Swallow offer a comprehensive
range of aluminium oxide insulators together with
many other specialised components.
A range of beryllium oxide and
aluminium nitride components is also available from
stock.
Aluminium Oxide Insulators
As-fired parts have a tolerance of ±0.2mm on
dimensions up to 10mm and ±2% over 10mm.
Flatness: As-fired parts have
a maximum bow of 0.15mm per 25mm. To improve thermal
contact, we offer ground parts with a flatness greater
than 0.012mm per 25mm.
View
illustrated ceramic components
- The majority of components illustrated
are available from stock.
| Properties |
Unit |
SP96 |
SP99.4 |
SP999 |
| Purity |
% AI2O3 |
96 |
99.4 |
99.95 |
| Colour |
|
White |
Ivory |
White |
| Density |
g/cm3 |
>3.70 |
3.86 |
3.92 |
| Open porosity |
% |
0 |
0 |
0 |
| Grain size |
Micrometres |
8-10 |
3-5 |
3-5 |
| Flexural strength |
N/m2 |
300.106 |
350.106 |
350.106 |
| Hardness |
Mohs scale |
8-9 |
9 |
9 |
|
Vickers HV1 |
2200 |
2300 |
2400 |
| Surface finish:
as fired
machined
polished |
Ra(um) |
0.7
0.6
0.1 |
0.3
0.25
0.05 |
-
-
- |
|
| Specific heat |
J.kg-1oK-1 |
1068 |
1072 |
1072 |
Thermal conductivity
W.m.-1º/K-1
|
25oC
300o
500oC |
20.5
15.5
12.2 |
37.7
21.0
16.8 |
-
-
- |
| Linear thermal expansion coefficient |
oC 25-300
oC 25-600
oC 25-800 |
6.3x10-6
8.0x10-6
8.6x10-6 |
6.3x10-6
7.1x10-6
7.3x10-6 |
6.3x10-6
7.1x10-6
7.3x10-6 |
| Maximum working temperature |
oC |
1200 |
1600 |
1700 |
| Dielectric strength |
KV/mm |
>18 |
>20 |
>20 |
| Resistivity |
ohm-cm |
>1014 |
>1014 |
>1014 |
| Permittivity (25ºC) |
1MHz
10MHz
10GHz |
9.07
9.04
8.98 |
9.9
-
- |
_
-
- |
| Dissipation factor (tan d)(at 25ºC) |
1MHz
10MHz
10GHz |
2.6 x 10-4
6.2 x 10-4
7.8 x 10-4 |
1.0 x 10-4
1.0 x 10-4
10.0 x 10-4 |
_
-
- |
View
illustrated ceramic components
- The majority of components illustrated
are available from stock.
