PHYSICAL PROPERTIES
CHEMICAL PROPERTIES
Physical Properties:
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/°F/ft | about 0.31 | about 0.24 | |
| Parallel to cleavage planes | Gm.cal/sec/cm2/ °C/cm | about 0.012 | |
| BTU/hr/ft2/°F/ft | about 3.0 | ||
| Percentage of water 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 |
Chemical Properties:
| Silica (SiO2) | 45.57% |
| Alumina (Al2O3) | 33.10% |
| Potassium Oxide (K2O) | 9.87% |
| Ferric Oxide (Fe2O3) | 2.48% |
| Sodium Oxide (Na2O) | 0.62% |
| Titanium Oxide (TiO2) | Traces |
| Calcium Oxide (CaO) | 0.21% |
| Magnesia (MgO) | 0.38% |
| Moisture at 100°C | 0.25% |
| Phosphorus (P) | 0.03% |
| Sulphur (S) | 0.01% |
| Graphite Carbon (C) | 0.44% |
| Loss on Ignition (H2O) | 2.74% |