Providing excellent electrical properties and easily machined, our MACOR® Machinable Glass Ceramic (MGC) is frequently used to create hermetic seals and electrically insulating feedthroughs.
MACOR® machinable glass ceramic offers exceptional electrical properties and as such it has become the natural choice within electrical insulation applications. We often utilise conductive materials through our MACOR® machinable glass ceramic requiring our MACOR® MCG feedthroughs to be sealed without sacrificing strength, hermeticity and high use temperature.
Whilst there are many sealing materials, we employ a range of sealing glasses to ensure that desirable properties are achieved without compromising effectiveness.
|Ferro Code1||Firing Cycle2||Continuous use temperature (°C)||Coefficient of Thermal Expansion|
|7555*||450°C-20 min.||300||88.5 x 10-7/°C|
|7570*||470°C-30 min.||330||84 x 10-7/°C|
|7572||450°C-60 min.||425||95 x 10-7/°C|
|7575||450°C-60 min.||425||89 x 10-7/°C|
1 Ferro Corporation, PO Box 6550, 4150 E. 56th Street, Cleveland OH, 44101. Tel. (216) 641-8585, ext. 7426, Fax (412) 641-8857.
2 These are idealised conditions. Heating and cooling rates and soak times are dependent on the size and geometry of the parts. The time is the hold at the corresponding temperature.
* Vitreous solder glass.
MACOR® machinable glass ceramic (corning code 9658) can be used to hermetically seal glass, ceramic or metal due to its high glass content.
This glass content combined with a high coefficient of thermal expansion makes it possible to seal MACOR® to a wide range of different metals and glasses.
Using solder glass frit it is possible to achieve vacuum tight seals which can be used at high temperatures. MACOR® machinable glass ceramic and solder glass frit can be sealed to the following:
- Chrome-iron stainless
- 52% nickel alloys
- Sylvania #4