|
CHEMICAL
COMPOSITION |
| Basic
elements in % |
Formula |
Percentage
(Approx.) |
| Silica |
SiO2 |
47-50% |
Alumina |
Al2O3 |
29-33% |
| Oxide
of Iron |
Fe2O3 |
2.5-4.5% |
| Titanium
Oxide |
TiO2 |
0.10-0.20% |
| Lime |
CaO |
0.08-2.0% |
| Magnesia |
MgO |
0.3-0.4% |
| Potash |
K2O |
9.0-12.0% |
| Soda |
Na2O |
1.0-2.5% |
| Phosphorous |
P2O5 |
Negligible |
| Sulfur |
S |
Negligible |
| Loss on ignition |
|
3.5% |
PHYSICAL
COMPOSITION |
| Property |
Approximate |
| Color
|
Transparent,
white, ruby |
| Shape |
Thin
flakes |
| Particle
size |
10-5000
microns depending
on grade |
| Aspect
ratio |
20-70 |
| Bulk Density |
0.17-0.29
gms/cc |
| Apparent
Density |
10-14
lbs/ft3 |
| Specific
Gravity |
2.8-3.0 |
| Hardness
(Moh's Scale) |
2.5-3.0 |
| pH
(BS 3483) |
7.5-9.5 |
| Water
Solubility
|
Virtually
insoluble |
| Oil
Absorption (BS 3483) |
60-75
gms oil/100 gms mica |
| Whiteness
(MgO) |
80-88% |
| Phericity
Factor |
0.01 |
| NOTE:
As Vermiculite is
a natural mineral,
the properties and
composition of supplied
material may vary
slightly from the
above. |
MECHANICAL
PROPERTIES
Tensile Strength
:
125X103
psi
Modulus of Elasticity
:
25 X 106
psi
|
ELECTRICAL PROPERTIES
Dielectric constant
(100 Hz):
6-6.7
Dissipation Factor
(100 Hz):
4.5-8.2 x 102
Volume resistivity
(Ohm-cm:
7.5-8.8 x 1010 |
OPTICAL
PROPERTIES
Refractive
Index
:
1.58
UV Visible absorption
:
Very strong
IR absorption :
Very strong |
THERMAL PROPERTIES
Coefficient of thermal
expansion:
- Normal to cleavage
: 9 x 106K1
- Parrel to cleavage
: 4 x 106K1
- Maximum temperature
: 8000C |
