What is Mica Types of Mica
Properties of Mica
Properties
Units
Muscovite
Phlogopite
Color
Ruby/ Green/ White
Amber/ Silver/Green
Density
gm/cm3
2.6 - 3.2
Specific heat
0.21
0.20
Hardness
Moh scale
2.8 - 3.2
2.3 - 3.0
Shore Test
80-105
70-100
Breakdown voltage
KV/mm
120 - 200
-
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
Thermal conductivity perpendicular to cleavage plane
Gm.cal/sec/cm2/°C/cm
about 0.0013
about 0.0010
BTU/hr/ft2/0f/ft
about 0.31
about 0.24
Thermal conductivity parallel to cleavage plane
about 0.012
about 3.0
Water of Constitution %
4.5
3.0
Moisture Absorption
Very low
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
Insulation resistence
x1013ohm/cm
4-20000
0.1 - 10
Calcining temp
°C
700-800
900-1000
Max. operating temp
500-600
800-1000
Optic axial angle
degrees
55 - 75
5 -25
Tensile strength
MN/m2
175
1000
Shear strength
220 - 270
1000-1300
Compression strength
190 - 285
Modulus of Elasticity
Kgfcm2 x 10-3
lbf/in2 x 10-6
1400 – 2100
20 - 30
20 – 30
Loss tangent
x10-4
1-4
10-50
Permittivity at 15°C (60°F)
6 - 7
5 -6
