Low temperature metallization of debased alumina

Abstract

A 97% alumina has been metallized at 1000°C using refractory metals applied as oxides or in solution. Copper was used for brazing without nickel plating. The seals were 85% as strong as those metallized by the high temperature process. Optical microscopy, X-ray diffraction and electron probe microanalysis were used to examine the metallized surface and the seal interface. No continuous interfacial phase occurs. A second phase occurs as pockets at the interface. Glass migration does not occur. It appears that a diffusion zone in the alumina may be responsible for the adhesion.