Macor machinable glass ceramic was originally designed for NASA’s space shuttle to prevent thermal transfer from the exterior to the inside of the vehicle. It was used in the window frames of the space shuttle because of its electrical and heat insulating qualities; because of its radiation resistance and non-porosity (it has a porosity of zero); and because it emits no vapors (toxic or otherwise) of any kind, especially at the lower pressures that were found in spacecraft. Macor is an excellent material for high vacuum applications, such as electron microscopy, because when properly baked out, it cannot outgas at any achievable vacuum level. Electronics / Semiconductors Precision coil formers (high precision and dimensionally stable) High voltage insulators (smooth surface finish and unaffected by arcing) Laser Applications Spacers, cavities and reflectors in laser assemblies (precision finish and heat resistant) High Vacuum Applications Thermal breaks in high temperature processing equipment. Coil supports and vacuum feed-throughs (vacuum stable and hermetically sealable) Aerospace / Space Industry Retaining rings on hinges, windows and doors of NASA’s Space Shuttle Supports and components in several satellite borne systems (thermally and electronically insulating) Nuclear Industry Fixtures and reference blocks in power generation units (dimensionally unaffected by irradiation)