Ceramic-metalizing tape for reliable metal-ceramic seals

A ceramic-metalizing method was developed which increases the reliability of hard-soldered metal-ceramic seals and makes production automation possible. The new technique utilizes a "metalizing tape" consisting of a self-supporting plastic tape which contains the metalizing powders and a suitable binder (methacrylic-type). This tape can be manufactured with extremely uniform thickness, density and surface smoothness, all of which qualities can be controlled on the prefabricated tape prior to its usage. The application of the prefabricated metalizing tape to the ceramic surface can be accomplished in a very simple way: by using a suitable solvent to form a bond between the metalizing tape and the ceramic, or by thermal sealing. The materials and the methods used for the preparation of the metalizing tape are described, as well as the methods of application. The resulting extremely uniform metal coating on the ceramic makes it possible to investigate the effect of metalizing thickness and of different materials on the bond strength and on the vacuum qualities of metal-ceramic butt seals.