Ceradyne manufactures a family of particulate composites called “lossy” ceramics, whose purpose is to selectively absorb microwave energy of unwanted frequencies enabling the tube to produce energy at the desired frequency. These composites have tailored dielectric and loss properties to allow them to be matched to specific microwave tube applications.

The Ceralloy® 6700 family of MgO-SiC compositions are designed to absorb microwave energy in very specific frequency ranges.

The Ceralloy® 7700 family of Al2O3-SiC compositions, Ceralloy® 13700 AlN-SiC compositions and the Ceralloy® 137 AlN based composites are broadband absorbers. The AlN composites have high thermal conductivities designed to aid in heat dissipation within the microwave tube.

The materials are used in various microwave tube applications including:

• Absorbers
• Load Pellets
• Terminations
• Severs