density |
gm/cm3 |
2.6
- 3.2 |
2.6-3.2 |
| lb/ln3 |
0.095
- 0.116 |
0.095-0.116 |
| Specific
Heat |
|
0.21 |
0.21 |
| Hardness |
Moh
Scale |
2.8
- 3.2 |
2.3
- 3.0 |
| Shore
Test |
80
- 105 |
70
- 100 |
| Optic
Axial Angle |
|
55
- 75 |
5
- 25 |
| Tensile
Strength |
kgf/cm2 |
about
1750 |
about
1000 |
| lbf/in2 |
about
25000 |
about
15000 |
| Shear
Strength |
kgf/cm2 |
2200
- 2700 |
1000
- 1300 |
| lbf/in2 |
31000
- 38000 |
14000
- 19000 |
| Compression
Strength |
kgf/cm2 |
1900
- 2850 |
|
| lbf/in2 |
27000
- 32000 |
|
| Modulus
of Elasticity |
kgf/cm2
x 10-3 |
1400
- 2100 |
1400
- 2100 |
| lbf/in2
X 10-6 |
20
- 30 |
20
-30 |
| Coefficient
of expansion per ° C perpendicular to cleavage plane |
|
9
X 10-6 - 36 X 10-6 |
30
X 10-6 - 60 X 10-6 |
| Calcining
Temperature |
C |
700
- 800 |
900
- 1000 |
| F |
1290
- 1470 |
1650
- 1830 |
| Maximum
operating temperature |
C |
500
- 600 |
800
- 900 |
| F |
930
- 1110 |
1470
- 1650 |
| Thermal
conductivity |
|
|
|
| Perpendicular
to cleavage planes |
Gm.cal/sec/cm2/C/cm |
about
0.0013 |
about
0.0001 |
| BTU/hr/ft2/0f/ft |
about
0.31 |
about
0.24 |
| Parallel
to cleavage planes |
Gm.cal/sec/cm2/C/cm |
|
about
0.012 |
| BTU/hr/ft2/0f/ft |
|
about
3.0 |
| Water
of constitution % |
|
4.5 |
3.0 |
| Moisture
absorption |
|
Very
low |
Very
low |
| Apparent
electric strength |
0.001"
to 0.003" KV/mm |
120
- 200 |
|
| thick
Volts per 0.001" |
3000
- 5000 |
|
| R.M.S.
at 15° C (60° F) |
0.01"
to 0.05" KV/mm |
40
- 80 |
30
-60 |
| thick
Volts per 0.001" |
1000
- 2000 |
750
-1500 |
| Permittivity
at 15° C (60 F) |
|
6
- 7 |
5
- 6 |
| Power
Factor (loss tangent) |
@
15° C (60° F) |
0.0001
- 0.0004 |
0.001
- 0.005 |
| Volume
Resistivity |
25°
C (77° F) ohm cm |
40
x 1013-2 x 1017 |
1
x 1012 - 1 x 1012 |
| Acid
reaction |
|
Affected
by Hydrofluoric Acid |
Affected
by Sulphuric Acid |
