Ceramic-to-metal seals
Assembly methods for microwave tubes and devices

Hard metallization

A metal deposit is first firmly attached to the ceramic surfaces to be sealed, and then brazed on in the same way as a metal part.

Active metal sealing

In this case, the bond is obtained by using a number of special metal alloys that are chemically highly reactive in the liquid state, and capable of reducing the surface of the oxides making up the ceramic with which they are in contact, thus forming an interfacial compound firmly bonded to the ceramic.

Enamel sealing

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