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>High Density Carbon & Graphite Materials
Specifications
High
density graphite is a very versatile material, and is used in a wide
range of applications. Ceramisis offers a complete range of high
density graphites to suit every application where graphite materials
are required. Our state of the art CNC manufacturing facility can
machine graphite components to the highest tolerances. We can cater
for both small quantity and high volume orders.
The main
properties of graphite are:
·
Ability to withstand very high
temperatures up to 2800 C (inert atmosphere or in vacuum)
·
Good thermal shock resistance
·
Self lubricating
·
High compressive strength
·
Good chemical resistance
·
Dimensionally stable
·
Low expansion coefficient
·
Strength increases with temperature
·
Low friction coefficient
·
Electrically conductive
·
Will start to oxidise in air at 450 C
The
materials properties can be further enhanced by applying
impregnations, or coatings. The following impregnations and coatings
are available:
·
Phosphate impregnation for increased
oxidation and wear resistance
·
Boron
inclusion for increased oxidation and
wear resistance
·
Metal
impregnation for increased strength and
reduced porosity
·
Resin
impregnation for reduced porosity at
low temperatures
·
Pitch
densification for reduced porosity at
high temperatures
·
Vitreous impregnation to eliminate
particles
· Vitreous coating for reduced porosity, eliminate particles and give a highly polished finish
· Pyrolytic Graphite coating for zero porosity and particles, electrically conductive.
· Boron Nitride coating for zero porosity and particles, increased oxidation resistance to 900C in air, electrical insulator.
· Silicon Carbide coating for zero porosity and particles, increased oxidation resistance to 1500C in air, increased chemical resistance, very hard coating, electrical insulator.
General
purpose graphite
|
Main Characteristic |
General purpose low spec |
General purpose low spec |
General purpose mid spec |
General purpose high spec |
General purpose high spec |
|
Grade |
GP10 |
GP15 |
GP20 |
GP25 |
GP30 |
|
Average grain size- microns |
15 |
15 |
12 |
5 |
8 |
|
Density - g/cc |
1.78 |
1.78 |
1.79 |
1.83 |
1.86 |
|
Porosity- % |
10% |
11% |
11% |
10% |
8% |
|
Thermal Conductivity-W/mK |
85 |
115 |
92 |
69 |
68 |
|
CTE-microns/m.degC |
4.6 |
4.5 |
5.5 |
5.7 |
5.9 |
|
Flexural Strength- Mpa |
43 |
40 |
52 |
75 |
65 |
|
Compressive Strength- Mpa |
93 |
80 |
106 |
170 |
155 |
|
Youngs Modulus - Gpa |
9.2 |
9.9 |
10 |
13 |
12 |
|
Shore Hardness |
53 |
52 |
62 |
79 |
76 |
|
Resistivity- uOhm cm |
1600 |
1100 |
1340 |
1540 |
1640 |
|
Max operating temp- in air |
500 deg C |
500 deg C |
500 deg C |
500 deg C |
500 deg C |
|
-in vacuum |
2200 degC |
2200 degC |
2200 degC |
2200 degC |
2200 degC |
|
-in innert gas |
2000 degC |
2000 degC |
2000 degC |
2000 degC |
2000 degC |
Specialist
Graphite Grades
|
Main Characteristic |
Densified |
High thermal conductivity |
High electrical reststivity |
High strength & expansion |
High strength & expansion densified |
Ultra fine grained high expansion |
|
Grade |
SPG35 |
SPG40 |
SPG45 |
SPG50 |
SPG55 |
SPG60 |
|
Average grain size- microns |
13 |
10 |
5 |
4 |
4 |
<1 |
|
Density - g/cc |
1.88 |
1.82 |
1.65 |
1.77 |
1.77 |
1.79 |
|
Porosity- % |
4% |
10% |
25% |
20% |
4% |
20% |
|
Thermal Conductivity-W/mK |
111 |
140 |
75 |
95 |
95 |
72 |
|
CTE-microns/m.degC |
5 |
4.8 |
7.7 |
8.1 |
8.1 |
8.1 |
|
Flexural Strength- Mpa |
57 |
54 |
53 |
85 |
85 |
110 |
|
Compressive Strength- Mpa |
126 |
90 |
105 |
140 |
140 |
195 |
|
Youngs Modulus - Gpa |
12.6 |
11 |
9 |
11 |
11 |
14.5 |
|
Shore Hardness |
65 |
55 |
68 |
74 |
74 |
85 |
|
Resistivity- uOhm cm |
1170 |
900 |
1900 |
1500 |
1500 |
1750 |
|
Max operating temp- in air |
500 deg C |
500 deg C |
500 deg C |
500 deg C |
500 deg C |
500 deg C |
|
-in vacuum |
2200 degC |
2200 degC |
2200 degC |
2200 degC |
2200 degC |
2200 degC |
|
-in innert gas |
2000 degC |
2000 degC |
2000 degC |
2000 degC |
2000 degC |
2000 degC |
Oxidation
Resistant Graphite Grades
|
Main Characteristic Oxidation resistant plus: |
Boronised wear resistant |
Phosphated high strength |
Phosphated high thermal conductivity |
Phosphated General purpose mid spec |
Phosphated General purpose high spec |
|
Grade |
HTBG210 |
HTG300 |
HTG350 |
HTG400 |
HTG450 |
|
Average grain size- microns |
10 |
5 |
10 |
13 |
5 |
|
Density - g/cc |
1.85 |
1.87 |
1.82 |
1.85 |
1.86 |
|
Porosity- % |
10% |
21% |
10% |
11% |
10% |
|
Thermal Conductivity-W/mK |
30 |
60 |
140 |
85 |
70 |
|
CTE-microns/m.degC |
4.6 |
7.8 |
4.8 |
5.2 |
5.5 |
|
Flexural Strength- Mpa |
70 |
96 |
54 |
50 |
84 |
|
Compressive Strength- Mpa |
120 |
185 |
90 |
130 |
208 |
|
Youngs Modulus - Gpa |
20 |
11 |
11 |
14 |
13 |
|
Shore Hardness |
60 |
94 |
55 |
65 |
85 |
|
Resistivity- uOhm cm |
1300 |
2000 |
900 |
1200 |
1550 |
|
Max operating temp- in air |
800 deg C |
600 deg C |
600 deg C |
600 deg C |
600 deg C |
|
Max continuous operating temp in air |
600 deg C |
550 deg C |
550 deg C |
550 deg C |
550 deg C |
|
